Explosion protection types and principles for non electrical equipment:

Structural safety type c

The principle of structural safety is to select equipment types that do not contain ignition sources under normal working conditions, and then apply reasonable engineering principles to reduce the risk of mechanical failure causing ignition temperature or sparks to a very low level. Typical solutions include: installing filters on the air compressor to prevent dust from entering the compression chamber; Using carbonization resistant lubricating oil ensures that carbon deposits do not occur inside the air compressor during operation due to the high temperature of the lubricating oil, thereby preventing combustion and explosion accidents in the air compressor.

Control ignition source type b

The principle of controlling the ignition source type is to add sensors to the equipment to detect impending hazardous conditions, and initiate control measures in the early stages of condition deterioration before the potential ignition source transforms into a limited ignition source. A typical solution is to use protective devices such as pressure reducing valves, fuse plugs, and temperature regulating valves. When the equipment experiences abnormal working conditions and the pressure or temperature has not yet reached the dangerous pressure or ignition temperature, measures should be taken in advance, such as releasing pressure, cutting off the connection between the device and the power source, disconnecting the power supply, etc., to prevent potential ignition sources from causing explosion hazards.

Liquid immersion type k

The principle of liquid immersion type is to immerse the potential ignition source in the protective liquid, or to continuously cover them with a flowing film formed by the protective liquid, making the potential ignition ineffective. The protective liquid can be the actual process liquid itself. Typical solutions include oil filled gearboxes; A disc brake immersed in oil can not only cool down the gears or brake, but also extinguish sparks generated by gear collisions, thereby preventing explosions.

Explosion proof certification standards for non electrical equipment:

GBT 3836.1-2021 Explosive Atmospheres Part 1: General Requirements for Equipment

GBT 3836.28-2021 Explosive Atmospheres Part 28: Basic Methods and Requirements for Non Electrical Equipment Used in Explosive Atmospheres

GBT 3836.29-2021 Explosive Atmospheres Part 29: Non electrical equipment structures for explosive environments Safety type "c", controlled ignition source type "b", liquid immersion type "k"

Explosion proof marking for non electrical equipment:
Ex h, regardless of the type of explosion-proof protection adopted for non electrical equipment, the explosion-proof symbol is uniformly written as "h", which is different from the explosion-proof symbol of electrical explosion-proof equipment