Thread Button Bits: The Complete Guide to Rock Drilling Tool Selection and Sourcing

Everything you need to know about choosing the right thread button bit for mining, tunneling, and quarrying — from thread types and face designs to supplier selection.

When it comes to hard rock drilling in mining, tunneling, and quarrying operations, the thread button bit is one of the most critical components in your tool string. A well-chosen button bit directly impacts penetration rate, hole straightness, and overall drilling economy. Yet many operators and procurement teams struggle to navigate the wide range of thread types, face designs, and quality levels available on the market.

This guide walks you through the essentials of thread button bit selection, covers the key factors that affect performance and service life, and explains what to look for when sourcing rock drilling tool products from a reliable supplier.

What Is a Thread Button Bit?

A thread button bit is a percussive drilling tool used in top hammer drilling systems. It features tungsten carbide buttons pressed into a hardened steel body and connects to the drill string via a threaded shank. The bit transfers impact energy from the rock drill through the drill rod to the rock face, crushing and chipping the formation as it rotates.

Thread button bits are widely used in underground mining, surface benching, tunneling, and construction drilling. They are especially effective in medium to hard rock formations where high penetration rates and long service life are required.

Thread Types: R-Series vs T-Series

The thread profile is the first and most important specification to get right. It determines compatibility with your existing drill rods, shank adapters, and coupling sleeves. The two dominant thread families are:

TY Drill Bits offers a full range of thread button bits across all major thread profiles. The R32-51mm 7-button thread rock drill bit is a popular choice for medium-duty tunneling work, while the T38-89mm thread button bit delivers reliable performance in harder formations. For deep hole production drilling, the T51-115mm retrac button bit with ｄｒｏｐ center face design provides excellent flushing and hole straightness.

Face Design: Flat Face vs ｄｒｏｐ Center vs Retrac

The face profile of a thread button bit affects flushing efficiency, button wear pattern, and drilling stability. Three common designs are available:

For operations in fractured or blocky ground, retrac-style bits like the R32-64mm retrac type button drill bit and the T38-76 retrac button bit are strongly recommended. The retrac design includes reverse-cutting edges on the bit body, allowing the operator to ream the hole while pulling back — a critical safety feature when working in unstable formations.

Button Configuration and Carbide Grade

The number, shape, and grade of tungsten carbide buttons determine how the bit performs in specific rock types:

• Spherical buttons: Best for hard, abrasive rock. Offer maximum wear resistance and even stress distribution.
• Ballistic buttons: Sharper profile for faster penetration in medium-hard formations. The pointed shape concentrates impact energy for more aggressive cutting.
• Button count: More buttons (7-9) provide better wear life in abrasive ground; fewer buttons (5-6) deliver faster penetration in softer rock.

Carbide grade selection is equally important. TY Drill Bits uses premium-grade YG11C tungsten carbide for its button bits, balancing toughness and wear resistance for demanding mining applications. The R25-65mm tungsten carbide button bit is a good example of a bit engineered for hard rock with a 7-button configuration and high-grade carbide inserts.

Thread Button Bit vs DTH: When to Choose Which

A common question from drilling contractors is whether to use top hammer thread button bits or dth drilling tool systems. The answer depends on hole depth, diameter, and rock conditions:

TY Drill Bits supplies both thread button bit and dth drilling tool products, so you can source a complete drilling package from a single supplier. The company’s DTH range includes DHD3.5, Cir90, Cir110, and BR2 series hammers and bits for low, medium, and high air pressure applications.

How to Choose the Right Thread Button Bit

When selecting a thread button bit, answer these five questions before placing an order:

1. What is your drill rod thread type? Match the bit thread exactly to your existing rods — R32, T38, T45, T51, etc.
2. What hole diameter do you need? Confirm the required bit diameter for your blast pattern or support design.
3. What rock type are you drilling? Hard abrasive rock requires spherical buttons and higher button count; medium rock can use ballistic buttons for faster penetration.
4. What are the ground conditions? Fractured or blocky ground calls for retrac-style bits. Solid, competent rock works well with standard flat face or ｄｒｏｐ center designs.
5. What is your flushing medium? Air or water flushing affects face design choice — ｄｒｏｐ center faces improve flushing in wet conditions.

What to Look for in a Thread Button Bit Supplier

Not all thread button bits are created equal. When sourcing from a manufacturer, evaluate these critical factors:

TY Drill Bits, established in 2010 in Xi’an, China, meets all of these criteria. The company is ISO 9001 certified, offers OEM services, and exports over 90% of its production to international markets. Its thread button bit range includes R25, R32, T38, T45, and T51 thread profiles with diameters from 45mm to 127mm, covering flat face, ｄｒｏｐ center, and retrac designs.

Maintenance Tips for Longer Bit Life

Proper maintenance can significantly extend the service life of your thread button bits:

• Regular regrinding: Regrind buttons when wear flats reach approximately one-third of the button diameter. Delaying regrinding reduces penetration rate and accelerates bit wear.
• Thread lubrication: Always apply thread grease before coupling to prevent galling and ensure proper torque transfer.
• Inspect between holes: Check for cracks, missing buttons, and thread damage after each hole. Remove damaged bits immediately to avoid string failure.
• Proper storage: Store bits in a dry environment with thread protectors in place to prevent corrosion and thread damage.