For steam pressure reduction, should I choose a “pressure reducing valve” or a “temperature and pressure reducing valve”?
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As the title indicates, the pressure of the steam (saturated steam at 215°C) is 20 kilograms; it needs to be reduced to 10 kilograms of saturated steam (at 184°C). Is it feasible to use a pressure reducing valve for this purpose? According to what I’ve found, the steam temperature also drops after the pressure valve reduces the pressure. Additionally, when reducing 10 kilograms of steam (saturated steam at 184°C) to 4 kilograms of saturated steam (152°C), is it feasible to use a pressure reducer directly in this case? Is it necessary to use a temperature and pressure reducing valve in these two situations? I’d like to ask experienced netizens for advice; thanks in advance!
Generally, connecting a pressure reducing valve directly will result in superheated steam.
In this case, there is no need to reduce the temperature. Generally, when reducing the temperature, one must consider the temperature range required at the subsequent points where the steam is used, the material of the pipes after pressure reduction, and the purpose of the steam after pressure reduction. If the temperature requirements are not strict and the difference between the initial and final temperatures is not significant, it will have little impact on subsequent processes. Moreover, after direct pressure reduction and short-distance transportation, the temperature will quickly drop to that corresponding to saturated steam.
Thank you for the reply and guidance: handshake
Thank you for your reply and guidance; if this works, then there’s no need to use a temperature and pressure reducer.
After depressurization, the steam condensation temperature decreases. The latent heat of vaporization released at the same mass is also greater. Planning can be done by taking your manufacturing processes into comprehensive consideration.
Normally, a pressure reducing valve can be used directly. The working principle of a pressure reducing valve is to reduce pressure by controlling the cross-sectional area through which steam flows in the pipeline. In addition to pressure, the temperature, latent heat, and specific volume of the steam also change. It should be noted that the flow rate of the steam after pressure reduction decreases; therefore, it is necessary to consider the steam consumption of the equipment in the area where pressure reduction takes place in order to select the appropriate model.
Whether to use a \"pressure reducing valve\" or a \"temperature and pressure reducing valve\" depends on the requirements of the subsequent processing steps; if there are restrictions on the steam temperature in those steps, then a temperature and pressure reducing valve is necessary
There is enough piping available later on, so a pressure regulator can be used directly, and the temperature will drop naturally.
Agree with Lcmqh’s reply. Regarding your two questions, if we ignore whether the process temperature is appropriate and consider only the material, then for the second operating condition, it is sufficient to reduce pressure without reducing temperature. For the first operating condition, not reducing the temperature may require the use of a higher-grade material, which is not economical. Specifically, it is necessary to check the pipeline grade table.