Steam injectors

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Steam injectors

Post  lynnr on Sat 18 May 2013, 11:10 pm

Hi all

Over the test steamings and running about the house. I have been having issues with the steam injector not picking up or being teprimental. For last weekends event I removed the filter from the injector inlet and wow what a difference. The injector now picks up by simply opening the water full, turn on steam to almost any amount and the injector starts working, if below 100psi tweak the water flow back a bit to balance.

So I am thinking the gause on the filter is actually restricting the water flow. Has anyone else found this?

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Re: Steam injectors

Post  Tim Watson on Sun 19 May 2013, 12:28 am

Not had a problem with these filters on either Madeline or Frederick. Did you limit the Araldite on the seam? See if the filter lets water through easily on its own? I would definitely use a filter because debris will stop an injector from working.

Tim

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Re: Steam injectors

Post  highpressure on Sun 19 May 2013, 6:48 am

I also havent had an issue yet but the flow rate seems to have dropped off a little lately, having looked into the tender space recently it is quite dirty in there and I suspect the filter is getting clogged. I'll remove it and post a picture of it, give it a wash and fit it back in.

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Re: Steam injectors

Post  Flasback on Sun 19 May 2013, 12:33 pm

I have the the modified stem in the globe valve and the o ring keeps coming off and getting stuck in the filter. STW are now making a ptfe replacement as without the o ring the injector does not work and its a pain. I have also noticed if the engine is running too fast (regulator open) the water pump does not work correctly i.e. steam enters the pipe and it gets hot. If I run the pump with the regulator just open the pump works fine and the boiler fills up with water...may be its the lifter position, I have also replaced the SS balls in the check valves and replaced it with a rubber ones.

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Re: Steam injectors

Post  Tim Watson on Sun 19 May 2013, 12:40 pm

Sounds to me like you have too much lift on the check valve for the water pump, allowing the ball to bounce around too much rather than falling back onto the seat. Interested to see how long the nitrile(?) balls last.

Tim

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Re: Steam injectors

Post  highpressure on Sun 19 May 2013, 2:09 pm

Hi Tim,

I put nitrile balls in the first engine as it was always a pain to get them to seat and they kept letting steam back into the tender, don't know is they are still in there as its no longer mine but I believe they will degrade over time with the heat although not a great issue to change them. The new one does let back a bit but not enough to worry me to change them, but if I clean them out they seal better, but I suspect its more to do with how well they are seated in the first place. As far as I know I don't have a modified globe valve for the injector and its fine.

Kev.

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Re: Steam injectors

Post  Tim Watson on Mon 20 May 2013, 12:08 am

Other thoughts re: injectors being temperamental are that the feed water may be heating up in the belly tank over the course of a day, and may already be warmed if you used the lifter to load it on the engine. I am also wary of rally bowser water, which may be quite dirty, preferring to use drinking water.

Tim

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Re: Steam injectors

Post  Steam Traction World on Mon 20 May 2013, 12:28 am

DO NOT USE NITRILE BALLS ON THE CLACK VALVES BY THE BOILER Mad

They change shape over time and pressure pushes them in to the hole.

They can, however, be changed/used on the Water Pump but only after using the stainless steel one's supplied are used for a while so the seats wear a bit.

We've been there and done that....and if we wanted customers to use nitrile we would have supplied them.

Regards

Dean






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Seating your clack

Post  Steve Traill on Mon 20 May 2013, 6:12 am

It sounds like the seats are the problem not the balls, I've had no problems with them on the SC Burrell.
To seat mine properly I use an alluminium drift about 10mm x 100mm round bar. Place on the centre of the ball & give a good sharp tap with a hammer. Also check your ball is clean! As swarf can get around & cause problems.

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Re: Steam injectors

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