MT 378-1995 in English

Technical background of the standard

This standard was issued in 1995, when coal mine safety accidents were prevalent. It is a special test method developed for accidental explosions of explosives during underground blasting operations. The steel white gun was used to simulate the closed environment underground, filling the technical gap in the safety performance evaluation of domestic coal mine explosives at that time.

Analysis of core terms

Deflagration resistance: refers to the ability of explosives to resist the transition from detonation to combustion under high temperature and high pressure. The standard uses the observation of whether the full combustion phenomenon (only salt cake remains) occurs in the explosive volume as the basis for judgment.

Key parameters of the test device

Key points of the test process

1. Preparation of explosive rolls: divided into two processes: powdered explosives (filling sulfuric acid paper tubes) and water-containing explosives (ignition of black powder)
2. Environmental control: test temperature 20-30℃, water content of explosives <0.5%
3. Sealing requirements: front and rear sealing plugs need to be tightened with a wrench, the test is invalid if leakage occurs

Judgment rule implementation case

One mining emulsion explosive fully burned out in 10 consecutive tests:
1. 10 additional retests as required by the standard
2. No full combustion occurred in the retest → judged as qualified
3. If one full combustion occurred in the retest → directly judged as unqualified

Comparison of standard evolution

Suggestions for on-site implementation

• Regularly check the dimensional tolerance of steel white gun, paying special attention to the wear of the bore diameter
• The No. 2 water-resistant explosive of the main explosive volume must comply with the component requirements of GB 12437
• After the test, you must wait 2 minutes before opening the sealing plug to prevent residual gas from igniting and exploding