British pipe threads on water pump ?

[bcarwell]

I just got a trash pump with 3" input and output ports. I think I now know why I got such a good deal on it. It appears the threads per inch (TPI) is about 11. I looked up on a thread chart and British Standard Pipe both parallel and tapered (BSPP and BSPT) is.... 11 TPI, not close to the 8 for NPT or 6 for NST(NH).

So..., assuming I'm correct, does anyone know where I could find adapters and or reducers and hoses for BSP threading- Canada ? And would it be "pipe" dreaming to think I could find an adapter or reducer to go from BSP to NPT or NST so I could use American standard hoses from Tractor Supply, etc.

Otherwise, could I use hose clamps cinched down tight on press fit hose around the male input and output ports ? Will they hold a nominal 60 GPM and 60 PSI on the output side (I was planning on reducing the 3" output port to 2" or even 1 1/2 inches to make the hose more manageable for some small pasture pile burns. I know all about cavitation and back pressure injuring impellers, etc., etc. but was going to use it only for short periods to wet down, etc. and not for prolonged periods, and was also possibly going to recycle some of the pressure/flow back into the reservoir tank to minimize any problems.

Bob

 

[schmism]

the inlet and output threads are cut directly into the housings?

It might be easyer in the long run to tig a new fitting onto the end of the existing houseing. (like a cam lock fitting)

 

[bcarwell]

Thanks for the reply Steve. The input and output ports are bolted on flanges with gaskets, so I guess if all else fails I can maybe find replacements with the right threads (it is an Apache attempt at a Honda trash pump knock off so if I got REAL lucky the flanges would interchange but probably cost too much) or maybe weld up replacements. There is a guy on Ebay selling a BSP female to camlock 3" adapter right now that I might try. I assume that epoxying on a fitting wouldn't work (to try first if I'm going to end up trashing the existing ports anyway) ?

Bob

 

[schmism]

I assume that epoxying on a fitting wouldn't work (to try first if I'm going to end up trashing the existing ports anyway) ?

remember cross threads hold better than locktight

A quick google search of 3" trash pumps showed both kinds of pumps with bolt on flanges and threads cut directly onto pump bodies.

I suppose it call comes down to the time and trouble involved. It may be the least amount of hastle to go to the local farm supply store and pick up a cam lock fitting and take it to the nearest machine shop and have it tigged on for a few bucks

else you add some silicone to the threads then try to force a 3" camlock NPT onto fitting. cross threading as you go. Another option if your considering bugger'n up the existing flange....

you could take the flange off and take it to a local pump place and see if they have a replacement of the right type....

the nice thing about all these options as opposed to ebay/internet is you can take the part in person and look at it and compair it to fittings you have in your hand to make shure things work.

 

[Kays Supply]

Have you tried a female fire hose fitting on your pump. One of the trash pumps I have has male threads that a fire hose female fits.

 

[bcarwell]

Fire hose threading unless I'm mistaken for 3 inch hose is NST (aka NH) 6 threads per inch, but as I noted my male 3 inch fitting on the pump is the British 11 threads per inch.

BTW the pump looks to be most likely cast iron (or less likely aluminum I guess) and I would assume it would be a booger to weld.

I have the hose nuts that screw onto the male fittings if I could just find 3 inch hose with a flange or flair at the end. Then I could thread it through the nut and put a gasket on the male fitting on the pump and screw the nut down so I that it compressed the flange or flair on the hose against the gasket and the pump wall to seal it in a compression fit. Then I could make up the other end of the 3 inch hose as desired with whatever more standard fitting I wanted.

Anyone know where to find such a 3 inch suction and discharge hose with a flange on the end ?

Bob