In the last piece, we learned the old and new standard for anti-static chemical hose. While the new standard adds another 2, Ω/T and M/T. Then what’s the difference among them on usage? Before talking this, let’s learn the classification of service environment.
Definition of explosion-proof area
The air combines with flammable substance and exists as gas, steam or moisture. Besides, it appears frequently and exist for long term.
Same with Grade 0. But it seldom appears.
Same with the above 2 grades. But it will not appear on normal cases. Although happens, it will not exists for a long time.
Knowing the explosion-proof area, let’s see the general explosives
IIA: benzene, TOL
IIC: acetylene, hydrogen
Now, we can map these marks on chemical hose to service environment one by one.
Ω/T means high demand to security
The chemical hose is conductive rubber compound. While the resistance value is 109Ω on the hose wall. Thus it’s suitable for explosive mediums in dangerous area. While the dangerous area means the whole chemical hose works in the explosive area. As for the medium, it’s suitable for IIB and IIC. Besides, it’s also suitable for non-conductive chemicals.
Ω means highly safe
This kind of chemical hose is for normal use. For example, the liquid of IIA. However, if part of the hose is in the dangerous are. For example, only the connector is in the explosion-proof area. The hose still works.
On the most occasions, you can use M/T chemical hose as Ω/T hose. However, the conductive property needs a metal conductor. But the connection of metal conductor is limited by the high fluid load. Then it may shut off in some cases. Thus it’s necessary to test the resistance if chemical hose regularly. Further more, you’d better not use M/T chemical hose if there was any stray current.
M mark means you can use the hose at normal conditions. For example, IIA liquid. But it has the same limits with M/T hose.
After reading this article, do you have a clear knowledge to the 4 marks? If you want to learn more, just contact OrientFlex.