NQ, HQ, PQ, NTW & HTW Diamond Core Bits: Sizes, Differences and Selection Guide | Chenghui Drilling<\/title>\n <meta name=\"description\" content=\"Complete guide to NQ, HQ, PQ, NTW and HTW diamond core bit sizes. Learn the differences, thin-wall vs standard systems, and how to select the right impregnated diamond bit for your drilling project.\">\n <meta name=\"keywords\" content=\"NQ diamond core bit, HQ core bit, PQ core bit, NTW core bit, HTW core bit, impregnated diamond bit, hot-pressed diamond core bit, wireline coring system\">\n <style>\n \/* ===== \u6587\u7ae0\u4f5c\u7528\u57df\uff0c\u907f\u514d\u5f71\u54cd\u5168\u7ad9 ===== *\/\n .ch-article-diamond-core-bits {\n max-width: 1100px;\n margin: 0 auto;\n padding: 20px;\n font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;\n color: #1e2f4d;\n line-height: 1.75;\n }\n\n \/* \u6807\u9898\u5c42\u7ea7 *\/\n .ch-article-diamond-core-bits h1 {\n font-size: 2.2rem;\n font-weight: 700;\n color: #0b2538;\n line-height: 1.3;\n margin: 0 0 12px 0;\n letter-spacing: -0.02em;\n }\n\n .ch-article-diamond-core-bits .article-meta {\n font-size: 0.9rem;\n color: #6b7f93;\n margin: 0 0 28px 0;\n padding-bottom: 16px;\n border-bottom: 1px solid #e6eef5;\n }\n\n .ch-article-diamond-core-bits h2 {\n font-size: 1.7rem;\n font-weight: 700;\n color: #0b2538;\n margin-top: 44px;\n margin-bottom: 16px;\n border-left: 5px solid #cc5500;\n padding-left: 18px;\n }\n\n .ch-article-diamond-core-bits h3 {\n font-size: 1.25rem;\n font-weight: 600;\n color: #1a4a6a;\n margin-top: 28px;\n margin-bottom: 10px;\n }\n\n .ch-article-diamond-core-bits p {\n font-size: 1.05rem;\n line-height: 1.8;\n color: #1e3347;\n margin-bottom: 16px;\n }\n\n .ch-article-diamond-core-bits ul {\n margin: 12px 0 20px 24px;\n font-size: 1.05rem;\n color: #1e3347;\n }\n\n .ch-article-diamond-core-bits li {\n margin-bottom: 6px;\n }\n\n \/* \u56fe\u7247\u4e0e\u56fe\u6587\u6846 *\/\n .ch-article-diamond-core-bits .article-figure {\n margin: 32px 0;\n text-align: center;\n }\n\n .ch-article-diamond-core-bits .article-figure img {\n max-width: 100%;\n height: auto;\n border-radius: 18px;\n box-shadow: 0 8px 28px rgba(11, 37, 56, 0.12);\n display: block;\n margin: 0 auto;\n }\n\n .ch-article-diamond-core-bits .article-figure figcaption {\n font-size: 0.9rem;\n color: #6b7f93;\n margin-top: 12px;\n line-height: 1.6;\n }\n\n \/* \u8868\u683c *\/\n .ch-article-diamond-core-bits .table-wrap {\n overflow-x: auto;\n margin: 24px 0;\n border-radius: 14px;\n border: 1px solid #e0eaf2;\n }\n\n .ch-article-diamond-core-bits table {\n width: 100%;\n border-collapse: collapse;\n font-size: 1rem;\n background: #ffffff;\n }\n\n .ch-article-diamond-core-bits thead {\n background: #0b2538;\n color: #ffffff;\n }\n\n .ch-article-diamond-core-bits th {\n padding: 14px 18px;\n text-align: left;\n font-weight: 600;\n font-size: 0.95rem;\n white-space: nowrap;\n }\n\n .ch-article-diamond-core-bits td {\n padding: 13px 18px;\n border-bottom: 1px solid #eaf1f7;\n color: #1e3347;\n }\n\n .ch-article-diamond-core-bits tbody tr:last-child td {\n border-bottom: none;\n }\n\n .ch-article-diamond-core-bits tbody tr:nth-child(even) {\n background: #f8fafc;\n }\n\n \/* \u9ad8\u4eae\u6846 *\/\n .ch-article-diamond-core-bits .info-box {\n background: #f8fafc;\n border-radius: 16px;\n padding: 18px 22px;\n margin: 24px 0;\n border-left: 4px solid #cc5500;\n }\n\n .ch-article-diamond-core-bits .info-box p {\n margin: 0;\n font-size: 1rem;\n color: #1e3347;\n }\n\n .ch-article-diamond-core-bits .highlight-box {\n background: linear-gradient(145deg, #eaf3fa, #f6f9fc);\n border: 1px solid #d0e4f0;\n border-radius: 18px;\n padding: 22px 26px;\n margin: 28px 0;\n }\n\n .ch-article-diamond-core-bits .highlight-box p {\n margin: 0;\n font-size: 1.05rem;\n color: #0b2538;\n }\n\n \/* \u8981\u70b9\u7f51\u683c *\/\n .ch-article-diamond-core-bits .key-grid {\n display: grid;\n grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));\n gap: 16px;\n margin: 26px 0;\n }\n\n .ch-article-diamond-core-bits .key-item {\n background: #f8fafc;\n border: 1px solid #e6eef5;\n border-radius: 16px;\n padding: 20px;\n }\n\n .ch-article-diamond-core-bits .key-item .key-icon {\n font-size: 1.6rem;\n display: block;\n margin-bottom: 8px;\n }\n\n .ch-article-diamond-core-bits .key-item .key-title {\n font-weight: 600;\n color: #0b2538;\n margin-bottom: 6px;\n }\n\n .ch-article-diamond-core-bits .key-item .key-desc {\n font-size: 0.92rem;\n color: #4a6a85;\n line-height: 1.6;\n }\n\n \/* \u95ee\u7b54\u5757 *\/\n .ch-article-diamond-core-bits .faq-item {\n border-bottom: 1px solid #e6eef5;\n padding: 18px 0;\n }\n\n .ch-article-diamond-core-bits .faq-item:last-child {\n border-bottom: none;\n }\n\n .ch-article-diamond-core-bits .faq-item .faq-q {\n font-weight: 600;\n color: #0b2538;\n font-size: 1.08rem;\n margin: 0 0 8px 0;\n }\n\n .ch-article-diamond-core-bits .faq-item .faq-a {\n margin: 0;\n font-size: 1rem;\n color: #1e3347;\n }\n\n \/* CTA *\/\n .ch-article-diamond-core-bits .cta-section {\n background: linear-gradient(145deg, #eaf3fa, #f6f9fc);\n border-radius: 24px;\n padding: 36px 40px;\n margin: 44px 0 20px;\n border: 1px solid #d0e4f0;\n text-align: center;\n }\n\n .ch-article-diamond-core-bits .cta-section p {\n max-width: 750px;\n margin-left: auto;\n margin-right: auto;\n }\n\n .ch-article-diamond-core-bits .btn-group {\n display: flex;\n flex-wrap: wrap;\n justify-content: center;\n gap: 16px;\n margin-top: 20px;\n }\n\n .ch-article-diamond-core-bits .btn {\n display: inline-block;\n padding: 14px 36px;\n border-radius: 60px;\n font-weight: 600;\n font-size: 1.05rem;\n text-decoration: none;\n transition: all 0.2s;\n }\n\n .ch-article-diamond-core-bits .btn-primary {\n background: #cc5500;\n color: #fff;\n }\n\n .ch-article-diamond-core-bits .btn-primary:hover {\n background: #b04400;\n }\n\n .ch-article-diamond-core-bits .btn-secondary {\n background: transparent;\n border: 2px solid #2a7a9a;\n color: #2a7a9a;\n }\n\n .ch-article-diamond-core-bits .btn-secondary:hover {\n background: #2a7a9a;\n color: #fff;\n }\n\n \/* \u54cd\u5e94\u5f0f *\/\n @media (max-width: 768px) {\n .ch-article-diamond-core-bits h1 {\n font-size: 1.6rem;\n }\n .ch-article-diamond-core-bits h2 {\n font-size: 1.35rem;\n }\n .ch-article-diamond-core-bits .cta-section {\n padding: 24px 16px;\n }\n .ch-article-diamond-core-bits .key-grid {\n grid-template-columns: 1fr;\n }\n .ch-article-diamond-core-bits th,\n .ch-article-diamond-core-bits td {\n padding: 10px 12px;\n font-size: 0.92rem;\n }\n }\n <\/style>\n<\/head>\n<body>\n\n<article class=\"ch-article-diamond-core-bits\">\n\n \n <header>\n <h1>NQ, HQ, PQ, NTW & HTW Diamond Core Bits: Sizes, Differences and Selection Guide<\/h1>\n <p class=\"article-meta\">Chenghui Drilling Tools \u00b7 Updated October 2026 \u00b7 8 min read<\/p>\n <\/header>\n\n \n <p>Diamond core drilling is widely used in mineral exploration, geological investigation and rock sampling because it allows drillers to recover a continuous cylindrical core from the formation.<\/p>\n\n <p>Among the most commonly encountered sizes are <strong>NQ, HQ, PQ, NTW and HTW<\/strong>. These names are sometimes treated simply as different drill bit sizes, but there is more behind them.<\/p>\n\n <p>Understanding the difference between these systems is important when selecting a diamond core bit, core barrel and drilling accessories for a particular project.<\/p>\n\n \n <figure class=\"article-figure\">\n <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/chpdc.com\/wp-content\/uploads\/2026\/10\/News-on-Hot-pressed-Diamond-Drill-Bits.webp\"\n alt=\"Hot-pressed diamond core bits \u2013 NQ, HQ, PQ, NTW and HTW sizes from Chenghui Drilling\"\n width=\"1100\" height=\"620\">\n <figcaption>Hot-pressed diamond core bits in NQ, HQ, PQ, NTW and HTW configurations \u2014 each matrix and crown is matched to the formation and drilling system.<\/figcaption>\n <\/figure>\n\n \n <h2>What Is an Impregnated Diamond Core Bit?<\/h2>\n\n <p>An impregnated diamond core bit uses synthetic diamond particles distributed throughout a metal matrix in the cutting crown.<\/p>\n\n <p>During drilling, both the diamonds and the surrounding matrix gradually wear. As the matrix is abraded, new diamond particles are exposed and continue cutting the rock. This controlled wear mechanism is what gives an impregnated diamond bit its self-sharpening characteristics.<\/p>\n\n <p>Boart Longyear describes impregnated diamond bits as tools intended primarily for <strong>medium to ultra-hard formations<\/strong>, with the metal-and-diamond matrix gradually wearing to expose new cutting diamonds.<\/p>\n\n <p>This is fundamentally different from a surface-set diamond bit, where the cutting diamonds are concentrated mainly at the working surface.<\/p>\n\n <p>In manufacturing, the diamond-bearing crown is produced through powder-metallurgy processes involving carefully selected metallic powders, synthetic diamonds, pressure and high temperature. In the drilling-tool market, these products are therefore also commonly referred to as <strong>hot-pressed diamond core bits<\/strong>.<\/p>\n\n <div class=\"info-box\">\n <p>The important point is not simply how the crown is manufactured. Actual drilling performance depends on the relationship between matrix characteristics, diamond size and concentration, rock abrasiveness and hardness, crown and waterway design, rotation speed, weight on bit, penetration rate, and flushing conditions.<\/p>\n <\/div>\n\n <p>A good diamond core bit is therefore not necessarily the hardest bit. It is a bit whose matrix wears at the correct rate for the formation being drilled.