Piston complete
- Made:
- c.1874
Piston with metallic packing
In this packing there are two split piston rings of L section, expanded radially, and separated longitudinally by about three turns of a single helical spring. The method of construction of this internal spring was patented in 1874 by Messrs. E. Wigzell, J. Pollit and W. Mellor, and consists in tapering a bar of spring steel to the required shape, winding it on a revolving mandrel, and tempering it in oil. A larger example of this spring is also shown, together with the clamp used to hold the rings while getting the piston into the cylinder.
