Problems with safety valves
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I saw today that an A21H-16C model is being used in a reaction vessel. After checking, it turns out that the A21F and A21H-C models are suitable for equipment or pipelines handling media such as air, ammonia, petroleum gas, etc., at working temperatures of up to 200°C. However, the operating temperature of my reaction vessel is well above 200°C. Is there a problem with the selection of the model? Secondly, I see that the safety valve indicates a set pressure of 0.4 MPA at a pressure of 1.6 MPA, but the one installed outside shows a set pressure of 0.095 MPA. What does this mean? Is the one on top expired?
Selective error, or it’s borrowed; the pressure should be positive definite twice
The nameplate on the safety valve indicates the set pressure at the time of manufacture (0.4 MPa) and the nominal pressure (1.6 MPa). There is a lead seal attached, along with a plate on which the pressure after re-setting by the local technical supervision authority is indicated (0.095 MPa). This shows that the operating pressure of your reactor is very low; it’s clear that the safety valve is a substitute part, as its design temperature is insufficient.
I think its applicable conditions aren’t met either! What type do you think I should choose? Why is pressure setting done twice, and which one should be taken as the standard?
What does \"replace the safety valve\" mean? Basically, this reaction vessel was originally a pressure vessel; it is said that its status as such was revoked, and now it is no longer considered a pressure vessel, so it is no longer subject to regulation! It’s been over five years since it was canceled
It means that no design for the pressure vessel was carried out; instead, a safety valve was simply used as a substitute (one that might have been taken from another pressure vessel or something similar). Of course, it’s also possible that the pressure vessel itself wasn’t designed properly, which is why the safety valve doesn’t match the design temperature of the vessel. Based on what you’ve described, this reaction vessel is a very old piece of equipment with low pressure, and it falls outside the scope of regulation outlined in TSG R0004-2009 \"Safety Technical Inspection Regulations for Fixed Pressure Vessels\".
Since it isn’t a pressure vessel, can I do without a safety valve? With a safety valve installed, it really feels like a pressure vessel!
The safety valve had a high pressure at the time of manufacture; as operating conditions changed, the pressure decreased and it was recalibrated accordingly
This post was last edited by altpage on 2016-3-13 at 16:21. Installing a safety valve may be required either as part of the safety equipment for pressure vessels or due to the process conditions; it is necessary to analyze the specific process conditions and the medium used in this reactor. What type of reaction is it? High temperature and low pressure?
The original set pressure of the safety valve was 0.4 MPa; it was readjusted to 0.095 MPa for use, and such a safety valve no longer possesses its original triggering capability. For a standard safety valve, the adjustment range for a single spring is 10%; such a large change in the set pressure requires the replacement of the spring.
I often encounter problems with safety valves; I suggest checking the relevant standards, as they seem to be quite strict