How many safeguards do you know when installing a valve?

In the valve installation, to maintain the protection of metal, sand and other foreign body into the valve, damage the sealing cover, need to set up the filter and flushing valve; In order to maintain the compressed air purification, oil water separator or air filter should be installed before the valve. The instrument and inspection valve should be installed when considering the operation condition. To maintain the operating temperature, set up the insulation facilities outside the valve; For the installation of the valve, the relief valve or check valve shall be set. Considering the continuous operation of the valve, it is convenient for the danger, and the parallel system or bypass system is established.
 
Preventive measures: 1, the check valve to prevent leakage check valve or expires medium flow back, cause the decrease of the quality of the products, cause accident consequences, such as check valve set before and after one or two cut-off valve. If two shutoff valves are set, the check valve can be removed and repaired.
 
Protective equipment of the safety valve: the isolation valve is not set before and after the installation method, only in individual cases. Such as medium containing solid particles, affect the relief valve cannot be locked after takeoff, to the relief valve before and after installing a seal gate valves, gate valves should be in the fully open position, gate valve and relief valve directly installed a 3/4 "check valve to the atmosphere. The relief valve needs steam to be heated when the medium, such as the paraffin wax, is in a state of solid state at normal temperature, or when the medium temperature of the light liquid is less than 0 degrees centigrade. The safety valve used for corrosive medium, the corrosion resistance of the valve, considering the corrosion-proof film at the valve inlet. The gas relief valve usually has a bypass valve according to its size, as a manual drain.
 
Protective equipment for the pressure-relief valve: there are generally three forms of the pressure-relief valve installation. Pressure gauges in front and back of the pressure-relief valve are convenient to observe the pressure before and after the valve. The valve also has a fully enclosed safety valve, in case the pressure-relief valve fails, the rear pressure of the valve exceeds the normal pressure, including the rear system. The drain pipe is installed in front of the valve front cutting valve, mainly for the flushing of the drainage river, some using the steam trap. By-pass pipe is the main role after the pressure reducing valve malfunction, close the valve before and after the cut-off valve, open the bypass valve, flow adjustment by hand, temporary circulation effect, in order to repair or replace the relief valve pressure reducing valve. 4. Protective facilities: trap trap edge with by-pass pipe and without by-pass pipe two kinds, the condensate recovery and the condensate does not pay, recycling of displacement, and other special requirements of steam trap, install facilities can be used in parallel form. The trap of the bypass valve, whose main function is to discharge a large amount of condensate when the pipe is running. It is not proper to drain the water with the by-pass pipe when the steam trap is to be repaired, which will cause the steam to go into the backwater system. Normally, you don't have a bypass. Only if the heating temperature is strictly required, the bypass pipe can be used in continuous production.