Page 36
Notice G05 - 3 590 503
Issue: 11/2011 - Rev.A
ERVOR (SCA) - 6, Rue Désiré Granet - Z.I. du Val d'Argent - 95100 ARGENTEUIL FRANCE
(33) 01 34 11 50 00
(33) 01 34 11 50 10
Web : www.ervor.com - Email : info@ervor.com
SET OF PISTON RINGS.
Pistons must be assembled with three new piston rings to run in good condition.
Before mounting cylinders make sure that each gap of the piston ring is rotated 120°
approximately in relation to the gap of the preceeding piston ring.
WEAR OF THE PISTON RING GROOVES
The efficiency of a compressor and its oil consumption depends mostly on the state of piston
rings.
Piston rings must work perpendicular to the cylinder axis and therefore the side play between the
piston ring and its groove should not be too large.
If the wear rate is reached, prepare to change the pistons and piston rings.
CIRCUMFERENTIAL WEARING OF PISTON RINGS
Removepiston rings. Manually place each piston ring perpendicular to the cylinder axis.
Play at cut must not exceed the play indicated below :
Piston ring diameter :
play at cut
- ANTI-LEAK ................................................................ 125mm
1.00mm
- SCRAPER ................................................................. 125mm
1.00mm
- ANTI-LEAK ................................................................ 50mm
0.60mm
- SCRAPER ................................................................. 50mm
0.70mm
OVALITY OF CYLINDERS
Disassemble cylinder heads
Remove the piston to its lowest point to free the cylinder to be checked
Check for ovality and possible scratches inside the cylinder
Change oval or scratched cylinders
Piston rings, pistons and cylinders must be checked every 4000 hours of operating.