winson 1400 steam pipes

[davey]

Hi
I am at the stage ready to connect up some pipes, my winson ( early first batch i think) instructions say the hand pump goes to the top boiler clack, but on later models it looks like the hand pump goes to the bottom left backhead clack. At my local model engineering club it has been suggested to connect the injector to the top boiler clack and the hand pump and axle pump to the bottom backhead clacks. Any ideas?
thanks in advance
Dave

[Jason]

Dave,

With experience I find that injectors always perform better feeding to a clack high on the boiler rather than low down, I think this is due to forcing water into the steam filled section of a boiler is easier due to lower pressure rather than the water filled section, perhaps another member can answers this for us and explain the science?!?!

For axle and hand pumps they perform fine on the bottom clacks.

Hope this helps.

Jason

[pault]

Hi All
Personally I do not like the idea of feeding stone cold water through backhead clacks were within a very short distance the cold water comes into contact with the rather warmer inner fire box. The obvious exception to this is where they feed in above the crown and have internal pipes which take the water further forward into the barrel. If you feed the pump water in through a top feed it is warmed by the steam and then mixed with the water before coming into contact with any metal.
As far as which works best in my experience as far as working goes it makes no difference if you use top feed, bottom feed, or back head feed. They are all feeding against the same pressure. However when things go wrong there is an argument for putting the injectors on the top feed. If a clack for an injector, on a top feed sticks up you loose steam at a fair rate but it’s not usually difficult to deal with as you have a bit of time in hand. If however a clack below the water line (which most backhead clacks are) sticks up then you start to empty the boiler of water at quite a fast rate which can mean dropping the fire PDQ. If however the clack is being feed from a pump the pump has its own valves to prevent water flowing out of the boiler, and the pump will in all likelihood continue to feed the boiler. At worst when the bypass is open it will feed into the tank, but it is a manageable problem.
Regards
Paul