# Edwards Air Pumps



## japottinger (Jun 16, 2004)

As I recall the air pump which was driven by levers off the fore end of our steam recip. engine on SS Mahar to maintain the vacuum was commonly known as the Edwards pump.
I read this week that the long established company ( 1914 or18)has been bought by Atlas Copco. They have been recently manufacturing high tech vacuum pumps.
As an aside another long established UK company is sold overseas, shareholders will do anything for a fast buck it seems nowadays, plus zillions for those dealers handling the sale.


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## Derek Roger (Feb 19, 2005)

On newer steam plant the Edwards air pumps were replaced by air ejectors which was simply steam passing through a venturi nozzle . No moving parts and more efficient .

Cheers Derek


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## chadburn (Jun 2, 2008)

Pump and Rams packing from memory was a turn of Serpent C followed by a turn of Greasy Hemp until the gland was packed.


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## oglebilluk (Mar 14, 2006)

Interesting reminder because on Brocklebanks Malancha the air pump, powered by a single cylinder vertical Weirs steam engine was alongside the control platform. With a wooden pole attached to the crosshead so the watchkeeper could see that it was still operating and pumping into an open hotwell

Bill




japottinger said:


> As I recall the air pump which was driven by levers off the fore end of our steam recip. engine on SS Mahar to maintain the vacuum was commonly known as the Edwards pump.
> I read this week that the long established company ( 1914 or18)has been bought by Atlas Copco. They have been recently manufacturing high tech vacuum pumps.
> As an aside another long established UK company is sold overseas, shareholders will do anything for a fast buck it seems nowadays, plus zillions for those dealers handling the sale.


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## Duncan112 (Dec 28, 2006)

Whilst Edwards were owned by BOC they took over the last vestiges of the Bolton engineering company Hick Hargreaves and still maintain a small design office near the Reebok stadium (On the old DeHavilland propeller plant site, but that's another story) - the Bolton office deals with air ejectors which I occasionally get asked to inspect - the manufacture is all outsourced now - attached is a photo of one of these in the final stages of assembly. Surprisingly no steam test is carried out as the design is so well proven, merely visual, hydrostatic and radiographic inspection.


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## jamesgpobog (Feb 18, 2012)

Reminds me of the bilge eductor that Mispillion had...


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## japottinger (Jun 16, 2004)

Duncan112 said:


> Whilst Edwards were owned by BOC they took over the last vestiges of the Bolton engineering company Hick Hargreaves and still maintain a small design office near the Reebok stadium (On the old DeHavilland propeller plant site, but that's another story) - the Bolton office deals with air ejectors which I occasionally get asked to inspect - the manufacture is all outsourced now - attached is a photo of one of these in the final stages of assembly. Surprisingly no steam test is carried out as the design is so well proven, merely visual, hydrostatic and radiographic inspection.


Beautiful welds, were they sub arc?


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## Duncan112 (Dec 28, 2006)

I think so - I was supposed to see the pre weld set up but the project got delayed and then was welded without witness so I didn't see the process and don't have a copy of the procedure to hand. Two brothers do the welding and, as you say it is to a very high standard (as would be expected for pressure containing parts). Company in Bolton called Velden Engineering.


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## japottinger (Jun 16, 2004)

Re Edwards air pumps. The 2nd Engineer Officer on SS Maihar voyage 94 and Chief next trip was Jack Evans from Liverpool. He had joined Brocklebank from Harrisons ostensibly because Harrison had stopped their Calcutta run and he reputably had a "friend" in Calcutta, so this was a means of transport to there. He related a tale of being on Harrison's Tribesman when the ar---e blew out of the bottom of the recip air pump, driven by a lever from HP con rod. He says, they chain riveted in the all in one missing piece into the bottom of the pump by a series of drilled and then tapped interlocking holes with fitted screwed rods to effect a repair. He swears by it so have to believe him. In passing he was ever referred out of earshot as "chain rivet Jack!"


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## chadburn (Jun 2, 2008)

I have been involved in a similiar operation on an up and over sea valve cover (in situ) which cracked (no met-lok in those days). It takes careful measuring on the template/ drill guideplate and even more careful drilling especially when you are drilling in such close proximity to the previously drilled holes on either side. What we did was to drill and tap the two ends of the crack and bolted the guide plate over the crack and then drilled every other hole, then the ones between. Quite a job to do it with the bottom of an Edwards air pump. You know yourself J.A when there is no alternative it has to be tried. As the old saying goes "Better to have tried and failed than never to have tried at all"


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## teop (Jan 13, 2008)

Just to add, that Metalock Co sewed -in the fifties? a bottom cover piece on an Edwards dir.dr. ap (attached to aft ,LP) on the stbd triple.
It worked well to the bitter end- ship scrapped 1968.
Classical-forgetting to open valve prior to starting engine. comunication fault, Eng./Oiler.
regards
teop


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