<\/p>\n\n \n <h2>NQ, HQ and PQ Are Coring Sizes \u2014 Not Rock-Hardness Grades<\/h2>\n\n <p>One misunderstanding we occasionally see is the assumption that NQ, HQ and PQ represent different hardness levels of diamond bits.<\/p>\n\n <p>They do not.<\/p>\n\n <p>They primarily identify different <strong>wireline coring system sizes<\/strong>.<\/p>\n\n <p>Boart Longyear’s published Q-system specifications give the following nominal dimensions for standard NQ, HQ and PQ systems.<\/p>\n\n <div class=\"table-wrap\">\n <table>\n <thead>\n <tr>\n <th>Size<\/th>\n <th>Approx. Core Diameter<\/th>\n <th>Standard Bit OD<\/th>\n <\/tr>\n <\/thead>\n <tbody>\n <tr><td><strong>NQ<\/strong><\/td><td>47.6 mm<\/td><td>75.3 mm<\/td><\/tr>\n <tr><td><strong>HQ<\/strong><\/td><td>63.5 mm<\/td><td>95.6 mm<\/td><\/tr>\n <tr><td><strong>PQ<\/strong><\/td><td>85.0 mm<\/td><td>122.0 mm<\/td><\/tr>\n <\/tbody>\n <\/table>\n <\/div>\n\n <p>These figures are nominal system dimensions. Actual dimensions can vary slightly according to bit gauge, reaming-shell configuration and manufacturer specifications.<\/p>\n\n <h3>NQ<\/h3>\n <p>NQ is one of the most widely used wireline coring sizes.<\/p>\n <p>With a nominal core diameter of approximately <strong>47.6 mm<\/strong> and a standard bit outside diameter of approximately <strong>75.3 mm<\/strong>, it provides a practical balance between core size, drilling equipment requirements and borehole diameter.<\/p>\n <p>For many mineral exploration and geological drilling programs, this balance makes N-size equipment a common choice.<\/p>\n\n <h3>HQ<\/h3>\n <p>HQ increases the nominal core diameter to approximately <strong>63.5 mm<\/strong>, with a standard bit OD of approximately <strong>95.6 mm<\/strong>.<\/p>\n <p>The larger core gives geologists more material for geological logging, structural observation and sampling.<\/p>\n <p>The trade-off is straightforward: a larger hole requires more rock to be removed and generally places greater demands on the drill rig, drill string, flushing system and overall drilling operation.<\/p>\n\n <h3>PQ<\/h3>\n <p>PQ is larger again, producing a nominal core diameter of approximately <strong>85.0 mm<\/strong> with a standard bit OD of approximately <strong>122.0 mm<\/strong>.<\/p>\n <p>PQ may be selected when obtaining a large-volume core sample is particularly important or when project conditions justify the larger drilling diameter.<\/p>\n <p>It should not automatically be considered \u201cbetter\u201d than NQ or HQ. The correct size depends on the geological objective, drilling depth, available equipment and the amount of core required.<\/p>\n\n \n <h2>What Are NTW and HTW Core Bits?<\/h2>\n\n <p>NTW and HTW belong to the <strong>thin-wall wireline coring family<\/strong>.<\/p>\n\n <p>The concept is simple: by reducing the kerf and changing the geometry of the coring system, a larger diameter core can be recovered without increasing the hole diameter by the same proportion.<\/p>\n\n <p>Typical nominal dimensions are approximately:<\/p>\n\n <div class=\"table-wrap\">\n <table>\n <thead>\n <tr>\n <th>Size<\/th>\n <th>Approx. Core Diameter<\/th>\n <th>Approx. Hole Diameter<\/th>\n <\/tr>\n <\/thead>\n <tbody>\n <tr><td><strong>NTW<\/strong><\/td><td>56.0 mm<\/td><td>75.8 mm<\/td><\/tr>\n <tr><td><strong>HTW<\/strong><\/td><td>71.0 mm<\/td><td>96.0 mm<\/td><\/tr>\n <\/tbody>\n <\/table>\n <\/div>\n\n <p>Published thin-wall system specifications list NTW at approximately <strong>56 mm core diameter<\/strong> and HTW at approximately <strong>71 mm<\/strong>.<\/p>\n\n <p>This becomes particularly interesting when compared with standard NQ and HQ.<\/p>\n\n <p>A standard NQ system produces approximately a 47.6 mm core, whereas NTW produces roughly a 56 mm core while remaining in a similar overall hole-size class.<\/p>\n\n <p>Likewise, HQ produces approximately a 63.5 mm core, while HTW can produce a core of roughly 71 mm in a similar H-size borehole range.<\/p>\n\n <div class=\"highlight-box\">\n <p>That is the main reason thin-wall systems are attractive: <strong>more core can be recovered for approximately the same hole diameter.<\/strong><\/p>\n <\/div>\n\n \n <h2>NQ vs NTW: Which One Should Be Used?<\/h2>\n\n <p>The answer depends on the drilling program rather than the drill bit alone.<\/p>\n\n <p>NQ is a conventional and widely established wireline system. It provides a strong balance between equipment availability, hole size and core recovery.<\/p>\n\n <p>NTW is particularly attractive when the drilling program requires a larger core but maintaining an N-size borehole is desirable.<\/p>\n\n <p>The larger NTW core may provide more geological material for examination and sampling.<\/p>\n\n <p>However, thin-wall systems should not be selected simply because the core diameter is larger. Ground conditions, drilling depth, rod configuration, hole deviation, available equipment and the complete core-barrel system all need to be considered.<\/p>\n\n <p>The same principle applies when comparing <strong>HQ with HTW<\/strong>.<\/p>\n\n \n <h2>How Does an Impregnated Diamond Bit Actually Cut Rock?<\/h2>\n\n <p>An impregnated bit works through a controlled relationship between diamond wear and matrix wear.<\/p>\n\n <p>Ideally, the matrix gradually erodes as the exposed diamonds become worn. Worn diamonds are released and fresh cutting points are exposed from deeper inside the crown.<\/p>\n\n <p>Boart Longyear describes the ideal condition as one where the matrix and diamonds wear together at a relatively even rate.<\/p>\n\n <p>Epiroc similarly describes diamond-impregnated core bits as self-sharpening tools: as the matrix wears, new diamonds should become exposed while dull diamonds are released.<\/p>\n\n <p>This explains why matrix selection is so important.<\/p>\n\n <h3>If the matrix wears too slowly<\/h3>\n <p>The diamonds can become polished and lose their ability to cut effectively.<\/p>\n <p>Penetration rate falls even though the crown may still contain plenty of diamond.<\/p>\n\n <h3>If the matrix wears too quickly<\/h3>\n <p>Fresh diamonds can be released before their cutting potential has been fully used.<\/p>\n <p>Penetration may initially appear good, but bit life can decrease significantly.<\/p>\n\n <div class=\"info-box\">\n <p>The objective is therefore <strong>balanced matrix and diamond wear<\/strong>, not maximum matrix hardness.<\/p>\n <\/div>\n\n \n <h2>Why One Diamond Bit Cannot Be Ideal for Every Formation<\/h2>\n\n <p>Rock formations vary greatly.<\/p>\n\n <p>Even within a single borehole, a drill may move from abrasive sandstone into competent limestone, fractured zones, quartz-rich material or much harder crystalline rock.<\/p>\n\n <p>For this reason, professional impregnated diamond-bit manufacturers use multiple matrix formulations and crown designs.<\/p>\n\n <p>Abrasiveness, compressive strength, grain structure and fracture characteristics can all influence how quickly the matrix wears and how effectively fresh diamonds are exposed.<\/p>\n\n <p>Waterways and crown profiles also matter because they influence cooling and the removal of rock cuttings from the bit face.<\/p>\n\n <p>Modern commercial diamond-bit ranges therefore combine different:<\/p>\n\n <ul>\n <li>matrix formulations;<\/li>\n <li>crown heights;<\/li>\n <li>waterway configurations;<\/li>\n <li>diamond specifications; and<\/li>\n <li>gauge designs.<\/li>\n <\/ul>\n\n <p>For example, commercial diamond-bit ranges include standard, tapered, staged and other waterway configurations rather than relying on one universal crown design.<\/p>\n\n \n <h2>Drilling Parameters Matter as Much as the Bit<\/h2>\n\n <p>Even a correctly selected diamond bit can perform poorly if drilling parameters are unsuitable.<\/p>\n\n <p>For impregnated bits, penetration rate, rotation speed, weight on bit and flushing need to work together.<\/p>\n\n <p>If weight on bit is too low, the diamonds may rub instead of cutting efficiently, contributing to polishing.<\/p>\n\n <p>Excessive loading, on the other hand, can accelerate matrix wear and increase mechanical stresses.<\/p>\n\n <p>Boart Longyear notes that excessive or insufficient weight relative to rotational speed can significantly affect polishing, sharpening and bit consumption.<\/p>\n\n <p>Epiroc also emphasizes that the optimum rate of penetration should be maintained by adjusting <strong>WOB and RPM<\/strong>, while sufficient flushing must be maintained across the bit face.<\/p>\n\n <p>This is why evaluating bit performance should involve more than looking at how many metres one bit drilled.<\/p>\n\n <p>A useful evaluation should also consider penetration rate, drilling time, number of trips, core quality and overall cost per metre.<\/p>\n\n \n <h2>Choosing Between NQ, HQ, PQ, NTW and HTW<\/h2>\n\n <p>There is no single size that is correct for every exploration project.<\/p>\n\n <p>A practical selection should begin with a few questions:<\/p>\n\n <div class=\"key-grid\">\n <div class=\"key-item\">\n <span class=\"key-icon\">\ud83d\udccf<\/span>\n <div class=\"key-title\">How much core is required?<\/div>\n <div class=\"key-desc\">A larger core can provide more material for geological logging and laboratory analysis.<\/div>\n <\/div>\n <div class=\"key-item\">\n <span class=\"key-icon\">\u2699\ufe0f<\/span>\n <div class=\"key-title\">What hole diameter can the project support?<\/div>\n <div class=\"key-desc\">Larger coring systems require more material to be removed and generally increase drilling demand.<\/div>\n <\/div>\n <div class=\"key-item\">\n <span class=\"key-icon\">\ud83d\udd27<\/span>\n <div class=\"key-title\">What drilling equipment is available?