A49Y-PW5414V冲量安全阀

The impulse safety device is the main safety valve, with auxil-iary valve
support contained. This device has characteristics as large discharge ability,
convenient adjustment, dual mechanical and electric protection and few workload
in installation and maint-enance.
This device is used for inlet and outlet
pipe of reheater to avoid mediun pressure exceeding the allowable value to
ensure the reheater shall run safely.
1.The impulse safety device is as shown
in the figure, mainly consisted of impulse safety valve, the main safety valve,
stop valve and throttle valve. Impulse safety valve is a kind of spring safety
valve. It is mainly consisted of body , bonnet, disc and other parts.The impulse
safety valve can be adjusted by using the spring to regulate the
pressure.
The impulse safety valve contains an electromagnet to open and
another to close the valve. The actions of the mechanism and the electric
appliance are separate and will not affect each other .
2.The main safety
valve is as shown in the figure. With astructure of single exhaust and both ends
of flange connection, it is mainly consisted of body, bonnet, piston chamber,
disc, stem and other parts.
3.Both the sealed surfaces of disc and seat of
the impulse safety valve are made of hard alloy of cobalt by overlaying welding
Both the seat and the disc of the main safety valve are made of hard alloy of
cobalt by plasma spray welding.
4.The upper part of the impulse safety valve
contains an elec-tromagnet to open and another to close off. At ordinary times,
the close-off electromagnet may not be electrified, but when the sealed surface
of the valve leaks or when the mechanical addition adjusting reseating pressure
is excessively low, it can be electrified by closing electromagnet to make valve
sealed or help the valve clack return and procure a higher seat reseating
pressure.
5.The impulse safety valve only leaves the factory after it has
passed the seal and sensitivity tests, proved to be qualified.
When the
medium pressure inside the reheater exceeding the allowable value, the impulse
safety valve opens firstly; the steam enters into the piston chamber of the main
safety valve, forcing the main safety valve to open; the reheater bengins
discharging steam;after the excess pressure has been released, the impulse
safety valve closes, stopping the steam entering into the piston chamber of the
main safety valve; the main safety valve automatically colses at the reactions
of the spring and
medium.