In explosion-proof areas, is it necessary to use explosion-proof hoses in the section where wires are connected?
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In explosion-proof areas, is it better to use explosion-proof hoses at the section where the wires are connected, or can the ends of the steel pipes simply be sealed with sealing materials? Is that one better? This post was last edited by marry on 2009-4-21 15:26.]
Need I say it? Of course, an explosion-proof hose should be used. For extra precaution, a wire should be added at both ends of the explosion-proof hose to prevent static electricity.
However, the common practice abroad is to avoid using hoses; instead, the openings of the steel pipes and the junction boxes are sealed tightly, which means that a section of the cable remains exposed! Of course, I heard about it too.........
Many installers keep bringing up the regulations to us; we don’t know what to do. As long as it can provide explosion protection, that should be fine, right?
The effect should be the same as long as it can be sealed; however, it doesn’t look very good in terms of appearance
What I see the most of are explosion-proof hoses
Explosion-proof hoses are primarily used to protect cables. The quality of domestic cables is currently very poor; without protection, these cables will get damaged within a few years. Our first phase of the project was introduced from the UK in the 1970s; all the cables were installed openly, and they are still in good condition to this day.
It’s not necessary to use explosion-proof hoses; it’s sufficient to ensure that the steel pipes are properly sealed. That’s exactly what we do
Our unit usually uses mortar for direct sealing. Some of the imported equipment in our unit is also sealed with mortar according to the instructions. As long as it is properly sealed, that’s fine.
Use a cable sealing joint! With a hose, I think it’s just a different design philosophy.
Flexible explosion-proof hoses are a good choice, but they cost several hundred dollars each; it’s also possible to seal things with mortar directly. The decision depends mainly on the size of the cable and the interfaces of the wiring connectors.
Sealing the steel pipe outlets with explosion-proof putty, and using quick connectors at the instrument wiring entries – I think this is the best approach, and it also doesn’t violate any regulations.
It is clearly specified in the GB50093-2002 Code for Construction and Acceptance of Instrumentation. When connecting the protective tube to instruments, sensing elements, electrical equipment, junction boxes, and pull box assemblies, or when it enters instrument panels, cabinets, or boxes, explosion-proof sealing fittings must be installed and properly sealed. The distance between such sealing fittings and the instrument boxes, junction boxes, and pull box assemblies should not exceed 0.45 meters. Flexible tubes can be used to connect the sealed fittings to instruments, sensing elements, and electrical equipment. The entire protective tube system must be sealed. It can be seen that the regulations do not require the use of explosion-proof hoses, but proper sealing is necessary.
If armored cables are used, they can be directly connected to the explosion-proof junction box using explosion-proof connectors. If it is a regular wire, from the perspective of protection reliability, it is better to connect the steel pipe directly to the explosion-proof box. For the sake of ease of installation, it is better to use explosion-proof hoses, but care must be taken regarding their quality; stainless steel ones are recommended, as those with a rubber outer layer tend to age more easily.
Of course, an explosion-proof hose should be used. For extra precaution, a wire should be added at both ends of the explosion-proof hose to prevent static electricity.
It’s also popular in China these days, but armored cables are generally used for this purpose – to provide protection against damage. When cables are fed into the box, it’s important to ensure that the armored layer and the shielding layer are properly separated and do not come into contact with each other.
However, the common practice abroad is to avoid using hoses; instead, the openings of the steel pipes and the junction boxes are sealed tightly, which means that a section of the cable remains exposed! Of course, I heard about it too.........
I don’t think so; what we do is use riot control putty.