<\/div>\n <div class=\"key-desc\">Rig torque, rotation capability, pump capacity, rod system and depth capability must all be considered.<\/div>\n <\/div>\n <div class=\"key-item\">\n <span class=\"key-icon\">\ud83e\udea8<\/span>\n <div class=\"key-title\">What are the ground conditions?<\/div>\n <div class=\"key-desc\">Competent formations, broken ground and abrasive formations can require different bit matrices and crown configurations.<\/div>\n <\/div>\n <div class=\"key-item\">\n <span class=\"key-icon\">\ud83d\udc8e<\/span>\n <div class=\"key-title\">Is a larger core required without substantially increasing hole diameter?<\/div>\n <div class=\"key-desc\">In this situation, thin-wall systems such as NTW or HTW may be worth considering.<\/div>\n <\/div>\n <\/div>\n\n \n <h2>Frequently Asked Questions<\/h2>\n\n <div class=\"faq-item\">\n <p class=\"faq-q\">What is the difference between NQ and HQ core bits?<\/p>\n <p class=\"faq-a\">NQ produces a nominal core diameter of approximately 47.6 mm, while HQ produces approximately 63.5 mm. HQ recovers a larger core sample but requires more drilling power and produces a larger borehole.<\/p>\n <\/div>\n\n <div class=\"faq-item\">\n <p class=\"faq-q\">Are NQ, HQ and PQ hardness grades?<\/p>\n <p class=\"faq-a\">No. NQ, HQ and PQ identify wireline coring system sizes, not rock-hardness grades or diamond quality levels. Matrix hardness is a separate specification chosen for the formation.<\/p>\n <\/div>\n\n <div class=\"faq-item\">\n <p class=\"faq-q\">What is the advantage of NTW and HTW thin-wall core bits?<\/p>\n <p class=\"faq-a\">NTW and HTW recover a larger core diameter while staying in a similar overall hole-size class. NTW produces approximately a 56 mm core in an N-size borehole, while HTW produces approximately a 71 mm core in an H-size borehole.<\/p>\n <\/div>\n\n <div class=\"faq-item\">\n <p class=\"faq-q\">How do I choose the right diamond core bit matrix?<\/p>\n <p class=\"faq-a\">Matrix selection depends on rock hardness, abrasiveness and drilling parameters. Hard, competent formations generally require a softer matrix; abrasive formations require a harder, more wear-resistant matrix. The goal is balanced matrix and diamond wear.<\/p>\n <\/div>\n\n <div class=\"faq-item\">\n <p class=\"faq-q\">What information should I provide when ordering a diamond core bit?<\/p>\n <p class=\"faq-a\">Provide the coring system size (NQ, HQ, PQ, NTW or HTW), rock formation type, drilling depth, rig type and operating conditions. This gives the manufacturer a much better basis for recommending the correct configuration.<\/p>\n <\/div>\n\n \n <h2>Final Thoughts<\/h2>\n\n <p>NQ, HQ, PQ, NTW and HTW should not be viewed simply as five different diamond drill-bit models.<\/p>\n\n <p>They represent different coring-system geometries designed around different combinations of <strong>hole diameter and recovered core diameter<\/strong>.<\/p>\n\n <p>At the same time, selecting the correct size is only part of the job.<\/p>\n\n <p>For an impregnated or hot-pressed diamond core bit to perform properly, its matrix, diamond characteristics, crown design and waterways must also match the formation and drilling parameters.<\/p>\n\n <p>For drilling contractors and exploration teams, the best result normally comes from looking at the complete drilling system rather than selecting a bit based only on its diameter or advertised hardness.<\/p>\n\n <p>When ordering a diamond core bit, providing the <strong>coring system size, rock formation, drilling depth and operating conditions<\/strong> gives the manufacturer a much better basis for recommending the correct configuration.<\/p>\n\n \n <section class=\"cta-section\">\n <p style=\"font-size:1.15rem; line-height:1.8; margin-bottom:12px;\">\n <strong>Need help selecting the right diamond core bit?<\/strong><br>\n Send us your coring system size (NQ, HQ, PQ, NTW or HTW), rock formation and drilling conditions. Our team will recommend a suitable matrix, crown and waterway configuration.\n <\/p>\n <p style=\"font-size:0.95rem; color:#4a6a85; margin-bottom:16px;\">\n Chenghui Drilling Tools \u2014 diamond core bits for geological exploration, rock sampling and water-well drilling.\n <\/p>\n <div class=\"btn-group\">\n <a href=\"https:\/\/api.whatsapp.com\/send\/?phone=8618944995320&text=Hello%2C+I+would+like+to+inquire+about+diamond+core+bits.%0A%0A%28From%3A+Website+Article%29&type=phone_number&app_absent=0\"\n target=\"_blank\" rel=\"noopener noreferrer\" class=\"btn btn-primary\">Contact Our Team<\/a>\n <a href=\"https:\/\/drillmfg.com\/products\/pdc-drill-bits\/\" class=\"btn btn-secondary\">View Diamond Core Bits<\/a>\n <\/div>\n <\/section>\n\n \n <div class=\"info-box\" style=\"margin-top:32px;\">\n <p><strong>About Chenghui Drilling Tools<\/strong><br>\n Chenghui Drilling Tools focuses on drilling tools for geological exploration, rock sampling, water-well drilling and other drilling applications. Diamond core bits can be supplied in commonly used coring-system specifications, with configurations selected according to the required size and formation conditions.<\/p>\n <\/div>\n\n<\/article>\n\n<\/body>\n<\/html>","protected":false},"excerpt":{"rendered":"<p>NQ, HQ, PQ, NTW & HTW Diamond Core Bits: Sizes, Differences and Selection Guide | Chenghui Drilling NQ, HQ, PQ, […]<\/p>\n","protected":false},"author":1,"featured_media":1723,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[47,48],"tags":[],"class_list":["post-1721","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-drilling-knowledge","category-product-guides"],"yoast_head":"\n<title>NQ, HQ, PQ, NTW & HTW Diamond Core Bit Guide<\/title>\n<meta name=\"description\" content=\"Compare NQ, HQ, PQ, NTW and HTW diamond core bits, including core diameter, bit size, applications, matrix selection and drilling tips\" \/>\n<meta name=\"robots\" content=\"noindex, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<meta property=\"og:locale\" content=\"tr_TR\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"NQ, HQ, PQ, NTW & HTW Diamond Core Bit Guide\" \/>\n<meta property=\"og:description\" content=\"Compare NQ, HQ, PQ, NTW and HTW diamond core bits, including core diameter, bit size, applications, matrix selection and drilling tips\" \/>\n<meta property=\"og:url\" content=\"https:\/\/chpdc.com\/tr\/nq-hq-pq-ntw-htw-diamond-core-bits\/\" \/>\n<meta property=\"og:site_name\" content=\"Chenghui Drilling Tools\" \/>\n<meta property=\"article:published_time\" content=\"2026-10-05T04:31:43+00:00\" \/>\n<meta property=\"article:modified_time\" content=\"2026-10-06T03:36:53+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/chpdc.com\/wp-content\/uploads\/2026\/10\/News-on-Hot-pressed-Diamond-Drill-Bits01.webp\" \/>\n\t<meta property=\"og:image:width\" content=\"800\" \/>\n\t<meta property=\"og:image:height\" content=\"800\" \/>\n\t<meta property=\"og:image:type\" content=\"image\/webp\" \/>\n<meta name=\"author\" content=\"Jake\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Yazan:\" \/>\n\t<meta name=\"twitter:data1\" content=\"Jake\" \/>\n\t<meta name=\"twitter:label2\" content=\"Tahmini okuma s\u00fcresi\" \/>\n\t<meta name=\"twitter:data2\" content=\"10 dakika\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\\\/\\\/chpdc.com\\\/nq-hq-pq-ntw-htw-diamond-core-bits\\\/#article\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/chpdc.com\\\/nq-hq-pq-ntw-htw-diamond-core-bits\\\/\"},\"author\":{\"name\":\"Jake\",\"@id\":\"https:\\\/\\\/chpdc.com\\\/#\\\/schema\\\/person\\\/6c3ad31880e4c0c0002a0e8aed5ac474\"},\"headline\":\"NQ, HQ, PQ, NTW & HTW Diamond Core Bits: Sizes, Differences and Selection Guide\",\"datePublished\":\"2026-10-05T04:31:43+00:00\",\"dateModified\":\"2026-10-06T03:36:53+00:00\",\"mainEntityOfPage\":{\"@id\":\"https:\\\/\\\/chpdc.com\\\/nq-hq-pq-ntw-htw-diamond-core-bits\\\/\"},\"wordCount\":1988,\"commentCount\":0,\"publisher\":{\"@id\":\"https:\\\/\\\/chpdc.com\\\/#organization\"},\"image\":{\"@id\":\"https:\\\/\\\/chpdc.com\\\/nq-hq-pq-ntw-htw-diamond-core-bits\\\/#primaryimage\"},\"thumbnailUrl\":\"https:\\\/\\\/chpdc.com\\\/wp-content\\\/uploads\\\/2026\\\/10\\\/News-on-Hot-pressed-Diamond-Drill-Bits01.webp\",\"articleSection\":[\"Drilling Knowledge\",\"Product Guides\"],\"inLanguage\":\"tr\",\"potentialAction\":[{\"@type\":\"CommentAction\",\"name\":\"Comment\",\"target\":[\"https:\\\/\\\/chpdc.com\\\/nq-hq-pq-ntw-htw-diamond-core-bits\\\/#respond\"]}]},{\"@type\":\"WebPage\",\"@id\":\"https:\\\/\\\/chpdc.com\\\/nq-hq-pq-ntw-htw-diamond-core-bits\\\/\",\"url\":\"https:\\\/\\\/chpdc.com\\\/nq-hq-pq-ntw-htw-diamond-core-bits\\\/\",\"name\":\"NQ, HQ, PQ, NTW & HTW Diamond Core Bit Guide\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/chpdc.com\\\/#website\"},\"primaryImageOfPage\":{\"@id\":\"https:\\\/\\\/chpdc.com\\\/nq-hq-pq-ntw-htw-diamond-core-bits\\\/#primaryimage\"},\"image\":{\"@id\":\"https:\\\/\\\/chpdc.com\\\/nq-hq-pq-ntw-htw-diamond-core-bits\\\/#primaryimage\"},\"thumbnailUrl\":\"https:\\\/\\\/chpdc.com\\\/wp-content\\\/uploads\\\/2026\\\/10\\\/News-on-Hot-pressed-Diamond-Drill-Bits01.webp\",\"datePublished\":\"2026-10-05T04:31:43+00:00\",\"dateModified\":\"2026-10-06T03:36:53+00:00\",\"description\":\"Compare NQ, HQ, PQ, NTW and HTW diamond core bits, including core diameter, bit size, applications, matrix selection and drilling