In a message dated 12/1/2005 8:04:41 A.M. Pacific Standard Time, [EMAIL PROTECTED] writes: I have successfully used a tiny "wobbler" in a lubricator but there, of course, it is itself surrounded by lubricant. As a water pump, there might be a problem with lubrication as the faces would need to be held in contact with rather more than boiler pressure to prevent leakage.
Yes, LBSC in his designs used a wobbler as a cylinder oil pump, and I have used a wobbler as an air compressor (low pressure, aquarium bubbler) But, normally we think of gas (air or steam) not in-compressible fluids with wobblers. The problem is that on most wobbler designs there is part of the cycle where both ports are blocked and with a liquid working fluid there would be lock up or forcing the cylinder away from the valve face. The conventional "ram" type pump can be driven by an eccentric and I don't think it would make much difference in our small scales if the inlet and discharge valves were not right on the cylinder body so a check in the tender and the normal check valve at the boiler feed point might be enough to work on our scale. Just have to arrange things so that the pump is always flooded with water or a ram pump can work against a slug of air just compressing and releasing the same air over and over and never pumping liquid. I would hate to try to build an injector for the smaller scales (Probably since I never got one at 3/4 inch to the foot to work very well) I don't know what the problem is exactly, but I have seen boiler feed ram type pumps driven from the cross head as well as axle driven pumps. _______________________________________________ SSLiveSteam mailing list Send messages: [email protected] Cancel subscription: http://postfix.45mm.com/mailman/listinfo/sslivesteam Rules: http://www.45mm.com/sslivesteam_guide.html
