Sempell VSE Series User Manual

6
SEMPELL SERIES VSE/VSR FULL LIFT AND NORMAL SAFETY RELIEF VALVE
OPERATING INSTRUCTIONS
For set pressures below 3 bar the closing pressure difference may be up to 0.3 bar.
3.9 FUNCTIONAL DIFFERENCES
VSE 1 Standard
VSE 1 with compensating
pistonSN144
VSR 1 (with adjusting ring)
Standard
VSR 1 with compensating
pistonSN144
Opening pressure difference +5% +3% +3% +3%
Closing pressure difference -10% -10% -8% -6%
VSE 2 Standard
VSE 2 with valve seat
forliquidsSN123
VSR 2 (with adjusting ring)
Standard
VSR 2 with valve seat seat
forliquidsSN 123
Opening pressure difference +5% +10% +3% +10%
Closing pressure difference -10% -20% -8% -10%
Changing the closing pressure difference
forVSR 1 and VSR 2
After removing the lock screw (44), the closing
pressure difference can be changed by means
of the adjusting ring (14). The sum of opening
and closing pressure difference remains
approximately the same.
ATTENTION
Remove lock screw (44) only with lowered
pressure. At operating pressure adjusting the
adjusting ring (14) may lead to unintended
response of the safety valve. When discharging
the safety valve or in case of untight valve
seat, medium may escape out of the opened
adjusting bore. Danger of scalding by hot media,
e.g.steam!
For adjusting, put screwdriver through the
opening and adjust adjusting ring (14) groove by
groove. Its graduation equals about 0.2 mm of
vertical adjustment.
Screw adjusting ring (14) up = closing pressure
difference lowers. Turn in and tighten lock
screw (44) again.
3.10 TROUBLE SHOOTING
Malfunction Cause Remedies
Safety valve opens at different pressures. 1. Condensate in the inlet line. 1. Improve insulation of line. Observe drain and slope.
2. Pressure change by superimposed vibration. 2. Suppress vibrations at the safety valve.
Safety valve opens and closes in rapid
succession.
1. Pressure loss in the inlet line is greater than the closing
pressure difference.
1. For VSR enlarge closing pressure difference. Otherwise
reduce flow resistance of the inlet line: expand, shorten
or remove constrictions. Fast remedy: decrease lift
(asfar as allowed), therefore diminish outflow.
2. Discharge quantity is too small because the subsequent
flow is too small.
2. Install smaller safety valve or adjust discharge quantity.
3. Admissible back pressure is exceeded in the exhaust line. 3. Decrease flow resistance of the exhaust line: e.g. by
expanding or shortening the line.
4. Dynamic pressure drop in the inlet line, especially in case
of liquids.
4. Provide safety valve with a vibration damper.
Closing pressure differences are too great. 1. Saturated steam with high moisture. Adjusting ring (14) of
VSR is not adjusted correctly.
1. For VSR change closing pressure difference.
Safety valve stays open after
dischargetest.
1. Foreign bodies between seat zone (3) and disc (4). 1. Repeat discharge test or blow off foreign bodies by
lifting the lever (36). Otherwise disassemble valve.
Safety valve fails to close tightly. 1. Valve seat damaged. 1. Disassemble valve. Rework valve seat and disc (4).
2. Difference between operating and set pressure is too small. 2. Enlarge difference or mount supplementary loading.
3. Body forming by line forces. 3. Lay line elastically.
4. No slope of the inlet line in case of hot liquids. 4. Assemble inlet line with slope to the safety valve or lay
siphon-type bend.

Sempell VSE Series Specifications

General

Brand	Sempell
Model	VSE Series
Category	Control Unit
Language	English