Relevant regulations on explosion prevention for methanol storage areas that represent major hazard sources
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The methanol tank area requires additional isolation valves, as well as cables, instrument air, and other such items. Are there any regulations regarding the explosion-proof rating or safety requirements for these elements?
Yes, according to the explosion protection regulations, Appendix C: methanol is classified as grade IIA with an ignition temperature of T2; therefore, the explosion-proof electrical equipment used must be of grade IAT2 or higher.
For cut-off valves, it is possible to specify the explosion-proof rating required from the manufacturer; but how is the rating for cables and cable trays determined? The explosion-proof rating of such electrical components must be equal to or higher than IIAT2
Refer to GB50058-2014 \"Code for Design of Electrical Installations in Explosive Atmospheres\" Section 5.4 Design of Electrical Circuits in Explosive Environments
Thank you. I’ll first look for the specifications
I don’t understand. If we use fiberglass cable trays, 2*1.5 shielded cables, and a voltage of 220 volts, will that meet the safety requirements?
If the methanol tank is a floating roof tank, the explosive hazard area is Zone 2； If the methanol tank is a dome tank and the explosive atmosphere is Zone 1, the cross-sectional area of the cable wiring shall be determined according to Table 5.4.1-1.
What is a cable used for? The instrument wires can be run through galvanized pipes in the cable tray to the control room.
The top is fixed; a fiberglass cable tray is used inside, and 2*1.5 shielded cables are employed to handle 220V voltage