BHI HydroRam HK300S, Operations Manual & Parts List

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BHI
Best Hammer Industries
- 12 -
2. Principles of Operation
The relation between the area(A2) affecting the pressure from the upper chamber of
the piston and the area(A1) affecting the pressure from the lower chamber of the
piston is A2>A1 and high pressure applies to A1. When A2 changes from high to low
pressure or vice versa, piston (E) reciprocates. Inside of head cap is charged with the
high pressure N2 gas and gas energy stored in the upstroke of the piston (E)
effectively acts on the piston (E) during the impact.
1) Upstroke of Piston
As high pressure always applies to A1 and
A2 changes to low pressure, the force affects
the Piston(E) upward until it reaches to Cylinder
Converting Port(P2). While Piston(E) moves
upward, it is compressing the gas contained in
the head cap chamber. As high pressure applies
to Valve High Pressure Port(B1,B2) and Valve
Converting Port(B4) converts to low pressure,
Valve(K) remains in the down position.
2) Valve Shift
When the area (A1) of the lower chamber of
the Piston(E) reaches to the chamber of the
Cylinder Converting Port(P2), the chamber of
the Cylinder Converting Port becomes and
remains high pressure. Cylinder Converting
Port(P2) communicates with Valve Converting
Port(B4) and delivers the high pressure oil.
When the area(V1) of the Valve Converting
Port(B4) applies to high pressure, Valve(K)
moves upward and shifts. Then Valve High
Pressure Port(B2) communicates with Upper
Port(P4) of the Piston and oil being pressurized
is admitted to Upper Chamber of the Piston.