Executive standards:MT 558.1-2005 "Plastic Pipes for Underground Coal Mines Part 1: Polyethylene Pipes"

                    MT181-1988 "Safety Performance Inspection Specifications for Underground Plastic Pipes for Coal Mines"

Specification and model coverage:dn20-1000

Product introduction: The workshop is equipped with 10 production lines of Sichuan Jinshi Dongfang steel mesh reinforced polyethylene composite pipes. The nominal pressure of water supply, drainage, air pressure, and shotcrete pipes for underground coal mines is 0.4MPa~1.6 MPa. The maximum nominal pressure of gas drainage pipes is -0.097MPa.

Mining Indicator (MT558.1-2005)

Surface resistance

Depending on the use of the pipe, its surface resistance requirements are:

a) Pipes for water supply and drainage: the arithmetic mean value of the surface resistance of the outer wall should not be greater than 10x10°0

b) Positive pressure air duct: the arithmetic mean value of the surface resistance of the inner and outer walls should not be greater than 10x10

c) Gunite pipe: the arithmetic mean value of the surface resistance of the inner and outer walls should not be greater than 10x10°0

d) Negative pressure air duct: the arithmetic mean value of the surface resistance of the inner and outer walls should not be greater than 10x1060

e) Pipes for gas drainage: the arithmetic average of the surface resistance of the inner and outer walls should not be greater than 10x1060

Alcohol blowtorch combustion

The alcohol blowtorch burning requirements for pipes are as follows:

a) The arithmetic mean of the flaming burning time of the six samples should not be greater than 3s, and the flaming burning time of any one of the samples should not be greater than 10s;

b) The arithmetic mean of the flameless burning time of the six samples should not be greater than 20s, and the flamed burning time of any one of the samples should not be greater than 60s;

Nominal pressure and specifications of polyethylene pipes for underground coal mines (MT558.1-2005):