Selection of manholes for jacketed vessels
Thread Content
Dear Haihao friends: Recently, a jacketed container has been designed, with normal pressure inside the container and 0.4 MPa in the jacket. A DN500 manhole must be installed on the container; can a manhole at atmospheric pressure be used for this purpose?
A manhole at normal pressure can be selected, as the welding joint type between the manhole and the inner cylinder can follow the pattern shown in a) of Figure 25 in Appendix D of GB/T150.3-2011. The manhole has no connection to the jacket.
The manhole must be selected based on the medium inside the inner cylinder and the required gasket; if a wound gasket is to be used, a manhole with a neck is necessary. Multi-chamber containers have requirements based on their respective parameters; therefore, if the medium inside the inner cylinder is non-hazardous, a normal-pressure manhole can be selected.
The design specified in a) of Figure 25 in Appendix D of GB/T150.3-2011 has been found. Thank you!
Which standard specifies the criteria for selecting manholes based on the requirements of the medium inside the inner cylinder and the gasket? I’d like to find the source, thank you!
For example, if it is a highly hazardous medium, a normal-pressure manhole cannot be used...
No specific source. Atmospheric pressure manhole flange types are not suitable for highly hazardous media...
Since it is not a highly hazardous medium, can a normal-pressure manhole be used?
You’re welcome; it’s just a humble opinion. :)
1. NB/T 47003.1 \"Welded steel pressure vessels at normal pressure\" is not applicable to vessels used for containing extremely hazardous or highly hazardous media. This comes from page 5, clause 1.3 of the standard. Therefore, atmospheric pressure manholes certainly cannot be used in conditions involving extremely hazardous or highly dangerous media. 2. In the original poster’s question, the operating temperature of the container was not mentioned. Please note page 37 of the HG/T21515-2014 standard \"Manholes at Atmospheric Pressure\", which specifies the maximum allowable operating pressure and operating temperature applicable to this standard.