The steam drum gasket was incorrectly fitted with an internal steel ring wound gasket. Why can’t internal steel ring gaskets be used?

It may be because the heating expansion of the inner steel ring causes the gasket to loosen

With the same question, I ask authoritative figures to provide an answer

According to the regulations, for raised and recessed flanges with a pressure rating greater than 1.6 MPa, steel inner ring gasketing should (can) be used. (1) Coiled gaskets are suitable for pipelines handling extremely hazardous media, highly hazardous media, flammable media, or those subjected to high temperatures, large temperature differences, mechanical vibration, or pressure fluctuations. The selection of wound gaskets shall meet the following requirements: ① For raised-face flanges with a nominal pressure PN < 6.3 MPa, wound gaskets with an outer ring can be used ； For raised-face flanges with a nominal pressure of PN ≥ 6.3 MPa, wound gaskets with inner and outer rings must be used ； ② For raised and recessed face flanges, gaskets with an inner ring design should be used ； ③ For tenon-and-socket face flanges, basic-type (without inner or outer rings) wound gaskets should be used.

Check the flange of the steam drum; if the flange does not have a male and female surface, then an internal steel ring gasket cannot be used, of course.

The key point is mentioned in the \"Letter from the General Office of the State Administration for Work Safety regarding the urging of corrective actions regarding safety hazards, Document No. An Jian Zong Tang Guan San Han [2018] 27\": \"7. Equipment management is not proper; for example, in the case of the new 15Q18-1 liquid ammonia sphere tank, the xylene storage tank in room V-9101AB, and the feed connection valve of the xylene pump in room P9101A, inner steel-ring wound gaskets were used as sealing gaskets, which is an incorrect choice.\"； Two inner steel-ring wound gaskets were incorrectly installed on the sealing surface of the temperature element connection flange; moreover, inner steel-ring wound gaskets were wrongly used for the heating pipeline connection flange ； ”“, Incorrect use of an internal steel ring wound gasket in the steam drum gasket. ”It does not specify the type of sealing surface for the flange.