5 Inch DTH BITS

5 Inch DTH Bits in 140–178 mm Diameters

MSD supplies 5 inch DTH bits with MSD5A, DHD350, QL50, MISSION50, and SD5 Bit Shank options. The confirmed product range includes 140, 146, 152, 165, and 178 mm bit diameters.

The listed configurations include convex, flat, and concave face designs. Gauge-button layouts, front-button layouts, button shapes, spline counts, and weights vary according to diameter and Bit Shank. The complete specification should therefore be checked rather than selecting a bit from the nominal 5 inch classification alone.

Available Bit Shanks

The confirmed 5 inch DTH bit range includes five Bit Shank options: MSD5A, DHD350, QL50, MISSION50, and SD5.

Each Bit Shank group is currently listed in 140, 146, 152, 165, and 178 mm diameters.

The required Bit Shank must be confirmed against the exact DTH hammer model or the customer's existing drilling system. A similar nominal hammer or bit size does not establish that different shank systems are interchangeable.

Diameter, Face Design, and Button Layout Options

140 mm configurations — Use a convex-face design with 7 × Ø18 mm gauge buttons and 4 × Ø15 mm plus 3 × Ø14 mm front buttons across all five Bit Shank groups.

146 and 152 mm configurations — Use a flat-face design with 8 × Ø18 mm gauge buttons and 8 × Ø14 mm front buttons across the listed Bit Shank groups.

165 mm MSD5A, DHD350, QL50, and SD5 configurations — Use a concave-face design with 8 × Ø18 mm gauge buttons and 4 × Ø16 mm plus 4 × Ø14 mm front buttons.

165 mm MISSION50 configuration — Uses a flat-face design with 8 × Ø18 mm gauge buttons and 9 × Ø14 mm front buttons.

178 mm configurations — Use a concave-face design with 8 × Ø18 mm gauge buttons and 6 × Ø16 mm plus 5 × Ø14 mm front buttons.

These differences show that the five available diameters are not simply scaled versions of the same design. Face profile and front-button arrangement must also be checked for the selected Bit Shank.

Button Shapes and Spline Differences

MSD5A, DHD350, and SD5 — Listed with 8 splines. Their 140, 146, and 152 mm configurations use Spherical + Ballistic buttons, while the 165 and 178 mm configurations use Spherical buttons.

QL50 — Listed with 12 splines. Its 140, 146, and 152 mm configurations use Domed + Ballistic buttons, while the 165 and 178 mm configurations use Domed buttons.

MISSION50 — Listed with 12 splines. The 140, 152, and 165 mm configurations use Spherical + Ballistic buttons, while the 146 and 178 mm configurations use Spherical buttons.

The parameter table uses Spherical and Domed as distinct button-shape descriptions.

Matching the Bit With the DTH Hammer

The nominal 5 inch classification is only the first selection step. The DTH bit must use the Bit Shank required by the exact hammer model. The confirmed MSD hammer range pairs MSD5A with the MSD5A shank, DHD350 with DHD350, QL50 with QL50, M50 with MISSION50, and SD5 with SD5.

The confirmed hammer hole ranges are Ø136–155 mm for MSD5A and M50, and Ø135–155 mm for DHD350, QL50, and SD5.

Bit Shank matching alone does not confirm the complete configuration. The selected bit diameter must also be checked against the confirmed hole range of the exact hammer model. This is especially important for the listed 165 and 178 mm bit configurations, which exceed the confirmed Ø135–155 mm or Ø136–155 mm ranges of the current 5 inch hammer models.

For replacement orders, provide the complete hammer model, current bit marking, required Bit Shank, required hole diameter, and product photos or drawings before the order is confirmed.

Typical Drilling Applications

These 5 inch DTH bit configurations may be reviewed for mining and blast-hole drilling, quarrying, water-well drilling, construction, and foundation applications where the required diameter and drilling system are suitable. Final selection should still be based on the exact hammer model, Bit Shank, confirmed hole range, formation, and operating conditions.

Information to Confirm Before Ordering

To confirm a suitable 5 inch DTH bit, provide the following information:

Required Bit and Hole Diameter — Required bit diameter and finished hole diameter in millimeters.

DTH Hammer Model — Exact hammer model used in the drilling system.

Bit Shank — Required Bit Shank designation.

Current Product Information — Current bit model or marking, where available.

Reference Materials — Photos or drawings of the current bit and shank.

Required Configuration — Face design and button configuration, if already known.

Working Conditions — Rock formation, abrasiveness, drilling application, and operating conditions.

Order Requirement — Required quantity.

For replacement orders, the existing hammer, Bit Shank, bit information, and confirmed hammer hole range should take priority over a general inch-size description.

Why Choose MSD

MSD is a China-based manufacturer of rock drilling tools supplying DTH hammers, DTH drill bits, drilling components, and related products.

MSD focuses on reliable quality, correct tool selection, and technical support. The objective is not only to supply a bit in the requested diameter, but also to help confirm the appropriate Bit Shank and configuration for the customer's drilling system, helping reduce mismatch risk, unnecessary downtime, and the overall drilling cost per meter.

Technical content reviewed by MSD Engineering Team. | MSD — 23+ years of rock drilling tools manufacturing expertise | ISO 9001 Certified | Exporting to 40+ countries