Explosion protection issues of flameproof instruments
Thread Content
For the electrical interface through which the flameproof instrument cable is introduced, if it is 1/2\" NPT(F), does the instrument come equipped with a flameproof sealing ring? Used for explosion-proof sealing. There is still no sealing ring; does it need to be sealed using an explosion-proof flexible tube together with an explosion-proof sealing joint? Another example is explosion-proof junction boxes, which are generally equipped with explosion-proof sealing joints; in such cases, is it sufficient to use only explosion-proof flexible hoses? Today, an explosion-proof equipment manufacturer asked me a question: since it’s an explosion-proof instrument, it should come with its own sealing ring, and compression alone should be sufficient to achieve sealing – then why is an explosion-proof sealing joint needed? So the key question is whether all explosion-proof instruments come with sealing rings?
Hehe~ It’s so scary! What should I do if I don’t understand? :L
In my understanding, explosion-proof instruments do not come with sealing joints. An explosion-proof instrument means that the instrument itself meets a certain explosion-proof rating; if you use explosion-proof flexible tubing, then sealing joints are not necessary. Of course, if you do not use such flexible tubing, sealing joints are required, along with the addition of explosion-proof sealant.
Thanks for the top post! How about you mention it again at 0.5 yuan? It’s a small issue, but not many people on the forum know about it.
Is there anyone else who wants to discuss this issue?
In fact, modern explosion-proof flexible hoses and explosion-proof cable sealing joints (cable sealing joints are also known as glands; in English, they are called Cable Glands) all come equipped with explosion-proof seals. In other words, if one does not have the instrument manufacturer provide the gland and instead purchases the explosion-proof flexible hose or gland separately, it doesn’t matter whether the instrument itself has an explosion-proof seal or not. However, since the electrical connectors need to be sealed at the time of factory production, some manufacturers simply use a simple plastic gland along with a sealing ring to seal the electrical connectors. However, this sealing ring may not be suitable for the explosion-proof hose or gland fitted with that instrument. Additionally, a correction for the 4th floor: Explosion-proof cable seals are sealed and provide explosion protection through their sealing rings, whereas explosion-proof putty is used in situations where there are no such cable seals or explosion-proof flexible hoses, such as at the points where cable trays enter or leave a building, as well as in conduit systems without sealing joints and the cables inside them.
If you have any questions regarding explosion protection, I have professional experts in this field at my disposal (Director Chen from Nanyang Explosion Protection Research Institute); they should be able to help you!
I don’t think I’m wrong; when using sealed connectors, the section from the cable to the protective tube needs to be covered with explosion-proof putty, otherwise the end of the protective tube will wear out over time and may even cut the cable
Study the relevant standards carefully; GB 3836.2-2010 Explosive atmospheres – Part 2 and GB 50093-2013 contain all the answers to this issue.
What you’re talking about has nothing to do with explosion protection; it’s a simple issue of cable protection. The installation manuals for automatic control systems require the use of cable guards, but in many cases, explosion-proof putty is used instead
It has nothing to do with explosion protection; I use this explosion-proof putty to prevent the cables from suffering severe wear due to pulling