Hydraulics Level 2 Midterm

Front

Three cylinders are moving in an LSPC hydraulic system. One is operating at 1000 psi, another is operating at 1200 psi, and the other is operating at 1400 psi. The unloading spring is adjusted to 200 psi. What is the pump outlet pressure?

Back

1600 psi

Front

A pre-spool pressure compensator valve senses ____.

Back

the highest signal pressure

Front

The term “pressure compensator” can reference all of the following, EXCEPT: pump control within a variable-displacement pump., type of pre-spool compensated DCV., type of post-spool pressure-compensated DCV., unloader valve

Back

unloader valve

Front

A technician is diagnosing a machine with a malfunctioning PC hydraulic system that is quieter than normal. The technician should search for a ____.

Back

blocked DCV

Front

The Caterpillar G-series scraper’s cushion hitch pump uses a ____ as a PC pump.

Back

pump flow-control spool adjusted until it cannot move

Front

If an open-center hydraulic system is running at a constant 27 gpm and operating at a constant 2875 psi, how much horsepower is it consuming?

Back

45 hp

Front

If an open-center hydraulic system is running at a constant 35 gpm and operating at a constant 2700 psi, how much horsepower is it consuming?

Back

55 hp

Front

Who is correct about open-center hydraulic systems? Technician A: No complex signal network needed. Technician B: Inefficiency due to constant oil flow.

Back

Both A and B.

Front

Which equation is used to determine hydraulic horsepower?

Back

Flow (gpm) × Pressure (psi) ÷ 1714

Front

The term ____ describes a traditional excavator hydraulic pump.

Back

open loop