tips\",\"breadcrumb\":{\"@id\":\"https:\\\/\\\/chpdc.com\\\/nq-hq-pq-ntw-htw-diamond-core-bits\\\/#breadcrumb\"},\"inLanguage\":\"tr\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\\\/\\\/chpdc.com\\\/nq-hq-pq-ntw-htw-diamond-core-bits\\\/\"]}]},{\"@type\":\"ImageObject\",\"inLanguage\":\"tr\",\"@id\":\"https:\\\/\\\/chpdc.com\\\/nq-hq-pq-ntw-htw-diamond-core-bits\\\/#primaryimage\",\"url\":\"https:\\\/\\\/chpdc.com\\\/wp-content\\\/uploads\\\/2026\\\/10\\\/News-on-Hot-pressed-Diamond-Drill-Bits01.webp\",\"contentUrl\":\"https:\\\/\\\/chpdc.com\\\/wp-content\\\/uploads\\\/2026\\\/10\\\/News-on-Hot-pressed-Diamond-Drill-Bits01.webp\",\"width\":800,\"height\":800},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\\\/\\\/chpdc.com\\\/nq-hq-pq-ntw-htw-diamond-core-bits\\\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"\u9996\u9875\",\"item\":\"https:\\\/\\\/chpdc.com\\\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"NQ, HQ, PQ, NTW & HTW Diamond Core Bits: Sizes, Differences and Selection Guide\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\\\/\\\/chpdc.com\\\/#website\",\"url\":\"https:\\\/\\\/chpdc.com\\\/\",\"name\":\"Chenghui Drilling Tools\",\"description\":\"China Manufacturer of PDC Drill Bits, Tricone Bits, DTH Tools & Drilling Equipment\",\"publisher\":{\"@id\":\"https:\\\/\\\/chpdc.com\\\/#organization\"},\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\\\/\\\/chpdc.com\\\/?s={search_term_string}\"},\"query-input\":{\"@type\":\"PropertyValueSpecification\",\"valueRequired\":true,\"valueName\":\"search_term_string\"}}],\"inLanguage\":\"tr\"},{\"@type\":\"Organization\",\"@id\":\"https:\\\/\\\/chpdc.com\\\/#organization\",\"name\":\"Chenghui Drilling (Shenzhen) Technology Co., Ltd.\",\"url\":\"https:\\\/\\\/chpdc.com\\\/\",\"logo\":{\"@type\":\"ImageObject\",\"inLanguage\":\"tr\",\"@id\":\"https:\\\/\\\/chpdc.com\\\/#\\\/schema\\\/logo\\\/image\\\/\",\"url\":\"https:\\\/\\\/chpdc.com\\\/wp-content\\\/uploads\\\/2026\\\/09\\\/CH-drillmfg-LOGO.jpg\",\"contentUrl\":\"https:\\\/\\\/chpdc.com\\\/wp-content\\\/uploads\\\/2026\\\/09\\\/CH-drillmfg-LOGO.jpg\",\"width\":512,\"height\":512,\"caption\":\"Chenghui Drilling (Shenzhen) Technology Co., Ltd.\"},\"image\":{\"@id\":\"https:\\\/\\\/chpdc.com\\\/#\\\/schema\\\/logo\\\/image\\\/\"}},{\"@type\":\"Person\",\"@id\":\"https:\\\/\\\/chpdc.com\\\/#\\\/schema\\\/person\\\/6c3ad31880e4c0c0002a0e8aed5ac474\",\"name\":\"Jake\",\"image\":{\"@type\":\"ImageObject\",\"inLanguage\":\"tr\",\"@id\":\"https:\\\/\\\/chpdc.com\\\/wp-content\\\/litespeed\\\/avatar\\\/789477abd4541f3d1af76c33ec7ae7ed.jpg?ver=1792389980\",\"url\":\"https:\\\/\\\/chpdc.com\\\/wp-content\\\/litespeed\\\/avatar\\\/789477abd4541f3d1af76c33ec7ae7ed.jpg?ver=1792389980\",\"contentUrl\":\"https:\\\/\\\/chpdc.com\\\/wp-content\\\/litespeed\\\/avatar\\\/789477abd4541f3d1af76c33ec7ae7ed.jpg?ver=1792389980\",\"caption\":\"Jake\"},\"sameAs\":[\"https:\\\/\\\/chpdc.com\"],\"url\":\"https:\\\/\\\/chpdc.com\\\/tr\\\/author\\\/admin\\\/\"}]}<\/script>\n","yoast_head_json":{"title":"NQ, HQ, PQ, NTW & HTW Diamond Core Bit Guide","description":"Compare NQ, HQ, PQ, NTW and HTW diamond core bits, including core diameter, bit size, applications, matrix selection and drilling tips","robots":{"index":"noindex","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"og_locale":"tr_TR","og_type":"article","og_title":"NQ, HQ, PQ, NTW & HTW Diamond Core Bit Guide","og_description":"Compare NQ, HQ, PQ, NTW and HTW diamond core bits, including core diameter, bit size, applications, matrix selection and drilling tips","og_url":"https:\/\/chpdc.com\/tr\/nq-hq-pq-ntw-htw-diamond-core-bits\/","og_site_name":"Chenghui Drilling Tools","article_published_time":"2026-10-05T04:31:43+00:00","article_modified_time":"2026-10-06T03:36:53+00:00","og_image":[{"width":800,"height":800,"url":"https:\/\/chpdc.com\/wp-content\/uploads\/2026\/10\/News-on-Hot-pressed-Diamond-Drill-Bits01.webp","type":"image\/webp"}],"author":"Jake","twitter_card":"summary_large_image","twitter_misc":{"Yazan:":"Jake","Tahmini okuma s\u00fcresi":"10 dakika"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"Article","@id":"https:\/\/chpdc.com\/nq-hq-pq-ntw-htw-diamond-core-bits\/#article","isPartOf":{"@id":"https:\/\/chpdc.com\/nq-hq-pq-ntw-htw-diamond-core-bits\/"},"author":{"name":"Jake","@id":"https:\/\/chpdc.com\/#\/schema\/person\/6c3ad31880e4c0c0002a0e8aed5ac474"},"headline":"NQ, HQ, PQ, NTW & HTW Diamond Core Bits: Sizes, Differences and Selection Guide","datePublished":"2026-10-05T04:31:43+00:00","dateModified":"2026-10-06T03:36:53+00:00","mainEntityOfPage":{"@id":"https:\/\/chpdc.com\/nq-hq-pq-ntw-htw-diamond-core-bits\/"},"wordCount":1988,"commentCount":0,"publisher":{"@id":"https:\/\/chpdc.com\/#organization"},"image":{"@id":"https:\/\/chpdc.com\/nq-hq-pq-ntw-htw-diamond-core-bits\/#primaryimage"},"thumbnailUrl":"https:\/\/chpdc.com\/wp-content\/uploads\/2026\/10\/News-on-Hot-pressed-Diamond-Drill-Bits01.webp","articleSection":["Drilling Knowledge","Product Guides"],"inLanguage":"tr","potentialAction":[{"@type":"CommentAction","name":"Comment","target":["https:\/\/chpdc.com\/nq-hq-pq-ntw-htw-diamond-core-bits\/#respond"]}]},{"@type":"WebPage","@id":"https:\/\/chpdc.com\/nq-hq-pq-ntw-htw-diamond-core-bits\/","url":"https:\/\/chpdc.com\/nq-hq-pq-ntw-htw-diamond-core-bits\/","name":"NQ, HQ, PQ, NTW & HTW Diamond Core Bit Guide","isPartOf":{"@id":"https:\/\/chpdc.com\/#website"},"primaryImageOfPage":{"@id":"https:\/\/chpdc.com\/nq-hq-pq-ntw-htw-diamond-core-bits\/#primaryimage"},"image":{"@id":"https:\/\/chpdc.com\/nq-hq-pq-ntw-htw-diamond-core-bits\/#primaryimage"},"thumbnailUrl":"https:\/\/chpdc.com\/wp-content\/uploads\/2026\/10\/News-on-Hot-pressed-Diamond-Drill-Bits01.webp","datePublished":"2026-10-05T04:31:43+00:00","dateModified":"2026-10-06T03:36:53+00:00","description":"Compare NQ, HQ, PQ, NTW and HTW diamond core bits, including core diameter, bit size, applications, matrix selection and drilling tips","breadcrumb":{"@id":"https:\/\/chpdc.com\/nq-hq-pq-ntw-htw-diamond-core-bits\/#breadcrumb"},"inLanguage":"tr","potentialAction":[{"@type":"ReadAction","target":["https:\/\/chpdc.com\/nq-hq-pq-ntw-htw-diamond-core-bits\/"]}]},{"@type":"ImageObject","inLanguage":"tr","@id":"https:\/\/chpdc.com\/nq-hq-pq-ntw-htw-diamond-core-bits\/#primaryimage","url":"https:\/\/chpdc.com\/wp-content\/uploads\/2026\/10\/News-on-Hot-pressed-Diamond-Drill-Bits01.webp","contentUrl":"https:\/\/chpdc.com\/wp-content\/uploads\/2026\/10\/News-on-Hot-pressed-Diamond-Drill-Bits01.webp","width":800,"height":800},{"@type":"BreadcrumbList","@id":"https:\/\/chpdc.com\/nq-hq-pq-ntw-htw-diamond-core-bits\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"\u9996\u9875","item":"https:\/\/chpdc.com\/"},{"@type":"ListItem","position":2,"name":"NQ, HQ, PQ, NTW & HTW Diamond Core Bits: Sizes, Differences and Selection Guide"}]},{"@type":"WebSite","@id":"https:\/\/chpdc.com\/#website","url":"https:\/\/chpdc.com\/","name":"Chenghui Sondaj Aletleri","description":"\u00c7in\u2019de PDC Matkap U\u00e7lar\u0131, Tricone Matkap U\u00e7lar\u0131, DTH Aletleri ve Sondaj Ekipmanlar\u0131 \u00dcreticisi","publisher":{"@id":"https:\/\/chpdc.com\/#organization"},"potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/chpdc.com\/?s={search_term_string}"},"query-input":{"@type":"PropertyValueSpecification","valueRequired":true,"valueName":"search_term_string"}}],"inLanguage":"tr"},{"@type":"Organization","@id":"https:\/\/chpdc.com\/#organization","name":"Chenghui Drilling (Shenzhen) Teknoloji Ltd. \u015eti.","url":"https:\/\/chpdc.com\/","logo":{"@type":"ImageObject","inLanguage":"tr","@id":"https:\/\/chpdc.com\/#\/schema\/logo\/image\/","url":"https:\/\/chpdc.com\/wp-content\/uploads\/2026\/09\/CH-drillmfg-LOGO.jpg","contentUrl":"https:\/\/chpdc.com\/wp-content\/uploads\/2026\/09\/CH-drillmfg-LOGO.jpg","width":512,"height":512,"caption":"Chenghui Drilling (Shenzhen) Technology Co., Ltd."},"image":{"@id":"https:\/\/chpdc.com\/#\/schema\/logo\/image\/"}},{"@type":"Person","@id":"https:\/\/chpdc.com\/#\/schema\/person\/6c3ad31880e4c0c0002a0e8aed5ac474","name":"Jake","image":{"@type":"ImageObject","inLanguage":"tr","@id":"https:\/\/chpdc.com\/wp-content\/litespeed\/avatar\/789477abd4541f3d1af76c33ec7ae7ed.jpg?ver=1792389980","url":"https:\/\/chpdc.com\/wp-content\/litespeed\/avatar\/789477abd4541f3d1af76c33ec7ae7ed.jpg?ver=1792389980","contentUrl":"https:\/\/chpdc.com\/wp-content\/litespeed\/avatar\/789477abd4541f3d1af76c33ec7ae7ed.jpg?ver=1792389980","caption":"Jake"},"sameAs":["https:\/\/chpdc.com"],"url":"https:\/\/chpdc.com\/tr\/author\/admin\/"}]}},"_links":{"self":[{"href":"https:\/\/chpdc.com\/tr\/wp-json\/wp\/v2\/posts\/1721","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/chpdc.com\/tr\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/chpdc.com\/tr\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/chpdc.com\/tr\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/chpdc.com\/tr\/wp-json\/wp\/v2\/comments?post=1721"}],"version-history":[{"count":2,"href":"https:\/\/chpdc.com\/tr\/wp-json\/wp\/v2\/posts\/1721\/revisions"}],"predecessor-version":[{"id":1726,"href":"https:\/\/chpdc.com\/tr\/wp-json\/wp\/v2\/posts\/1721\/revisions\/1726"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/chpdc.com\/tr\/wp-json\/wp\/v2\/media\/1723"}],"wp:attachment":[{"href":"https:\/\/chpdc.com\/tr\/wp-json\/wp\/v2\/media?parent=1721"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/chpdc.com\/tr\/wp-json\/wp\/v2\/categories?post=1721"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/chpdc.com\/tr\/wp-json\/wp\/v2\/tags?post=1721"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}

