Does the setting of the safety valve need to take into account the motor power?
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Sir, for a compressor unit, does the setting value of the safety valve on the exhaust side need to take into account the motor power? Because some people say that the setting value for the safety valve to activate is 1.1 times the operating pressure, and the motor power must not exceed this value at that time. I’m puzzled; if the safety valve is set in this way, it will still leak slightly, because the sealing test pressure for a safety valve is 0.9 times the set pressure. And if the set value is higher, while it is still required that the motor operates properly, then the motor power will be too high, resulting in poor cost-effectiveness. Please ask an expert for advice!
I’m not quite sure; a safety valve is presumably a safety device that releases pressure when overpressure occurs, and the key parameter is the setting pressure at which it activates
It has nothing to do with the electric motor! Look at how much pressure you use to jump! For piston-type units, it should not exceed 1.54 megapascals at high pressure, 1.85 megapascals at very high pressure, and 1.25 megapascals at low pressure
Based on my personal understanding, this is regarding the requirements for the discharge volume; for reference only
Of course it needs to be taken into consideration. The pressure at which the safety valve activates must be higher than the normal operating pressure; in other words, the backpressure is higher. Under the same inlet conditions, a higher backpressure means that the piston force will be greater than normal. If the piston force is increased, then without considering the motor power, it won’t be possible to drive the system Another point is that increasing the power of the motor is equivalent to choosing a motor of a higher capacity; the actual energy consumption is related to the effective power of the machine being driven. In other words, choosing a motor with higher capacity only increases the initial investment, without affecting the subsequent energy consumption. It has nothing to do with the power level of the motor.
For reciprocating pumps, API618 sets out the required specifications. Moreover, the setting error of the safety valve must also be taken into account; it is generally plus or minus 3%. The safety valve serves to protect the containers and pipelines, so the set pressure * 1.03 must not exceed the maximum operating pressure of those containers and pipelines.
The safety valve is installed to prevent overpressure and protect the equipment; it has nothing to do with the motor’s power
It doesn’t seem to matter that much, right?
The selection of motor power requires consideration of the operating conditions under which the safety valve operates, in accordance with API 618 clause 7.1.1.3: The drive unit must be capable of operating the compressor with all stages at full flow, while also allowing discharge at the pressure set by the relevant relief valve.