Page 142 - Introduction to Marine Engineering
P. 142
128 Pumps and pumping systems
Dome cover
Adjusting screw
Spring
Bonnet assy.
Figure 6.15 Relief valve
Quick-closing valves
Oil tank suction valves are arranged for rapid closing from a remote
point by the use of quick-closing valves. The collapsing of the 'bridge'
results in the valve closing quickly under the combined effects of gravity
and an internal spring. A manually operated wire or a hydraulic cylinder
can be used to collapse the bridge.
Valve chests
Valve chests are a series of valves all built into a single block or manifold.
Various arrangements of suction and discharge connections are possible
with this assembly.
Other fittings
Mud boxes are fitted into the machinery space bilge suction piping. The
mud box is a coarse strainer with a straight tailpipe down to the bilge
(Figure 6.16). To enable the internal perforated plate to be cleaned
when necessary, the lid of the mud box is easily removed without
disconnecting any pipework.