{"id":1721,"date":"2026-10-05T12:31:43","date_gmt":"2026-10-05T04:31:43","guid":{"rendered":"https:\/\/chpdc.com\/?p=1721"},"modified":"2026-10-06T11:36:53","modified_gmt":"2026-10-06T03:36:53","slug":"nq-hq-pq-ntw-htw-diamond-core-bits","status":"publish","type":"post","link":"https:\/\/chpdc.com\/tr\/nq-hq-pq-ntw-htw-diamond-core-bits\/","title":{"rendered":"NQ, HQ, PQ, NTW & HTW Diamond Core Bits: Sizes, Differences and Selection Guide"},"content":{"rendered":"\n\n\n \n \n NQ, HQ, PQ, NTW & HTW Diamond Core Bits: Sizes, Differences and Selection Guide | Chenghui Drilling<\/title>\n <meta name=\"description\" content=\"Complete guide to NQ, HQ, PQ, NTW and HTW diamond core bit sizes. Learn the differences, thin-wall vs standard systems, and how to select the right impregnated diamond bit for your drilling project.\">\n <meta name=\"keywords\" content=\"NQ diamond core bit, HQ core bit, PQ core bit, NTW core bit, HTW core bit, impregnated diamond bit, hot-pressed diamond core bit, wireline coring system\">\n <style>\n \/* ===== \u6587\u7ae0\u4f5c\u7528\u57df\uff0c\u907f\u514d\u5f71\u54cd\u5168\u7ad9 ===== *\/\n .ch-article-diamond-core-bits {\n max-width: 1100px;\n margin: 0 auto;\n padding: 20px;\n font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;\n color: #1e2f4d;\n line-height: 1.75;\n }\n\n \/* \u6807\u9898\u5c42\u7ea7 *\/\n .ch-article-diamond-core-bits h1 {\n font-size: 2.2rem;\n font-weight: 700;\n color: #0b2538;\n line-height: 1.3;\n margin: 0 0 12px 0;\n letter-spacing: -0.02em;\n }\n\n .ch-article-diamond-core-bits .article-meta {\n font-size: 0.9rem;\n color: #6b7f93;\n margin: 0 0 28px 0;\n padding-bottom: 16px;\n border-bottom: 1px solid #e6eef5;\n }\n\n .ch-article-diamond-core-bits h2 {\n font-size: 1.7rem;\n font-weight: 700;\n color: #0b2538;\n margin-top: 44px;\n margin-bottom: 16px;\n border-left: 5px solid #cc5500;\n padding-left: 18px;\n }\n\n .ch-article-diamond-core-bits h3 {\n font-size: 1.25rem;\n font-weight: 600;\n color: #1a4a6a;\n margin-top: 28px;\n margin-bottom: 10px;\n }\n\n .ch-article-diamond-core-bits p {\n font-size: 1.05rem;\n line-height: 1.8;\n color: #1e3347;\n margin-bottom: 16px;\n }\n\n .ch-article-diamond-core-bits ul {\n margin: 12px 0 20px 24px;\n font-size: 1.05rem;\n color: #1e3347;\n }\n\n .ch-article-diamond-core-bits li {\n margin-bottom: 6px;\n }\n\n \/* \u56fe\u7247\u4e0e\u56fe\u6587\u6846 *\/\n .ch-article-diamond-core-bits .article-figure {\n margin: 32px 0;\n text-align: center;\n }\n\n .ch-article-diamond-core-bits .article-figure img {\n max-width: 100%;\n height: auto;\n border-radius: 18px;\n box-shadow: 0 8px 28px rgba(11, 37, 56, 0.12);\n display: block;\n margin: 0 auto;\n }\n\n .ch-article-diamond-core-bits .article-figure figcaption {\n font-size: 0.9rem;\n color: #6b7f93;\n margin-top: 12px;\n line-height: 1.6;\n }\n\n \/* \u8868\u683c *\/\n .ch-article-diamond-core-bits .table-wrap {\n overflow-x: auto;\n margin: 24px 0;\n border-radius: 14px;\n border: 1px solid #e0eaf2;\n }\n\n .ch-article-diamond-core-bits table {\n width: 100%;\n border-collapse: collapse;\n font-size: 1rem;\n background: #ffffff;\n }\n\n .ch-article-diamond-core-bits thead {\n background: #0b2538;\n color: #ffffff;\n }\n\n .ch-article-diamond-core-bits th {\n padding: 14px 18px;\n text-align: left;\n font-weight: 600;\n font-size: 0.95rem;\n white-space: nowrap;\n }\n\n .ch-article-diamond-core-bits td {\n padding: 13px 18px;\n border-bottom: 1px solid #eaf1f7;\n color: #1e3347;\n }\n\n .ch-article-diamond-core-bits tbody tr:last-child td {\n border-bottom: none;\n }\n\n .ch-article-diamond-core-bits tbody tr:nth-child(even) {\n background: #f8fafc;\n }\n\n \/* \u9ad8\u4eae\u6846 *\/\n .ch-article-diamond-core-bits .info-box {\n background: #f8fafc;\n border-radius: 16px;\n padding: 18px 22px;\n margin: 24px 0;\n border-left: 4px solid #cc5500;\n }\n\n .ch-article-diamond-core-bits .info-box p {\n margin: 0;\n font-size: 1rem;\n color: #1e3347;\n }\n\n .ch-article-diamond-core-bits .highlight-box {\n background: linear-gradient(145deg, #eaf3fa, #f6f9fc);\n border: 1px solid #d0e4f0;\n border-radius: 18px;\n padding: 22px 26px;\n margin: 28px 0;\n }\n\n .ch-article-diamond-core-bits .highlight-box p {\n margin: 0;\n font-size: 1.05rem;\n color: #0b2538;\n }\n\n \/* \u8981\u70b9\u7f51\u683c *\/\n .ch-article-diamond-core-bits .key-grid {\n display: grid;\n grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));\n gap: 16px;\n margin: 26px 0;\n }\n\n .ch-article-diamond-core-bits .key-item {\n background: #f8fafc;\n border: 1px solid #e6eef5;\n border-radius: 16px;\n padding: 20px;\n }\n\n .ch-article-diamond-core-bits .key-item .key-icon {\n font-size: 1.6rem;\n display: block;\n margin-bottom: 8px;\n }\n\n .ch-article-diamond-core-bits .key-item .key-title {\n font-weight: 600;\n color: #0b2538;\n margin-bottom: 6px;\n }\n\n .ch-article-diamond-core-bits .key-item .key-desc {\n font-size: 0.92rem;\n color: #4a6a85;\n line-height: 1.6;\n }\n\n \/* \u95ee\u7b54\u5757 *\/\n .ch-article-diamond-core-bits .faq-item {\n border-bottom: 1px solid #e6eef5;\n padding: 18px 0;\n }\n\n .ch-article-diamond-core-bits .faq-item:last-child {\n border-bottom: none;\n }\n\n .ch-article-diamond-core-bits .faq-item .faq-q {\n font-weight: 600;\n color: #0b2538;\n font-size: 1.08rem;\n margin: 0 0 8px 0;\n }\n\n .ch-article-diamond-core-bits .faq-item .faq-a {\n margin: 0;\n font-size: 1rem;\n color: #1e3347;\n }\n\n \/* CTA *\/\n .ch-article-diamond-core-bits .cta-section {\n background: linear-gradient(145deg, #eaf3fa, #f6f9fc);\n border-radius: 24px;\n padding: 36px 40px;\n margin: 44px 0 20px;\n border: 1px solid #d0e4f0;\n text-align: center;\n }\n\n .ch-article-diamond-core-bits .cta-section p {\n max-width: 750px;\n margin-left: auto;\n margin-right: auto;\n }\n\n .ch-article-diamond-core-bits .btn-group {\n display: flex;\n flex-wrap: wrap;\n justify-content: center;\n gap: 16px;\n margin-top: 20px;\n }\n\n .ch-article-diamond-core-bits .btn {\n display: inline-block;\n padding: 14px 36px;\n border-radius: 60px;\n font-weight: 600;\n font-size: 1.05rem;\n text-decoration: none;\n transition: all 0.2s;\n }\n\n .ch-article-diamond-core-bits .btn-primary {\n background: #cc5500;\n color: #fff;\n }\n\n .ch-article-diamond-core-bits .btn-primary:hover {\n background: #b04400;\n }\n\n .ch-article-diamond-core-bits .btn-secondary {\n background: transparent;\n border: 2px solid #2a7a9a;\n color: #2a7a9a;\n }\n\n .ch-article-diamond-core-bits .btn-secondary:hover {\n background: #2a7a9a;\n color: #fff;\n }\n\n \/* \u54cd\u5e94\u5f0f *\/\n @media (max-width: 768px) {\n .ch-article-diamond-core-bits h1 {\n font-size: 1.6rem;\n }\n .ch-article-diamond-core-bits h2 {\n font-size: 1.35rem;\n }\n .ch-article-diamond-core-bits .cta-section {\n padding: 24px 16px;\n }\n .ch-article-diamond-core-bits .key-grid {\n grid-template-columns: 1fr;\n }\n .ch-article-diamond-core-bits th,\n .ch-article-diamond-core-bits td {\n padding: 10px 12px;\n font-size: 0.92rem;\n }\n }\n <\/style>\n<\/head>\n<body>\n\n<article class=\"ch-article-diamond-core-bits\">\n\n \n <header>\n <h1>NQ, HQ, PQ, NTW & HTW Diamond Core Bits: Sizes, Differences and Selection Guide<\/h1>\n <p class=\"article-meta\">Chenghui Drilling Tools \u00b7 Updated October 2026 \u00b7 8 min read<\/p>\n <\/header>\n\n \n <p>Diamond core drilling is widely used in mineral exploration, geological investigation and rock sampling because it allows drillers to recover a continuous cylindrical core from the formation.<\/p>\n\n <p>Among the most commonly encountered sizes are <strong>NQ, HQ, PQ, NTW and HTW<\/strong>. These names are sometimes treated simply as different drill bit sizes, but there is more behind them.<\/p>\n\n <p>Understanding the difference between these systems is important when selecting a diamond core bit, core barrel and drilling accessories for a particular project.<\/p>\n\n \n <figure class=\"article-figure\">\n <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/chpdc.com\/wp-content\/uploads\/2026\/10\/News-on-Hot-pressed-Diamond-Drill-Bits.webp\"\n alt=\"Hot-pressed diamond core bits \u2013 NQ, HQ, PQ, NTW and HTW sizes from Chenghui Drilling\"\n width=\"1100\" height=\"620\">\n <figcaption>Hot-pressed diamond core bits in NQ, HQ, PQ, NTW and HTW configurations \u2014 each matrix and crown is matched to the formation and drilling system.<\/figcaption>\n <\/figure>\n\n \n <h2>What Is an Impregnated Diamond Core Bit?<\/h2>\n\n <p>An impregnated diamond core bit uses synthetic diamond particles distributed throughout a metal matrix in the cutting crown.<\/p>\n\n <p>During drilling, both the diamonds and the surrounding matrix gradually wear. As the matrix is abraded, new diamond particles are exposed and continue cutting the rock. This controlled wear mechanism is what gives an impregnated diamond bit its self-sharpening characteristics.<\/p>\n\n <p>Boart Longyear describes impregnated diamond bits as tools intended primarily for <strong>medium to ultra-hard formations<\/strong>, with the metal-and-diamond matrix gradually wearing to expose new cutting diamonds.<\/p>\n\n <p>This is fundamentally different from a surface-set diamond bit, where the cutting diamonds are concentrated mainly at the working surface.<\/p>\n\n <p>In manufacturing, the diamond-bearing crown is produced through powder-metallurgy processes involving carefully selected metallic powders, synthetic diamonds, pressure and high temperature. In the drilling-tool market, these products are therefore also commonly referred to as <strong>hot-pressed diamond core bits<\/strong>.<\/p>\n\n <div class=\"info-box\">\n <p>The important point is not simply how the crown is manufactured. Actual drilling performance depends on the relationship between matrix characteristics, diamond size and concentration, rock abrasiveness and hardness, crown and waterway design, rotation speed, weight on bit, penetration rate, and flushing conditions.