Reversing valve and impact piston
The reversing valve controls hydraulic oil flow to drive the impact piston back and forth. The guide compares several valve designs: spool-type and tubular valves have a separate valve body, while a sleeve valve works around the piston. A shared name such as “valve” does not establish that parts are interchangeable.
What the accumulator does
The guide describes a high-pressure accumulator storing energy during the piston's return stroke and releasing it during the impact stroke to help supply the required flow. It also helps damp pressure shocks and flow pulsations during valve reversal. A diaphragm accumulator illustration identifies the charging port, nitrogen chamber, diaphragm, upper cover and base.
Configurations and inspection requirements vary by machine. Accumulators are pressurized; qualified personnel should inspect, charge and service them using the manufacturer's procedure.
Identify the correct component
For an accumulator, diaphragm, cover or distribution valve, start with the full rock drill model and version, then search the parts directory by part number. Photos of both sides, connections and the nameplate help with matching; similar appearance alone does not prove fitment.
Source: GLOBMACH Hydraulic Rock Drill Parts Selection Guide, printed pages 64–67.