Bending tube.

[Ton-up]

I'm helping a mate to rebuild a 1916 steam engine loco. We need to find someone to bend some now pipework as in the picture.
The original pipework is approx.70mm dia. and 4mm thick.
Got in touch with a couple of people and they can't do bends closer than 200mm.
As you can see, it's bends are close and very twisted!
Don't want it fabricated.
Anyone know any companies that could bend this.
Thanks.

 

[addjunkie]

That looks to me like it has been hand formed hot and packed with sand. When cherry red bent around a pair of spikes, then cut to length.

No youd probably be looking for someone with cnc mandrel bender.

 

[magnet]

H.A McEwen Boilermakers

Heritage and Industrial Steam Boiler Services from H.A. McEwen Boiler Repairs Ltd. Based in Yorkshire, we operate in UK and Ireland providing Specialist Industrial Boiler Repairs and Rebuilds for all types of Modern and Vintage Steam Boilers

mcbo.co.uk

 

[Morrisman]

That looks to me like it has been hand formed hot and packed with sand. When cherry red bent around a pair of spikes, then cut to length.

No youd probably be looking for someone with cnc mandrel bender.

I saw a video of a CNC tube bender where the tube came out a nozzle, somehow bent as it left. It was amazing, no end of twists and curves, all programmed in beforehand.

Similar to this. ETA: found it.

 

[Erie Fred]

I saw a video of a CNC tube bender where the tube came out a nozzle, somehow bent as it left. It was amazing, no end of twists and curves, all programmed in beforehand.

Similar to this. ETA: found it.

There is a bushing that is a slip fit on the tube/pipe.
The OD of the bushing is a ball, the black flat thing under it is an X-Y slide.

 

[Morrisman]

There is a bushing that is a slip fit on the tube/pipe.
The OD of the bushing is a ball, the black flat thing under it is an X-Y slide.

I saw a longer video a few years back, pumping out complete complex exhaust pipes, front to rear, in one piece, literally in seconds per length. Probably not practical for a one off, but if someone was quick with their programming it might be easy enough.

 

[Ian X]

Babcock, or back then Ames Crosta Babcock had a monster version of that machine in one of the yard sheds at Rosyth, it was used for off site contracts, probably for BNFL work. Not once did I see it in operation.

 

[graffian]

Try exhaust makers.
Specialised Exhausts in Mitcham used to sand bend tubes.
I saw a car there having a set of headers made, nest of snakes in the V sort of headers.
I would have thought there were other people doing the same sort of thing.

Have a try at sand bending.
I would have thought that part wasn't to hard to do, I found header tubes harder to do than thicker wall tubes.

 

[oldbikedavey]

Ben Hardman is pretty good at tube bending by the packed sand method.
Up around Wigan way, or thereabouts.....

 

[Robotstar5]

You could try SVR engineering services or Tyseley locomotive works.

 

[Ton-up]

Thanks for the suggestions

 

[seanc]

if your looking for someone to do it in 4mm pipe then that could also be an issue, cant imagine thats run of the mill for most pipe benders

 

[gaz1]

i will give you the old method of hot forming tube

 

[addjunkie]

i will give you the old method of hot forming tube

Cant see that working with a 70mm dia tube with a 4mm wall. But as its steam and old I suggest the tube will be imperial, my first guess from the wall thickness would be sched 40. Assuming its a relatively low pressure wet steam system. Remember as its a steam engine that will origionally have been made by a very skilled boiler maker or blacksmith.

The way I was taught many years ago to do odd bends like that, before cnc etc. would be build a jig for the two flanges, so you know you have not lost your bolt hole dimensions/ locations. Cut off flanges and clean up ready to accept new pipe, or make new.
Get a piece of tube too long, pack it with dry silver sand. Heat the tube cherry red, over a fair length and work between two fixed bars to gradually pull into the required shape, re heat as required. Once happy trim to length, and re weld in your jig to the flanges. Pressure test to 150% of MAWP.