<\/p>\n <\/div>\n\n <p>A good diamond core bit is therefore not necessarily the hardest bit. It is a bit whose matrix wears at the correct rate for the formation being drilled.<\/p>\n\n \n <h2>NQ, HQ and PQ Are Coring Sizes \u2014 Not Rock-Hardness Grades<\/h2>\n\n <p>One misunderstanding we occasionally see is the assumption that NQ, HQ and PQ represent different hardness levels of diamond bits.<\/p>\n\n <p>They do not.<\/p>\n\n <p>They primarily identify different <strong>wireline coring system sizes<\/strong>.<\/p>\n\n <p>Boart Longyear’s published Q-system specifications give the following nominal dimensions for standard NQ, HQ and PQ systems.<\/p>\n\n <div class=\"table-wrap\">\n <table>\n <thead>\n <tr>\n <th>Size<\/th>\n <th>Approx. Core Diameter<\/th>\n <th>Standard Bit OD<\/th>\n <\/tr>\n <\/thead>\n <tbody>\n <tr><td><strong>NQ<\/strong><\/td><td>47.6 mm<\/td><td>75.3 mm<\/td><\/tr>\n <tr><td><strong>HQ<\/strong><\/td><td>63.5 mm<\/td><td>95.6 mm<\/td><\/tr>\n <tr><td><strong>PQ<\/strong><\/td><td>85.0 mm<\/td><td>122.0 mm<\/td><\/tr>\n <\/tbody>\n <\/table>\n <\/div>\n\n <p>These figures are nominal system dimensions. Actual dimensions can vary slightly according to bit gauge, reaming-shell configuration and manufacturer specifications.<\/p>\n\n <h3>NQ<\/h3>\n <p>NQ is one of the most widely used wireline coring sizes.<\/p>\n <p>With a nominal core diameter of approximately <strong>47.6 mm<\/strong> and a standard bit outside diameter of approximately <strong>75.3 mm<\/strong>, it provides a practical balance between core size, drilling equipment requirements and borehole diameter.<\/p>\n <p>For many mineral exploration and geological drilling programs, this balance makes N-size equipment a common choice.<\/p>\n\n <h3>HQ<\/h3>\n <p>HQ increases the nominal core diameter to approximately <strong>63.5 mm<\/strong>, with a standard bit OD of approximately <strong>95.6 mm<\/strong>.<\/p>\n <p>The larger core gives geologists more material for geological logging, structural observation and sampling.<\/p>\n <p>The trade-off is straightforward: a larger hole requires more rock to be removed and generally places greater demands on the drill rig, drill string, flushing system and overall drilling operation.<\/p>\n\n <h3>PQ<\/h3>\n <p>PQ is larger again, producing a nominal core diameter of approximately <strong>85.0 mm<\/strong> with a standard bit OD of approximately <strong>122.0 mm<\/strong>.<\/p>\n <p>PQ may be selected when obtaining a large-volume core sample is particularly important or when project conditions justify the larger drilling diameter.<\/p>\n <p>It should not automatically be considered \u201cbetter\u201d than NQ or HQ. The correct size depends on the geological objective, drilling depth, available equipment and the amount of core required.<\/p>\n\n \n <h2>What Are NTW and HTW Core Bits?<\/h2>\n\n <p>NTW and HTW belong to the <strong>thin-wall wireline coring family<\/strong>.<\/p>\n\n <p>The concept is simple: by reducing the kerf and changing the geometry of the coring system, a larger diameter core can be recovered without increasing the hole diameter by the same proportion.<\/p>\n\n <p>Typical nominal dimensions are approximately:<\/p>\n\n <div class=\"table-wrap\">\n <table>\n <thead>\n <tr>\n <th>Size<\/th>\n <th>Approx. Core Diameter<\/th>\n <th>Approx. Hole Diameter<\/th>\n <\/tr>\n <\/thead>\n <tbody>\n <tr><td><strong>NTW<\/strong><\/td><td>56.0 mm<\/td><td>75.8 mm<\/td><\/tr>\n <tr><td><strong>HTW<\/strong><\/td><td>71.0 mm<\/td><td>96.0 mm<\/td><\/tr>\n <\/tbody>\n <\/table>\n <\/div>\n\n <p>Published thin-wall system specifications list NTW at approximately <strong>56 mm core diameter<\/strong> and HTW at approximately <strong>71 mm<\/strong>.<\/p>\n\n <p>This becomes particularly interesting when compared with standard NQ and HQ.<\/p>\n\n <p>A standard NQ system produces approximately a 47.6 mm core, whereas NTW produces roughly a 56 mm core while remaining in a similar overall hole-size class.<\/p>\n\n <p>Likewise, HQ produces approximately a 63.5 mm core, while HTW can produce a core of roughly 71 mm in a similar H-size borehole range.<\/p>\n\n <div class=\"highlight-box\">\n <p>That is the main reason thin-wall systems are attractive: <strong>more core can be recovered for approximately the same hole diameter.<\/strong><\/p>\n <\/div>\n\n \n <h2>NQ vs NTW: Which One Should Be Used?<\/h2>\n\n <p>The answer depends on the drilling program rather than the drill bit alone.<\/p>\n\n <p>NQ is a conventional and widely established wireline system. It provides a strong balance between equipment availability, hole size and core recovery.<\/p>\n\n <p>NTW is particularly attractive when the drilling program requires a larger core but maintaining an N-size borehole is desirable.<\/p>\n\n <p>The larger NTW core may provide more geological material for examination and sampling.<\/p>\n\n <p>However, thin-wall systems should not be selected simply because the core diameter is larger. Ground conditions, drilling depth, rod configuration, hole deviation, available equipment and the complete core-barrel system all need to be considered.<\/p>\n\n <p>The same principle applies when comparing <strong>HQ with HTW<\/strong>.<\/p>\n\n \n <h2>How Does an Impregnated Diamond Bit Actually Cut Rock?<\/h2>\n\n <p>An impregnated bit works through a controlled relationship between diamond wear and matrix wear.<\/p>\n\n <p>Ideally, the matrix gradually erodes as the exposed diamonds become worn. Worn diamonds are released and fresh cutting points are exposed from deeper inside the crown.<\/p>\n\n <p>Boart Longyear describes the ideal condition as one where the matrix and diamonds wear together at a relatively even rate.<\/p>\n\n <p>Epiroc similarly describes diamond-impregnated core bits as self-sharpening tools: as the matrix wears, new diamonds should become exposed while dull diamonds are released.<\/p>\n\n <p>This explains why matrix selection is so important.<\/p>\n\n <h3>If the matrix wears too slowly<\/h3>\n <p>The diamonds can become polished and lose their ability to cut effectively.<\/p>\n <p>Penetration rate falls even though the crown may still contain plenty of diamond.<\/p>\n\n <h3>If the matrix wears too quickly<\/h3>\n <p>Fresh diamonds can be released before their cutting potential has been fully used.<\/p>\n <p>Penetration may initially appear good, but bit life can decrease significantly.<\/p>\n\n <div class=\"info-box\">\n <p>The objective is therefore <strong>balanced matrix and diamond wear<\/strong>, not maximum matrix hardness.<\/p>\n <\/div>\n\n \n <h2>Why One Diamond Bit Cannot Be Ideal for Every Formation<\/h2>\n\n <p>Rock formations vary greatly.<\/p>\n\n <p>Even within a single borehole, a drill may move from abrasive sandstone into competent limestone, fractured zones, quartz-rich material or much harder crystalline rock.<\/p>\n\n <p>For this reason, professional impregnated diamond-bit manufacturers use multiple matrix formulations and crown designs.<\/p>\n\n <p>Abrasiveness, compressive strength, grain structure and fracture characteristics can all influence how quickly the matrix wears and how effectively fresh diamonds are exposed.<\/p>\n\n <p>Waterways and crown profiles also matter because they influence cooling and the removal of rock cuttings from the bit face.<\/p>\n\n <p>Modern commercial diamond-bit ranges therefore combine different:<\/p>\n\n <ul>\n <li>matrix formulations;<\/li>\n <li>crown heights;<\/li>\n <li>waterway configurations;<\/li>\n <li>diamond specifications; and<\/li>\n <li>gauge designs.<\/li>\n <\/ul>\n\n <p>For example, commercial diamond-bit ranges include standard, tapered, staged and other waterway configurations rather than relying on one universal crown design.<\/p>\n\n \n <h2>Drilling Parameters Matter as Much as the Bit<\/h2>\n\n <p>Even a correctly selected diamond bit can perform poorly if drilling parameters are unsuitable.<\/p>\n\n <p>For impregnated bits, penetration rate, rotation speed, weight on bit and flushing need to work together.<\/p>\n\n <p>If weight on bit is too low, the diamonds may rub instead of cutting efficiently, contributing to polishing.<\/p>\n\n <p>Excessive loading, on the other hand, can accelerate matrix wear and increase mechanical stresses.<\/p>\n\n <p>Boart Longyear notes that excessive or insufficient weight relative to rotational speed can significantly affect polishing, sharpening and bit consumption.<\/p>\n\n <p>Epiroc also emphasizes that the optimum rate of penetration should be maintained by adjusting <strong>WOB and RPM<\/strong>, while sufficient flushing must be maintained across the bit face.<\/p>\n\n <p>This is why evaluating bit performance should involve more than looking at how many metres one bit drilled.<\/p>\n\n <p>A useful evaluation should also consider penetration rate, drilling time, number of trips, core quality and overall cost per metre.<\/p>\n\n \n <h2>Choosing Between NQ, HQ, PQ, NTW and HTW<\/h2>\n\n <p>There is no single size that is correct for every exploration project.<\/p>\n\n <p>A practical selection should begin with a few questions:<\/p>\n\n <div class=\"key-grid\">\n <div class=\"key-item\">\n <span class=\"key-icon\">\ud83d\udccf<\/span>\n <div class=\"key-title\">How much core is required?<\/div>\n <div class=\"key-desc\">A larger core can provide more material for geological logging and laboratory analysis.<\/div>\n <\/div>\n <div class=\"key-item\">\n <span class=\"key-icon\">\u2699\ufe0f<\/span>\n <div class=\"key-title\">What hole diameter can the project support?