Summary
The 2600P series of regulating valves adopt external pressure equipment, which can achieve self-adjusting and pressure stabilizing by pressure change of the media itself. And it can be applied in the places with steam, non-corrosive gas and low sticky liquid, as well as the maintaining pressure below 1.6MPA.
This series has two modes: front-valve(2601P) and back-valve(2602P)
As self-operated pressure regulating valve doesn’t need other exterior energy like power, gas which can be operated only by its own energy of the media, it can not only save energy but also environmental. It can be automatically operated by setting the pressure value after installation, so it is used more and more widely in the places which lacks of power and gas sources and has low control precision.
As self-operated pressure regulating valve doesn’t need other exterior energy like power, gas which can be operated only by its own energy of the media, it can not only save energy but also environmental. It can be automatically operated by setting the pressure value after installation, so it is used more and more widely in the places which lacks of power and gas sources and has low control precision.
This valve should be chosen and installed properly to make sure everything goes well during operation. As for choosing the right type, you need to consider the regulating valve is used to regulate the pressure pre-valve or after valve; and the media is with normal temperature or high temperature; the media is with corrosion or not; what’s the max working pressure etc. All these issues need to be identified before installation. Hereby let’s discuss about the installation problems. Recently I met a typical case of use of self-operated pressure regulating valves.
The valve is used in the steam pipe, and only one month after installation that the user reported there is something wrong. When reaching the spot, I found that a lot of steam release from the gas-releasing hole of the membrane head of the regulating valve, and the noise is very loud. As for the reason, obviously the steam is not cooled and condensed but directly get into the membrane, so it burns out the membrane.
When use the self-force pressure regulating valve in steam pipe, a condensing tank between the operator and pipe should be added to prevent the steam directly from getting into the membrane of actuator. And the regulating valve should be installed with the head downward; the condensing tank should be installed higher than the head of membrane. And when it is used for the first time, the condensing tank and membrane should be fully filled with water. After checking the installation in site and asking the installment person, all the above issues have no problem at all. So what’s the reason then? When I asked an operator carefully, I get the information that after the valve is installed, the copper pipe joint between condensing tank and membrane head is leaking continuously. Then I found out the reason: the water in the condensing tank leaks gradually, and the steam gets into the head of membrane, so that it burns out the membrane.
So, when the self-force regulating valve in steam pipe is used, attentions should be paid to the installation and maintenance to make sure that the regulating valves operate normally. Prevent the water leakage and make sure there is enough water in condensing tank. Operators should check regularly and add water from time to time. Actually, both for the self-operated regulating valves and other self-operated regulating valves, they should be properly maintained and repaired when using.
In addition, when the pressure of steam is fairly high, it is preferred to choose piston actuator instead of thin film one, because the membrane can only withstand the pressure not more than 0.4Mpa . When it is used above this pressure, though it can be used, the life of valve will be decreased dramatically.