Sneyd Colliery Explosion 1942

01/01/1942 - Sneyd Colliery - Explosion / Coal Dust Explosion, Rail Haulage

I have come to the conclusion that six tubs were turned in at the top of the Banbury Crut Jig without any empty wagons being attached to the other rope. From some unknown cause the loads at the top of the jig ran away and as these six loads careered down the jig, the oncoming rope possibly got behind one of the wheels. When the impact occurred at the pass-by it would have been responsible for pulling the jig wheel out at the same time breaking the rope. If the tubs were not already derailed this would derail them. A pair of glands covering a half inch square hole in the compressed air main was knocked down the pipes a matter of 6 inches. The escape of compressed air at 18 lbs. per square inch pressure would increase the amount of turbulence already set up by the runaway tubs. Immediately following this, the tubs got rucked up and damaged the power cable, the resulting cloud of dust produced by the rucking of these tubs, due to the force that had been thrown out into the jig, would travel back up the jig, being assisted in doing so by the ventilation which is travelling at 200 feet per minute and when it had almost gone, the finer particles, which were still in an agitated state, due to the turbulence of the compressed air pipe, were, I feel sure, ignited by one of the following causes:-

  1. "Frictional sparks from the tubs crossing the compressed air main and steel arches at the time when they were rucking up and also from sparks produced from the wheels and the breaking rope.
  2. Electrostatic sparks from the discharged compressed air.
  3. Spontaneous electrification of the dust cloud, I feel sure, played some part in making this dust cloud more easily ignited than in normal circumstances.
  4. The cable, and I have gone into this very fully with people who know a lot more about cables than I do myself, was concerned but I have to come to the conclusion that the cable was not responsible.”

After hearing all the evidence, Sir Henry Walker came to the following conclusions-

1). That the up-going rope got over the inside wheel of the first tub of the set
coming down at the time of a runaway
2). The marks between the strands of the sample of rope examined by Mr. Clelland were made by the rope rubbing against the front right-hand corner of the first tub coming down and that the two small flakes of mild steel he found embedded in the rope came from the bottom of this tub.
3). That the capel of the up-going rope was caught against the sole of this tub and so pulled off, the jig-wheel being pulled down and the set derailed at the same time.
4). That 3) occurred when the first tub on the down coming set was about ten feet
above the cock in the air main.
5). That, thereafter, the derailed tub or tubs displaced the cock and then damaged the electric cable. And I think
a). The dust which was ignited was dust from the jig and not from the runaway tubs
b). That such dust had been ignited before either the hole in the air main had been exposed or the electric cable damaged.
c). That the ignition of such dust was due to heat generated by friction between the up-going rope and the underside of the first down-coming tub of the runaway set.”