<\/div>\n <div class=\"key-desc\">Larger coring systems require more material to be removed and generally increase drilling demand.<\/div>\n <\/div>\n <div class=\"key-item\">\n <span class=\"key-icon\">\ud83d\udd27<\/span>\n <div class=\"key-title\">What drilling equipment is available?<\/div>\n <div class=\"key-desc\">Rig torque, rotation capability, pump capacity, rod system and depth capability must all be considered.<\/div>\n <\/div>\n <div class=\"key-item\">\n <span class=\"key-icon\">\ud83e\udea8<\/span>\n <div class=\"key-title\">What are the ground conditions?<\/div>\n <div class=\"key-desc\">Competent formations, broken ground and abrasive formations can require different bit matrices and crown configurations.<\/div>\n <\/div>\n <div class=\"key-item\">\n <span class=\"key-icon\">\ud83d\udc8e<\/span>\n <div class=\"key-title\">Is a larger core required without substantially increasing hole diameter?<\/div>\n <div class=\"key-desc\">In this situation, thin-wall systems such as NTW or HTW may be worth considering.<\/div>\n <\/div>\n <\/div>\n\n \n <h2>Frequently Asked Questions<\/h2>\n\n <div class=\"faq-item\">\n <p class=\"faq-q\">What is the difference between NQ and HQ core bits?<\/p>\n <p class=\"faq-a\">NQ produces a nominal core diameter of approximately 47.6 mm, while HQ produces approximately 63.5 mm. HQ recovers a larger core sample but requires more drilling power and produces a larger borehole.<\/p>\n <\/div>\n\n <div class=\"faq-item\">\n <p class=\"faq-q\">Are NQ, HQ and PQ hardness grades?<\/p>\n <p class=\"faq-a\">No. NQ, HQ and PQ identify wireline coring system sizes, not rock-hardness grades or diamond quality levels. Matrix hardness is a separate specification chosen for the formation.<\/p>\n <\/div>\n\n <div class=\"faq-item\">\n <p class=\"faq-q\">What is the advantage of NTW and HTW thin-wall core bits?<\/p>\n <p class=\"faq-a\">NTW and HTW recover a larger core diameter while staying in a similar overall hole-size class. NTW produces approximately a 56 mm core in an N-size borehole, while HTW produces approximately a 71 mm core in an H-size borehole.<\/p>\n <\/div>\n\n <div class=\"faq-item\">\n <p class=\"faq-q\">How do I choose the right diamond core bit matrix?<\/p>\n <p class=\"faq-a\">Matrix selection depends on rock hardness, abrasiveness and drilling parameters. Hard, competent formations generally require a softer matrix; abrasive formations require a harder, more wear-resistant matrix. The goal is balanced matrix and diamond wear.<\/p>\n <\/div>\n\n <div class=\"faq-item\">\n <p class=\"faq-q\">What information should I provide when ordering a diamond core bit?<\/p>\n <p class=\"faq-a\">Provide the coring system size (NQ, HQ, PQ, NTW or HTW), rock formation type, drilling depth, rig type and operating conditions. This gives the manufacturer a much better basis for recommending the correct configuration.<\/p>\n <\/div>\n\n \n <h2>Final Thoughts<\/h2>\n\n <p>NQ, HQ, PQ, NTW and HTW should not be viewed simply as five different diamond drill-bit models.<\/p>\n\n <p>They represent different coring-system geometries designed around different combinations of <strong>hole diameter and recovered core diameter<\/strong>.<\/p>\n\n <p>At the same time, selecting the correct size is only part of the job.<\/p>\n\n <p>For an impregnated or hot-pressed diamond core bit to perform properly, its matrix, diamond characteristics, crown design and waterways must also match the formation and drilling parameters.<\/p>\n\n <p>For drilling contractors and exploration teams, the best result normally comes from looking at the complete drilling system rather than selecting a bit based only on its diameter or advertised hardness.<\/p>\n\n <p>When ordering a diamond core bit, providing the <strong>coring system size, rock formation, drilling depth and operating conditions<\/strong> gives the manufacturer a much better basis for recommending the correct configuration.<\/p>\n\n \n <section class=\"cta-section\">\n <p style=\"font-size:1.15rem; line-height:1.8; margin-bottom:12px;\">\n <strong>Need help selecting the right diamond core bit?<\/strong><br>\n Send us your coring system size (NQ, HQ, PQ, NTW or HTW), rock formation and drilling conditions. Our team will recommend a suitable matrix, crown and waterway configuration.\n <\/p>\n <p style=\"font-size:0.95rem; color:#4a6a85; margin-bottom:16px;\">\n Chenghui Drilling Tools \u2014 diamond core bits for geological exploration, rock sampling and water-well drilling.\n <\/p>\n <div class=\"btn-group\">\n <a href=\"https:\/\/api.whatsapp.com\/send\/?phone=8618944995320&text=Hello%2C+I+would+like+to+inquire+about+diamond+core+bits.%0A%0A%28From%3A+Website+Article%29&type=phone_number&app_absent=0\"\n target=\"_blank\" rel=\"noopener noreferrer\" class=\"btn btn-primary\">Contact Our Team<\/a>\n <a href=\"https:\/\/drillmfg.com\/products\/pdc-drill-bits\/\" class=\"btn btn-secondary\">View Diamond Core Bits<\/a>\n <\/div>\n <\/section>\n\n \n <div class=\"info-box\" style=\"margin-top:32px;\">\n <p><strong>About Chenghui Drilling Tools<\/strong><br>\n Chenghui Drilling Tools focuses on drilling tools for geological exploration, rock sampling, water-well drilling and other drilling applications. Diamond core bits can be supplied in commonly used coring-system specifications, with configurations selected according to the required size and formation conditions.<\/p>\n <\/div>\n\n<\/article>\n\n<\/body>\n<\/html>","protected":false},"excerpt":{"rendered":"<p>NQ, HQ, PQ, NTW & HTW Diamond Core Bits: Sizes, Differences and Selection Guide | Chenghui Drilling NQ, HQ, PQ, […]<\/p>\n","protected":false},"author":1,"featured_media":1723,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[47,48],"tags":[],"class_list":["post-1721","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-drilling-knowledge","category-product-guides"],"yoast_head":"\n<title>NQ, HQ, PQ, NTW & HTW Diamond Core Bit Guide<\/title>\n<meta name=\"description\" content=\"Compare NQ, HQ, PQ, NTW and HTW diamond core bits, including core diameter, bit size, applications, matrix selection and drilling tips\" \/>\n<meta name=\"robots\" content=\"noindex, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<meta property=\"og:locale\" content=\"tr_TR\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"NQ, HQ, PQ, NTW & HTW Diamond Core Bit Guide\" \/>\n<meta property=\"og:description\" content=\"Compare NQ, HQ, PQ, NTW and HTW diamond core bits, including core diameter, bit size, applications, matrix selection and drilling tips\" \/>\n<meta property=\"og:url\" content=\"https:\/\/chpdc.com\/tr\/nq-hq-pq-ntw-htw-diamond-core-bits\/\" \/>\n<meta property=\"og:site_name\" content=\"Chenghui Drilling Tools\" \/>\n<meta property=\"article:published_time\" content=\"2026-10-05T04:31:43+00:00\" \/>\n<meta property=\"article:modified_time\" content=\"2026-10-06T03:36:53+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/chpdc.com\/wp-content\/uploads\/2026\/10\/News-on-Hot-pressed-Diamond-Drill-Bits01.webp\" \/>\n\t<meta property=\"og:image:width\" content=\"800\" \/>\n\t<meta property=\"og:image:height\" content=\"800\" \/>\n\t<meta property=\"og:image:type\" content=\"image\/webp\" \/>\n<meta name=\"author\" content=\"Jake\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Yazan:\" \/>\n\t<meta name=\"twitter:data1\" content=\"Jake\" \/>\n\t<meta name=\"twitter:label2\" content=\"Tahmini okuma s\u00fcresi\" \/>\n\t<meta name=\"twitter:data2\" content=\"10 dakika\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\\\/\\\/chpdc.com\\\/nq-hq-pq-ntw-htw-diamond-core-bits\\\/#article\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/chpdc.com\\\/nq-hq-pq-ntw-htw-diamond-core-bits\\\/\"},\"author\":{\"name\":\"Jake\",\"@id\":\"https:\\\/\\\/chpdc.com\\\/#\\\/schema\\\/person\\\/6c3ad31880e4c0c0002a0e8aed5ac474\"},\"headline\":\"NQ, HQ, PQ, NTW & HTW Diamond Core Bits: Sizes, Differences and Selection Guide\",\"datePublished\":\"2026-10-05T04:31:43+00:00\",\"dateModified\":\"2026-10-06T03:36:53+00:00\",\"mainEntityOfPage\":{\"@id\":\"https:\\\/\\\/chpdc.com\\\/nq-hq-pq-ntw-htw-diamond-core-bits\\\/\"},\"wordCount\":1988,\"commentCount\":0,\"publisher\":{\"@id\":\"https:\\\/\\\/chpdc.com\\\/#organization\"},\"image\":{\"@id\":\"https:\\\/\\\/chpdc.com\\\/nq-hq-pq-ntw-htw-diamond-core-bits\\\/#primaryimage\"},\"thumbnailUrl\":\"https:\\\/\\\/chpdc.com\\\/wp-content\\\/uploads\\\/2026\\\/10\\\/News-on-Hot-pressed-Diamond-Drill-Bits01.webp\",\"articleSection\":[\"Drilling Knowledge\",\"Product Guides\"],\"inLanguage\":\"tr\",\"potentialAction\":[{\"@type\":\"CommentAction\",\"name\":\"Comment\",\"target\":[\"https:\\\/\\\/chpdc.com\\\/nq-hq-pq-ntw-htw-diamond-core-bits\\\/#respond\"]}]},{\"@type\":\"WebPage\",\"@id\":\"https:\\\/\\\/chpdc.com\\\/nq-hq-pq-ntw-htw-diamond-core-bits\\\/\",\"url\":\"https:\\\/\\\/chpdc.com\\\/nq-hq-pq-ntw-htw-diamond-core-bits\\\/\",\"name\":\"NQ, HQ, PQ, NTW & HTW Diamond Core Bit Guide\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/chpdc.com\\\/#website\"},\"primaryImageOfPage\":{\"@id\":\"https:\\\/\\\/chpdc.com\\\/nq-hq-pq-ntw-htw-diamond-core-bits\\\/#primaryimage\"},\"image\":{\"@id\":\"https:\\\/\\\/chpdc.com\\\/nq-hq-pq-ntw-htw-diamond-core-bits\\\/#primaryimage\"},\"thumbnailUrl\":\"https:\\\/\\\/chpdc.com\\\/wp-content\\\/uploads\\\/2026\\\/10\\\/News-on-Hot-pressed-Diamond-Drill-Bits01.webp\",\"datePublished\":\"2026-10-05T04:31:43+00:00\",\"dateModified\":\"2026-10-06T03:36:53+00:00\",\"description\":\"Compare NQ, HQ, PQ, NTW and HTW diamond core bits, including core diameter, bit size, applications, matrix selection and drilling