1. full stroke safety device
The sectional drawings show the internal construction of the two mainly used valve types. Safety valves are important safety devices and must prevent high excess pressures in the boiler. To ensure that they will operate reliably, they must be carefully maintained and the operating instructions strictly observed. Only type-tested safety valves must be used. With the full-stroke safety valve the required valve stroke is already reached at a 5% excess pressure. With such valves the opening takes place suddenly at the start of blow-off, also closing after pressure has dropped sufficiently.
2. Assembly instructions
The blow-off pipe run must be laid safely into the open. The pipe cross-section must be chosen so that no back-pressure occurs at full blow-off . The attachment must be made to ensure that occurring back-pressure forces can be safely absorbed. Even in the closed condition, no additional forces from the blow-off piping must act on the safety valve. Provide enough brackets on the blow-off pipe! The blow-off pipe must have a safe outlet and be safeguarded against freezing. The blow-off pipe must be provided at its lowest point with a drainage unit which cannot be shut off. Blow-off pipes of safety valves which are connected to water spaces must be provided with an expansion vessel and a water trap.
3. Setting
The response pressure setting is checked and lead-sealed by the inspector during the safety test. When setting the response pressure of a spring-loaded safety valve care must be taken that the taper does not turn at the same time. To prevent this, the spindle must be held tight when adjusting the spring compression screw. On completion of the pressure setting the spring compression screw must be secured.
4. Checking for easy movement
Safety valves must be checked at appropriate intervals for easy movement. To do this, the load on the taper must be relieved by raising the lifting lever, so that the valve opens at the existing operating pressure.
The sectional drawings show the internal construction of the two mainly used valve types. Safety valves are important safety devices and must prevent high excess pressures in the boiler. To ensure that they will operate reliably, they must be carefully maintained and the operating instructions strictly observed. Only type-tested safety valves must be used. With the full-stroke safety valve the required valve stroke is already reached at a 5% excess pressure. With such valves the opening takes place suddenly at the start of blow-off, also closing after pressure has dropped sufficiently.
2. Assembly instructions
The blow-off pipe run must be laid safely into the open. The pipe cross-section must be chosen so that no back-pressure occurs at full blow-off . The attachment must be made to ensure that occurring back-pressure forces can be safely absorbed. Even in the closed condition, no additional forces from the blow-off piping must act on the safety valve. Provide enough brackets on the blow-off pipe! The blow-off pipe must have a safe outlet and be safeguarded against freezing. The blow-off pipe must be provided at its lowest point with a drainage unit which cannot be shut off. Blow-off pipes of safety valves which are connected to water spaces must be provided with an expansion vessel and a water trap.
3. Setting
The response pressure setting is checked and lead-sealed by the inspector during the safety test. When setting the response pressure of a spring-loaded safety valve care must be taken that the taper does not turn at the same time. To prevent this, the spindle must be held tight when adjusting the spring compression screw. On completion of the pressure setting the spring compression screw must be secured.
4. Checking for easy movement
Safety valves must be checked at appropriate intervals for easy movement. To do this, the load on the taper must be relieved by raising the lifting lever, so that the valve opens at the existing operating pressure.
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