Page 356 - The Tribology Handbook

c15 Total loss oil and fluid grease svstems

Single line - volumetric injection
Operation. The pump delivers lubricant under pressure
to a single line main at timed intervals. When the pressure
reaches a predetermined level, each injector or positive
displacement unit delivers a fixed volume of lubricant to
its bearing through a tailpipe.
When full line pressure has been reached the pump
stops and line pressure is reduced to a level at which the -wx -
injectors recharge with lubricant ready for the next cycle.
Pumps are generally electric gear pumps or pneumatic
piston type. All automatic systems are controlled by
adjustable electronic timers but hand operated pumps are
available.
Main lubricant pipework is normally in 6 or 12 mm
sizes and tailpipes in 4 or 6 mm depending the size of
system.
Applications: All types of light to medium sized manu-
facturing plant and commercial vehicles.

Specification:
Outlets: 1-500 (0.005-1.5 ml) Figure 15.5
Pressure: 2-5 MN/m2
Lubricants: 20 cSt oil to NLGI 000 grease.
Failure warning: Main line pressure monitoring.
Cost factor: Medium

a ‘‘L POSITIVE
DISPLACEMENT
BEARINGS UNITS

Figure 15.4

Figure 15.6 Positive displacement unit

C15.2