CHAPTER 6. REPAIR OF RECIPROCATING PUMP GEAR CASE

R E P A I R OF RECIPROCATING PUMP GEAR CASE

gear is keyed to the ball-bearing-mounted

Description

crankshaft which drives the pump plunger and

a. The pump gear case provides the torque

diaphragm assembly. The total speed reduction

multiplication and speed reduction necessary to

through the gear case is approximately 61:1. If the

drive the pump plunger at the rate of speed

engine is operating at 3000 rpm, the pump plunger

necessary for efficient operation. The coupling half,

will cycle approximately 49 times per minute.

which is driven by the engine, is mounted on the

c. The gear case in which the shafts and gears

input shaft of the pump and drives the gear case at

are installed is sealed and contains gear oil to keep

engine speed. This input shaft has integral pinion

the parts lubricated. The lubrication fitting on the

teeth which engage the internal gear to provide an

lower side of the case regulates the level of lubricant

initial speed reduction of 8.083:1.

which can be poured into the case.

b. The internal gear is pressed onto and drives a

pinion shaft. This pinion shaft is roller bearing

6-2. Disassembly

mounted in the housing and drives a spur gear.

a. Disassemble the gear case following the

T h i s engagement provides the second speed

sequence shown in figure 6-1.

reduction, this one having a 7.56:1 ratio. The spur

6-1