Question: Air brake components

[utt61]

I have recently had to remove the footbrake valve from my 1961 ex-RoF Iron Fairy crane for servicing, and although the valve is now ready to refit I had a problem removing it from the pipework which will entail replacing some of the piping.

 

The valve, and indeed all the other air brake parts, are standard Clayton Dewandre of the period (the valve is a "D-1" valve), and the pipes are 5/8" od steel with fittings that are similar in someways to plumbing compression fittings - there is an "olive" round the outside of the pipe and a nut which compresses the olive when tightened.

 

On the pipe to the front brake actuators and the pipe to the rear actuators, the nut had seized onto the pipe with the result that the pipe has twisted and become deformed.

 

I have never replaced components on an old air brake system before and have no idea how unusual and/or difficult to obtain suitable pipe and fittings are likely to be. Can anyone more informed tell me where I might be able to get suitable parts, preferably in the Dorset (Poole) general area?

 

Very many thanks in advance; I know someone here will be able to advise!

[TooTallMike]

I've just purchased 3/8" and 1/2" pipe and olives from Ebay for the brakes on my Autocar project. If you want to buy from a shop, try looking for air conditioning suppliers as they can supply pressure-tested pipe.

 

- MG

[cosrec]

If the steel pipes have olives fitted and not flared ends as far as i am aware it is perfectly acceptable to replace with nylon pipe and olives saving a lot of grief bending shaping steel replacements although i depends on how much of a purist you are. Just clean up the original nuts and use. One exception the first steel pipe after the compressor should be retained as it gets very hot. Nylon pipes and olives very easy to obtain from local HGV motor factors.

[cosrec]

Quite by chance after I wrote post I went to local factors in Goole for some pipe and olives for Foden cost £26 including vat for 30 m *12mm pipe + pack 10 olives to suit. Yes they do imperial up to 3/4

[utt61]

Gents, thank you both for this info, especially the plastic suggestion. The pipe from the valve to the front (non-steering) axle has multiple bends and plastic would be much easier to fit.

 

Fortunately the pipes from compressor to receiver and receiver to valve are all ok.

[Sean N]

Poole area, try for dedicated CV factors Parsons Parts in Francis Rd, Wallisdown or Commercial Components at Dawkins Rd, or alternatively for suitable pipe and fittings try Thread and Pipe on the East Howe industrial estate. Alternatively a bearing and power transmission factors such as Industrial Links in Upton or Brammer on the Nuffield estate should be able to help, but won't have the range of pipe & fittings off the shelf.

 

If you're using plastic pipe with olives and nuts you'll normally need ferrules (inserts) to stop the pipe collapsing as you tighten the nut.

 

Nuts freezing to the pipe is quite common with old pipes; when dismantling air, vacuum or brake pipe I normally coat liberally with penetrating oil, leave to free up and then if it feels tight work the nut back and forth over about an eighth to a quarter of a turn before undoing to make sure it's free. You need to check the pipe carefully anyway after removal though to make sure it isn't dangerously pitted / corroded.