The flight is the most strained element of a screw. That is why murex offers you highly effective hard-facings against wear and corrosion.

Several types of hard-facings are available:

Hard-facing Base alloy Hardness Thickness Flight width embeded
Stellite 6 Cobalt HRC 38–42 2.0mm–2.5mm min. 2mm yes / no
Stellite 12 Cobalt HRC 43–49 2.0mm–2.5mm min. 5mm yes / no
Colmonoy 56 Nickel HRC 52–56 2.0mm–2.5mm min. 5mm yes / no
Tungsten carbide Nickel HRC 56–60 1.0mm–2.0mm min. 6mm yes
Hard-facing Stellite 6 Stellite 12/1 Colmonoy 56 Tungsten carbide
Wear resistance •• ••• •••• •••••
Corrosion resistance ••• ••• •••• ••••
Attention: the chosen hard-facing has to be compatible with the barrel material!

To apply the hard-facings we use a state-of-the-art CNC operated PTA-welding machine. Our welding process ensures durable and robust hard-facings. Due to our CNC operated welding machine the quality is always at the same high level.

Detailed information on our hard-facings

Stellite 6

The structure of the Stellite 6 hard-facing consists on an austenitic matrix on cobalt basis with embeded Cr-W-carbides. Stellite 6 is a good compromise between tenacity and hardness. It is suitable for all applications, especially if a low number of cracks in the hard-facing is more important than wear protection.

Panzerung Stellit 6
Stellite 12 / Stellite 1

The structure of the Stellite 12 hard-facing is similar to Stellite 6 (austenitic matrix on cobalt basis with embeded Cr-W carbides). The amount of carbid builders (Cr/W) is higher than the one in Stellite 6, therefore Stellite 12 is harder and offers a better wear protection. Stellite 12 is the standard wear protection.

Panzerung Stellit 12
Colmonoy 56

The Colmonoy 56 hard-facing consists of an austenitic Matrix on nickel basis with embeded chromium borides, which are extremely hard. Colmonoy 56 does not only offer a better wear resistance than Stellite 6 and 12, but also a very good protection against corrosion, since it contains nickel instead of cobalt as basic material.

Panzerung Colmonoy 56
Tungsten carbide

The structure of our Tungsten Carbide hard-facing consists of an austenitic matrix on nickel basis, with up to 60% tungsten carbides embeded. This is the best available hard-facing. It has outstanding properties concerning wear protection as well as corrosion protection. Because of the very high hardness of this hard-facing, it is impossible to achieve a crack-free surface.

Panzerung Wolframkarbid

Important notice

For all kind of hard-facings it has to be taken into account, that tension cracks in the surface may occur. The harder the hard-facing, the higher is the number of cracks. But these cracks are a normal phenomenon which do not have any negative influence on the quality and lifetime of your screw.

Please do not hesitate to contact us in case of any questions concerning these cracks. We will be glad to support you in finding the optimum hard-facing for your specific application.