PTA / Stelliting

PTA (plasma transferred arc welding) & Stellite hard facing

The inclusion of a Hettiger 6 axis Plasma Transfer Arc (PTA) machine & tempering furnaces allows R.L. Hill Engineering to manufacture & fully control all processes involved in the manufacture of high temperature steam valve stems, seats & related products. PTA is used to deposit the hardfacing material & unlike other surfacing processes, PTA creates a full metallurgical bond with the parent material. Pre & post heats are accurately controlled with our furnace facilities. Both furnaces are linked to our server and data is continually recorded while in use. We can supply full heat treatment record graphs showing temperature over time for all our furnace processes.


Because of our extensive stocks of parent materials & our PTA facility we can manufacture new valve components in very short lead times. This is a major advantage when the need to replace valve components is not found until you’re in the thick of a shutdown.

Kennametal Stellite 6®

Most high temperature valve seats are manufactured from Stellite 6®. Stellite 6® is also used to coat the wear areas of the valve stem. R.L. Hill Engineering specifically uses Kennametal Stellite 6® consumables with our PTA systems. Other grades of Stellite® powder are also stocked as well as tungsten carbides, inconels, martensitic & austenitic stainless steels.

Stellite 6® – Kennametal Stellite

Solid Stellite Bushes

To complement the manufacture of our high temperature steam valve spindles & seats we also supply fully machined solid Stellite bushes. Again these bushes can be produced in surprisingly rapid lead times. A lot of sites are seeing the benefits of our solid stellite bushes over conventional nitride hardened or even stellite coated bushes. There is no chance of a coating cracking and these bushes are much more economical to refurbish down the track, numerous times over.