Rootes blowers.....pit ventilation

[inbye]

Does anyone have experience of pits using Rootes type blowers, for ventilation. I know they were an accepted form (if unusual) of ventilation fans, in collieries, did anyone have actual experience of them?

For anyone who hasn't a clue what one is, you can often find a much smaller version fitted to vintage sports/racing cars, as a supercharger.

[dazbt]

Jun 23, 2011 13:56:41 GMT -5 inbye said:

Does anyone have experience of pits using Rootes type blowers, for ventilation. I know they were an accepted form (if unusual) of ventilation fans, in collieries, did anyone have actual experience of them?

For anyone who hasn't a clue what one is, you can often find a much smaller version fitted to vintage sports/racing cars, as a supercharger.

I don't know anything about the Rootes blower but I do remember the 'Druk Claxon' being used on shearers and trepanners, the same 'blower warning device' that was used on vintage motors;

[shropshirebloke]

All I can say is that given the need for ventilation to be as reliable as possible the added complexity of the Roots Blower (two closely meshing rotors) sounds distinctly hazardous compared with a simple fan.

These days I work as a printer, and we depend on large volumes of relatively low-pressure air and vacuum to move paper through the machines - the claw. or Roots type blowers are considered to be more efficient but less reliable than the traditional single element types.

[John]

Never heard of a Rootes blower. I've seen venturie(sp) air diluters used underground.

And Daz, seen the Klaxons with small FLP motors for use in hazardous zones, ran off 110 volts.

[shropshirebloke]

Here's something on the Roots Blower John: en.wikipedia.org/wiki/Roots_type_supercharger

The venturi type just ran on compressed air (similar principle to a spray gun) - theoretically safe except for the risk of generating static electric sparking, but that was inevitable with any compressed air device.

[dazbt]

The venturi system of 'blowing' or 'vacuuming' was used on shearers and other cutting machines both as a means of atomising water as a dust suppressant and as a means of introducing an air flow to dilute potential methane accumulation within or around the cutting element. These systems used water flow, one type being a simple venturi unit mounted on the body of the machine whilst another more complex system drew goaf-side air through hollow cutting element drive shafts and distributed relatively large volumes of air and atomised water to the face side cutting area.

[John]

Jun 24, 2011 1:21:37 GMT -5 dazbt said:

The venturi system of 'blowing' or 'vacuuming' was used on shearers and other cutting machines both as a means of atomising water as a dust suppressant and as a means of introducing an air flow to dilute potential methane accumulation within or around the cutting element. These systems used water flow, one type being a simple venturi unit mounted on the body of the machine whilst another more complex system drew goaf-side air through hollow cutting element drive shafts and distributed relatively large volumes of air and atomised water to the face side cutting area.

BG used them on the exhausts of diesel engines underground to dilute the exhaust gasses Daz, the big V8 Scooptrams had two. As they have no flammable gasses they don't need scrubbers and flame traps.

[inbye]

Mmmm, what I should have done was read my reference, before asking the question.
The reason nobody has come across one, is only one (British) colliery was equipped with one. Chilton colliery, of the South Durham coal co, had one in 1877. The ventilator comprised of two contra-rotating lobes, each one 25 feet in diameter & 13 feet in length. The tolerance between the rotating lobes & the housing was "not more than 1/8 of an inch".

At 12 rpm the cfm was 67,312 & at 21 rpm it was 118,272. Must have been an impressive sight at whatever speed.

Sorry if I started a bit of a wild goose chase...