RC Hammers

RC Hammers and Reverse Circulation Hammers from 3 to 10 Inch

An RC hammer, also called a reverse circulation hammer or RC drilling hammer, is a down-the-hole impact hammer designed to return rock-chip samples through an internal passage.

MSD supplies RC hammers in seven confirmed size classes: 3, 4, 5, 5.5, 6, 8, and 10 inch. The current range contains 12 hammer models covering confirmed hole ranges from Ø84 to 370 mm, with listed working pressures of 1.5–3.5 MPa.

When contractors request an RC drill hammer, the complete specification still needs to be confirmed. Each model has its own Bit Shank, drill-pipe connection, length, hole range, and weight, so nominal hammer size or hole diameter alone does not establish compatibility.

RC Hammer Configuration Differences

The 3 and 4 inch RC hammers each use a confirmed RE-series Bit Shank, but their drill-pipe connection configurations differ.

The 5 and 5.5 inch ranges contain several RE- and PR-series Bit Shanks. Selected models use model-specific Remet or Metzke drill-pipe connection configurations, allowing the required hammer to be reviewed against the existing RC drill string and rig standard.

The 6, 8, and 10 inch models use model-specific RC-series Bit Shanks. Their connection specification must be confirmed according to the exact drill-pipe thread before quotation or production.

The parameter tables should be used to compare the actual model, Bit Shank, connection thread, hole range, working pressure, length, and weight. These fields should not be treated as interchangeable between models.

How a Reverse Circulation Hammer Works

A reverse circulation hammer uses compressed air and bottom-hole impact to break the formation. Its main difference from a conventional DTH hammer is the cuttings-return pathway.

In a typical RC system, the hammer works with a purpose-matched RC bit, a center sample passage, and dual-wall drill pipe. Newly produced rock cuttings enter the central return path and travel upward through the inner tube for collection at the surface.

This configuration helps separate freshly cut sample material from the borehole wall after it leaves the bit face. Actual sample quality still depends on the complete drilling system, connection sealing, formation, groundwater conditions, operating procedure, and surface sample-collection equipment.

Matching the RC Hammer With the RC Drilling System

An RC DTH hammer should be selected as part of a complete reverse circulation drilling system rather than as an independent component.

The main system elements normally include:

• RC hammer

• Matching RC bit

• Dual-wall drill pipe

• Drill-pipe connections and adapters

• Rig and rotation head

• Compressor

• Cyclone or sample-collection system

A mismatch in Bit Shank, connection thread, air supply, or sample-return components may affect drilling stability, cuttings return, sample recovery, and tool operation.

The final hammer configuration should therefore be reviewed against the target hole diameter, drill-pipe thread, compressor pressure and air volume, expected depth, formation, rig setup, and sampling requirements.

Typical RC Drilling Applications

RC hammers are commonly used in drilling programs that require rock-chip samples for geological or operational evaluation.

• Mineral exploration

• Resource-definition drilling

• In-pit grade control

• Geological sampling

• Selected geotechnical investigation

When chip-sample recovery is not required, a conventional DTH system may provide a simpler drilling configuration. The final choice still depends on the hole, formation, drilling method, sampling objective, and overall project requirements.

Information to Confirm Before Ordering

To confirm a suitable RC hammer, provide:

Required Hole Diameter — Target finished-hole diameter.

Hammer Size or Current Model — Required size class or existing hammer model.

Bit Shank — Required RE-, PR-, or RC-series Bit Shank.

Drill-Pipe Connection — Exact Remet, Metzke, or other drill-pipe thread and connection dimensions.

Rig Configuration — Rig model, rotation head, adapters, and current drill-string arrangement.

Compressor Capacity — Working pressure and available air volume.

Drilling Conditions — Expected depth, formation hardness, abrasiveness, groundwater conditions, and existing drilling problems.

Sampling Requirements — Sampling purpose, sample-return requirements, and surface collection-system details.

Current Product Information — Existing hammer markings, drawings, dimensions, photographs, or previous order information.

Order Requirement — Required quantity.

For replacement orders, the existing hammer model, Bit Shank, drill-pipe thread, and connection dimensions should take priority over the general nominal size.

RC Hammer Manufacturer and Supplier

MSD is a China-based RC hammer manufacturer and supplier providing reverse circulation hammers, matching RC bits, and related rock-drilling tools.

The MSD team reviews RC hammer requirements according to the complete drilling configuration rather than only the requested size. Important factors include the Bit Shank, drill-pipe connection, compressor capacity, rig setup, target hole diameter, expected depth, formation, and sampling requirements.

This review helps reduce the risk of ordering an RC hammer or reverse circulation hammer that does not match the existing drill string or operating conditions.

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