Issues regarding the installation location of steam traps and control valves, as well as the selection of pressures before and after the valves

The control valve should be located on the steam line at the inlet; the pressure before the valve is the steam pressure, while the pressure after the valve depends on the temperature of the condensate water.

Place the steam trap in front of the control valve； Steam is definitely not needed; water is what’s required. The pressure entering the drain tank is 0.1 MPA, so it needs to be adjusted to 0.1 MPA using a control valve ； Water that cannot be regulated before the valve can be discharged through the steam trap ； The pressure before the control valve is the pressure resulting from the liquefaction of 300-degree steam, which is below 0.8 MPa; the pressure after the valve is 0.1 MPA, which represents the properly set pressure

Hydrophobization should be done first, and then the level of hydrophobicity should be controlled

What was said on the 2nd floor is correct: place the control valve on the steam pipeline, and the trap on the condensate pipeline – that’s all that’s needed. The control valve should be designed based on the steam pressure, while the trap can function properly at a pressure of 0.1 MPa for the condensate；

I don’t understand what that means. If these two valves are placed on the same line, won’t steam flow be blocked?

However, the owner wants the control valve to be installed on the drain side, in order to regulate the entire system by controlling the water flow rate. It is currently impossible to determine the pressures before and after these two valves, making it difficult to select the appropriate valves.

First of all, thank you for your answer. According to what you said, the pressure before the steam trap should be approximately equal to the steam pressure, and the pressure after the steam trap should be equal to the pressure before the control valve. So how is the pressure after the steam trap determined? Currently, the main difficulty lies in selecting these two types of valves.

Well, it’s to prevent steam from entering the tank. The main issue right now is that it’s not clear what the pressures before and after these two valves are Not sure how to choose a valve?

The control valve is located at the outlet of the heat exchanger, and the P1 value for this control valve is 0.8. No hydroscoper is required. The control valve is located at the inlet of the heat exchanger; the value of P2 for this control valve is equal to \"the saturated pressure corresponding to the calculated steam temperature of the heat exchanger.\" For those that require a hydroseparator, their P1 is roughly equal to the P2 of the control valve. The above condensate is a gas-liquid two-phase mixture. If full condensate is required, then the condensate on the heat exchanger side is designed as – accumulated liquid + subcooled liquid; no steam trap is needed for the subcooled liquid, only a control valve. There are two questions. According to the owner’s plan, the control valve is located at the outlet of the heat exchanger; then, which process parameter controls this control valve? How is the heat load of a heat exchanger adjusted? @jiaguoyun

Thank you very much for your answer. Our heat exchanger uses steam to raise the temperature of the air in the air ducts, thereby ensuring the desired outlet air temperature. However, some of the steam does not participate fully in the heat exchange process; this steam, along with water from other pipes, can cause water hammer effects. Therefore, a drain valve is installed after the heat exchanger. The control valve is mainly used to regulate the outlet air temperature.