Rotative Pumps


Horizontal Rotative Boiler Feed Pump.

Horizontal Rotative Boiler Feed PumpThis pump is copied from a design that was once produced by Hawthorne Davey & Co. Ltd. of Leeds.   Like Robeys of Lincoln, they also used bars to tie the steam and water cylinders together.   As far as we are concerned this makes it much easier to machine each casting.   Due to the size and weight of the flywheels, the speed of not much below 60rpm, excludes it from some applications.   However a by-pass can be fitted to control the water into the boiler.

As in the prototype, the flywheels are only used to enable the pump to carry over the dead centres at the end of each stroke, therefore unlike the other pumps we supply, this one is not self starting if it has come to rest on the dead centres.   One slide valve is used for the steam cylinder which is operated by the usual eccentric on the crankshaft.

An alternative to the pump shown in the photograph, is one that uses a scotch crank.   This is easier to make and also reduces the overall length by 1½”.   This is shown in the drawings.

As the pump is double acting, four valves in the form of stainless balls, are required in the water end and are installed at the side of the cylinder.

Items supplied:-

9 GM castings,  Material for pistons,  2 iron flywheels,  O-rings,  4 – 6BA allen grub screws,

3 sheets of drawings, – sheet 1 is the assembly with all parts itemised plus a parts list, the other 2 sheets contain the parts that require making.

 

Approximate weight built up 5lbs Overall Length 9¾”
Steam cylinder 1″ dia Scotch Crank Version 8¼”
Water cylinder 5/8″ dia Width over Flywheels 4”
Stroke 1¼”