tips\",\"breadcrumb\":{\"@id\":\"https:\\\/\\\/chpdc.com\\\/nq-hq-pq-ntw-htw-diamond-core-bits\\\/#breadcrumb\"},\"inLanguage\":\"tr\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\\\/\\\/chpdc.com\\\/nq-hq-pq-ntw-htw-diamond-core-bits\\\/\"]}]},{\"@type\":\"ImageObject\",\"inLanguage\":\"tr\",\"@id\":\"https:\\\/\\\/chpdc.com\\\/nq-hq-pq-ntw-htw-diamond-core-bits\\\/#primaryimage\",\"url\":\"https:\\\/\\\/chpdc.com\\\/wp-content\\\/uploads\\\/2026\\\/10\\\/News-on-Hot-pressed-Diamond-Drill-Bits01.webp\",\"contentUrl\":\"https:\\\/\\\/chpdc.com\\\/wp-content\\\/uploads\\\/2026\\\/10\\\/News-on-Hot-pressed-Diamond-Drill-Bits01.webp\",\"width\":800,\"height\":800},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\\\/\\\/chpdc.com\\\/nq-hq-pq-ntw-htw-diamond-core-bits\\\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"\u9996\u9875\",\"item\":\"https:\\\/\\\/chpdc.com\\\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"NQ, HQ, PQ, NTW & HTW Diamond Core Bits: Sizes, Differences and Selection Guide\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\\\/\\\/chpdc.com\\\/#website\",\"url\":\"https:\\\/\\\/chpdc.com\\\/\",\"name\":\"Chenghui Drilling Tools\",\"description\":\"China Manufacturer of PDC Drill Bits, Tricone Bits, DTH Tools & Drilling Equipment\",\"publisher\":{\"@id\":\"https:\\\/\\\/chpdc.com\\\/#organization\"},\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\\\/\\\/chpdc.com\\\/?s={search_term_string}\"},\"query-input\":{\"@type\":\"PropertyValueSpecification\",\"valueRequired\":true,\"valueName\":\"search_term_string\"}}],\"inLanguage\":\"tr\"},{\"@type\":\"Organization\",\"@id\":\"https:\\\/\\\/chpdc.com\\\/#organization\",\"name\":\"Chenghui Drilling (Shenzhen) Technology Co., Ltd.\",\"url\":\"https:\\\/\\\/chpdc.com\\\/\",\"logo\":{\"@type\":\"ImageObject\",\"inLanguage\":\"tr\",\"@id\":\"https:\\\/\\\/chpdc.com\\\/#\\\/schema\\\/logo\\\/image\\\/\",\"url\":\"https:\\\/\\\/chpdc.com\\\/wp-content\\\/uploads\\\/2026\\\/09\\\/CH-drillmfg-LOGO.jpg\",\"contentUrl\":\"https:\\\/\\\/chpdc.com\\\/wp-content\\\/uploads\\\/2026\\\/09\\\/CH-drillmfg-LOGO.jpg\",\"width\":512,\"height\":512,\"caption\":\"Chenghui Drilling (Shenzhen) Technology Co., Ltd.\"},\"image\":{\"@id\":\"https:\\\/\\\/chpdc.com\\\/#\\\/schema\\\/logo\\\/image\\\/\"}},{\"@type\":\"Person\",\"@id\":\"https:\\\/\\\/chpdc.com\\\/#\\\/schema\\\/person\\\/6c3ad31880e4c0c0002a0e8aed5ac474\",\"name\":\"Jake\",\"image\":{\"@type\":\"ImageObject\",\"inLanguage\":\"tr\",\"@id\":\"https:\\\/\\\/chpdc.com\\\/wp-content\\\/litespeed\\\/avatar\\\/789477abd4541f3d1af76c33ec7ae7ed.jpg?ver=1792389980\",\"url\":\"https:\\\/\\\/chpdc.com\\\/wp-content\\\/litespeed\\\/avatar\\\/789477abd4541f3d1af76c33ec7ae7ed.jpg?ver=1792389980\",\"contentUrl\":\"https:\\\/\\\/chpdc.com\\\/wp-content\\\/litespeed\\\/avatar\\\/789477abd4541f3d1af76c33ec7ae7ed.jpg?ver=1792389980\",\"caption\":\"Jake\"},\"sameAs\":[\"https:\\\/\\\/chpdc.com\"],\"url\":\"https:\\\/\\\/chpdc.com\\\/tr\\\/author\\\/admin\\\/\"}]}<\/script>\n","yoast_head_json":{"title":"NQ, HQ, PQ, NTW & HTW Diamond Core Bit Guide","description":"Compare NQ, HQ, PQ, NTW and HTW diamond core bits, including core diameter, bit size, applications, matrix selection and drilling tips","robots":{"index":"noindex","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"og_locale":"tr_TR","og_type":"article","og_title":"NQ, HQ, PQ, NTW & HTW Diamond Core Bit Guide","og_description":"Compare NQ, HQ, PQ, NTW and HTW diamond core bits, including core diameter, bit size, applications, matrix selection and drilling tips","og_url":"https:\/\/chpdc.com\/tr\/nq-hq-pq-ntw-htw-diamond-core-bits\/","og_site_name":"Chenghui Drilling Tools","article_published_time":"2026-10-05T04:31:43+00:00","article_modified_time":"2026-10-06T03:36:53+00:00","og_image":[{"width":800,"height":800,"url":"https:\/\/chpdc.com\/wp-content\/uploads\/2026\/10\/News-on-Hot-pressed-Diamond-Drill-Bits01.webp","type":"image\/webp"}],"author":"Jake","twitter_card":"summary_large_image","twitter_misc":{"Yazan:":"Jake","Tahmini okuma s\u00fcresi":"10 dakika"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"Article","@id":"https:\/\/chpdc.com\/nq-hq-pq-ntw-htw-diamond-core-bits\/#article","isPartOf":{"@id":"https:\/\/chpdc.com\/nq-hq-pq-ntw-htw-diamond-core-bits\/"},"author":{"name":"Jake","@id":"https:\/\/chpdc.com\/#\/schema\/person\/6c3ad31880e4c0c0002a0e8aed5ac474"},"headline":"NQ, HQ, PQ, NTW & HTW Diamond Core Bits: Sizes, Differences and Selection Guide","datePublished":"2026-10-05T04:31:43+00:00","dateModified":"2026-10-06T03:36:53+00:00","mainEntityOfPage":{"@id":"https:\/\/chpdc.com\/nq-hq-pq-ntw-htw-diamond-core-bits\/"},"wordCount":1988,"commentCount":0,"publisher":{"@id":"https:\/\/chpdc.com\/#organization"},"image":{"@id":"https:\/\/chpdc.com\/nq-hq-pq-ntw-htw-diamond-core-bits\/#primaryimage"},"thumbnailUrl":"https:\/\/chpdc.com\/wp-content\/uploads\/2026\/10\/News-on-Hot-pressed-Diamond-Drill-Bits01.webp","articleSection":["Drilling Knowledge","Product Guides"],"inLanguage":"tr","potentialAction":[{"@type":"CommentAction","name":"Comment","target":["https:\/\/chpdc.com\/nq-hq-pq-ntw-htw-diamond-core-bits\/#respond"]}]},{"@type":"WebPage","@id":"https:\/\/chpdc.com\/nq-hq-pq-ntw-htw-diamond-core-bits\/","url":"https:\/\/chpdc.com\/nq-hq-pq-ntw-htw-diamond-core-bits\/","name":"NQ, HQ, PQ, NTW & HTW Diamond Core Bit Guide","isPartOf":{"@id":"https:\/\/chpdc.com\/#website"},"primaryImageOfPage":{"@id":"https:\/\/chpdc.com\/nq-hq-pq-ntw-htw-diamond-core-bits\/#primaryimage"},"image":{"@id":"https:\/\/chpdc.com\/nq-hq-pq-ntw-htw-diamond-core-bits\/#primaryimage"},"thumbnailUrl":"https:\/\/chpdc.com\/wp-content\/uploads\/2026\/10\/News-on-Hot-pressed-Diamond-Drill-Bits01.webp","datePublished":"2026-10-05T04:31:43+00:00","dateModified":"2026-10-06T03:36:53+00:00","description":"Compare NQ, HQ, PQ, NTW and HTW diamond core bits, including core diameter, bit size, applications, matrix selection and drilling tips","breadcrumb":{"@id":"https:\/\/chpdc.com\/nq-hq-pq-ntw-htw-diamond-core-bits\/#breadcrumb"},"inLanguage":"tr","potentialAction":[{"@type":"ReadAction","target":["https:\/\/chpdc.com\/nq-hq-pq-ntw-htw-diamond-core-bits\/"]}]},{"@type":"ImageObject","inLanguage":"tr","@id":"https:\/\/chpdc.com\/nq-hq-pq-ntw-htw-diamond-core-bits\/#primaryimage","url":"https:\/\/chpdc.com\/wp-content\/uploads\/2026\/10\/News-on-Hot-pressed-Diamond-Drill-Bits01.webp","contentUrl":"https:\/\/chpdc.com\/wp-content\/uploads\/2026\/10\/News-on-Hot-pressed-Diamond-Drill-Bits01.webp","width":800,"height":800},{"@type":"BreadcrumbList","@id":"https:\/\/chpdc.com\/nq-hq-pq-ntw-htw-diamond-core-bits\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"\u9996\u9875","item":"https:\/\/chpdc.com\/"},{"@type":"ListItem","position":2,"name":"NQ, HQ, PQ, NTW & HTW Diamond Core Bits: Sizes, Differences and Selection Guide"}]},{"@type":"WebSite","@id":"https:\/\/chpdc.com\/#website","url":"https:\/\/chpdc.com\/","name":"Chenghui Sondaj Aletleri","description":"\u00c7in\u2019de PDC Matkap U\u00e7lar\u0131, Tricone Matkap U\u00e7lar\u0131, DTH Aletleri ve Sondaj Ekipmanlar\u0131 \u00dcreticisi","publisher":{"@id":"https:\/\/chpdc.com\/#organization"},"potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/chpdc.com\/?s={search_term_string}"},"query-input":{"@type":"PropertyValueSpecification","valueRequired":true,"valueName":"search_term_string"}}],"inLanguage":"tr"},{"@type":"Organization","@id":"https:\/\/chpdc.com\/#organization","name":"Chenghui Drilling (Shenzhen) Teknoloji Ltd. \u015eti.","url":"https:\/\/chpdc.com\/","logo":{"@type":"ImageObject","inLanguage":"tr","@id":"https:\/\/chpdc.com\/#\/schema\/logo\/image\/","url":"https:\/\/chpdc.com\/wp-content\/uploads\/2026\/09\/CH-drillmfg-LOGO.jpg","contentUrl":"https:\/\/chpdc.com\/wp-content\/uploads\/2026\/09\/CH-drillmfg-LOGO.jpg","width":512,"height":512,"caption":"Chenghui Drilling (Shenzhen) Technology Co., Ltd."},"image":{"@id":"https:\/\/chpdc.com\/#\/schema\/logo\/image\/"}},{"@type":"Person","@id":"https:\/\/chpdc.com\/#\/schema\/person\/6c3ad31880e4c0c0002a0e8aed5ac474","name":"Jake","image":{"@type":"ImageObject","inLanguage":"tr","@id":"https:\/\/chpdc.com\/wp-content\/litespeed\/avatar\/789477abd4541f3d1af76c33ec7ae7ed.jpg?ver=1792389980","url":"https:\/\/chpdc.com\/wp-content\/litespeed\/avatar\/789477abd4541f3d1af76c33ec7ae7ed.jpg?ver=1792389980","contentUrl":"https:\/\/chpdc.com\/wp-content\/litespeed\/avatar\/789477abd4541f3d1af76c33ec7ae7ed.jpg?ver=1792389980","caption":"Jake"},"sameAs":["https:\/\/chpdc.com"],"url":"https:\/\/chpdc.com\/tr\/author\/admin\/"}]}},"_links":{"self":[{"href":"https:\/\/chpdc.com\/tr\/wp-json\/wp\/v2\/posts\/1721","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/chpdc.com\/tr\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/chpdc.com\/tr\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/chpdc.com\/tr\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/chpdc.com\/tr\/wp-json\/wp\/v2\/comments?post=1721"}],"version-history":[{"count":2,"href":"https:\/\/chpdc.com\/tr\/wp-json\/wp\/v2\/posts\/1721\/revisions"}],"predecessor-version":[{"id":1726,"href":"https:\/\/chpdc.com\/tr\/wp-json\/wp\/v2\/posts\/1721\/revisions\/1726"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/chpdc.com\/tr\/wp-json\/wp\/v2\/media\/1723"}],"wp:attachment":[{"href":"https:\/\/chpdc.com\/tr\/wp-json\/wp\/v2\/media?parent=1721"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/chpdc.com\/tr\/wp-json\/wp\/v2\/categories?post=1721"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/chpdc.com\/tr\/wp-json\/wp\/v2\/tags?post=1721"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}