DJB Automatic drain cocks
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Whosk
DJB Automatic drain cocks
Has anybody had experience at fitting these drain cocks to a Ragleth or Egrid? is it hard, is it worth it, do they work?
The initial run and clearing the condensate is quite unsatisfactory and unprototypical to my mind, besides looking like a goose trying to get it to run backwards and forwards while others/public are watching.
I have minimised the problem with technique , ie, run a bit less water at the start and letting the steam blow well before shutting the blowdown valve. They seem like they might be the next best step-providing they work!
Wayne
The initial run and clearing the condensate is quite unsatisfactory and unprototypical to my mind, besides looking like a goose trying to get it to run backwards and forwards while others/public are watching.
I have minimised the problem with technique , ie, run a bit less water at the start and letting the steam blow well before shutting the blowdown valve. They seem like they might be the next best step-providing they work!
Wayne
- AFGadd
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I've fitted these cocks to a couple of Accucraft engines and in my opinion they do work.
Fitting is, I believe best done by removing the cylinders and using a small pillar drill to cut the holes.
I found the easiest method to remove the cylinders was to remove the body & boiler as well.
However, I didn't find the job difficult or daunting but the job does take thought.
The rewards were certainly worth the effort.


Fitting is, I believe best done by removing the cylinders and using a small pillar drill to cut the holes.
I found the easiest method to remove the cylinders was to remove the body & boiler as well.
However, I didn't find the job difficult or daunting but the job does take thought.
The rewards were certainly worth the effort.


- tom_tom_go
- Driver

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- AFGadd
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- Joined: Sun Apr 17, 2011 6:31 pm
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Big Jim
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LnBmad
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steam4ian
There is a lot of discussion about these valves in the ride behind gauges as well.
As LnBmad says they consist of a ball bearing in a chamber which can at some point seal off the outlet. Operation relies on the interrelationship between the size of the entry port from the cylinder, the chamber containing the ball and the exit port. I think that if the entry port is smaller than the exit port they will work because condensate does not expand. The condensate velocity into the valve is more than that leaving the valve and the ball is not driven to the exit port. However steam will expand and its velocity will lift the ball to seal the exit port.
One problem I see with ride behind gauges is that they can't relieve priming where hydraulic lock up means a rod will get bent or worse.
As LnBmad says they consist of a ball bearing in a chamber which can at some point seal off the outlet. Operation relies on the interrelationship between the size of the entry port from the cylinder, the chamber containing the ball and the exit port. I think that if the entry port is smaller than the exit port they will work because condensate does not expand. The condensate velocity into the valve is more than that leaving the valve and the ball is not driven to the exit port. However steam will expand and its velocity will lift the ball to seal the exit port.
One problem I see with ride behind gauges is that they can't relieve priming where hydraulic lock up means a rod will get bent or worse.
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