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Page 23
4990497003 Date: 11/2016
TR20 Installation, Operating & Maintenance Manual
5.3
Valves
Check Valve
The check (non-return) valve should be removed and visually checked for signs of
wear. If in any doubt, replace the entire valve.
Relief Valve
The screwed top of the relief valve (lifting screw) can be used to check/clear
the relief valve during operation. This removes the necessity for using
seperate ancillaries/valves in the discharge line making checking much
easier and faster. With the compressor operating at greater than 85% of its
pressure setting:-
Setting
85%
2 bar(g)
>1.7 bar(g)
2.2 bar(g)
>1.87 bar(g)
Operation / Function Test
1.
Rotate the lifting screw ACW until a clear, audible, air discharge is
produced.
2.
Rotate the lifting screw CW until it reaches the limit stop.
The valve is now checked and ready for operation.
New gaskets may be required
when inspecting the check
valve.
NOTE
5.4
Silencers / Pipework
The silencers and pipework should be inspected for signs of damage
or corrosion. When paintwork is damaged, clean off any corrosion and
treat with rust inhibitor before repainting. Use paints that can withstand
temperatures of 180°C.
Maintenance
Figure 13. Relief Valve
Lifting Screw
Lifting Screw