1. Characteristics of product:
Explosion-proof fire breathing valve has two functions with explosion-proof flame arrestor and breather valve. Kill two birds with one stone, safe and convenient. Explosion-proof fire breathing valve comply with SY/T0511-1996 standards and is divided into common type and all-weather type two series and A, B, C three operating pressure: A: -295pa +355pa, B: -295pa +980pa, C: -295pa +1765pa; fire breathing valve products meet the national standard GB5908-2004 performance to the oil tank fire resistance requirements. Through the Scientific Research Institute of the Ministry of public security fire on the fire retardant core of qualified test 13 detonation and burn a hour.

2. Ordering instruction:
2.1 Please indicate the order products are all-weather type (Q) or ordinary type (P) according to product specification statements, and indicate the pressure level and specifications of the products.

2.2 The valve key part of products made of polytetrafluoroethylene material. When using, positive and negative pressure valve can not open at the same time. Therefore, in the storage and transportation, the installation should avoid products will be inverted and the violent collision.

2.3 Every six months to product positive, negative valve sliding properties and the fire retardant core to conduct a clean-up cleaning and inspection. Open the normal and fire resistance performance to ensure.

3. Technical parameters:

Nominal diameter	Outer diameter of flange D1	Distance between flange holes D1	Working pressure Mpa	Material
DN40	f130	f100	0.6-2.5	Cast iron, cast steel, aluminum alloy
DN50	f140	f110	0.6-2.5	Cast iron, cast steel, aluminum alloy
DN80	f185	f150	0.6-2.5	Cast iron, cast steel, aluminum alloy
DN100	f205	f170	0.6-2.5	Cast iron, cast steel, aluminum alloy
DN150	f260	f225	0.6-2.5	Cast iron, cast steel, aluminum alloy
DN200	f315	f280	0.6-2.5	Cast iron, cast steel, aluminum alloy
DN250	f335	f335	0.6-2.5	Cast iron, cast steel, aluminum alloy