Safety Valves

Safety Valves

This topic has 9 replies, 4 voices, and was last updated 4 March 2014 at 09:59 by Deltic007.

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2 March 2014 at 16:47 #7059
Deltic007
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@deltic007
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2 March 2014 at 16:47 #145728
Deltic007
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@deltic007
Hi all

I am changing the safety valve on my 3 1/2 lilla locomotive from the sprung cartridge arm type,question is what is recommended for a boiler on a 3 1/2g loco to give enough pressure drop and what particular type is best suited.

Or do i need 2 valves?

Thanks
2 March 2014 at 21:41 #145762
nigel jones 5
Participant
@nigeljones5
Off the top of my head (which is what I build to!) a 3/16 hole with a 1/4 ball and spring will be more than plenty.
2 March 2014 at 22:05 #145765
Deltic007
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@deltic007
Thanks Fizz
3 March 2014 at 00:11 #145782
nigel jones 5
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@nigeljones5
Infact possibly very excessive! This would be better suited to a 5" scale, down size!
3 March 2014 at 09:03 #145797
Steambuff
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@steambuff
Fizzy,

Remember that the 3 1/2" Lilla is as big as some 5" loco's (If not bigger, due to it being a narrow gauge loco)

Dave

.
3 March 2014 at 23:00 #145897
julian atkins
Participant
@julianatkins58923
hi deltic,

can recommend you look at Polly online catalogue and choose a suitable Gordon Smith safety valve and spring and drawings etc.

far superior than anything else and will easily satisfy the 'accumulation' test.

cheers,

julian
4 March 2014 at 06:58 #145910
Deltic007
Participant
@deltic007
Yes I have seen the Polly ones

question is which one is suitable??
4 March 2014 at 08:47 #145923
julian atkins
Participant
@julianatkins58923
i would suggest SV#4

i have no connection with Polly other than being a satisfied customer

cheers,

julian
4 March 2014 at 09:59 #145935
Deltic007
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@deltic007
Thanks julian
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