Hardness/wear resistance of hardfacing rods

[Bill Edwards]

I've used hardfacing rods a few times over the years, but never really been able to look back at anything I've done with them and been able to compare their wear to ordinary rods.

Are there any figures that show just how much better they are compared with ordinary rods?
It's just that, when they're around £50 per tiny packet, I can't help but wonder if it isn't more economical to build a part up a little more with an ordinary rod instead, even if it has to be done a little more often?
If they're say 6x the price of ordinary rods, do they really last 6x longer?

Does anybody know just how much is actually gained?

 

[Hitch]

A lot of it for industry at least will be saving down time whist rewelding, let alone the labour cost involved.
We do a regualr job, nothing special, burn almost a whole 15kg (approx) of hardfacing wire in a day at about £250 or so a reel. (I think)
Time wise, the days labour will be more than the cost of the reel of wire. So effectively, if the hard facing lasts twice as long, the customer is in pocket.

There are different grades of it too, dependant on application.
Worth a look here...http://www.lincolnelectric.com/assets/US/EN/literature/C7710.pdf

 

[Bill Edwards]

Thanks, that's a very interesting read. I didn't realise there was such a choice depending on application. I can just imagine the blank faces I'd get though if I walked into some places and asked for some of those grades...

Sadly though they don't give any comparisons. I can understand that with the downtime and welders who are being paid a good amount hardfacing may be more cost effective, but I do suspect that it may not be the case for a farm job where the labor is relatively cheap and it wouldn't take long to run a few welds in every now and then as they wear.
It'd be good to work it out properly though!

 

[TechnicAl]

The life obviously depends on the application. Sometimes there is abrasion, erosion and corrosion, sometimes only one of those. The ultimate is the Chromium Carbide types, roughly 30%Cr 5% Carbon. Things like ploughshares last years longer if done with CrC.

 

[Jan]

When I was driving for a living I used to run in & out of various steel works in the Rotherham/Sheffield area. During 'Wakes Weeks' (shutdown fortnight) I was hauling (among other things) power picks back & forth for hard facing. They were being used for ripping the linings out of smelting furnaces where there had been a significant build up of hardened steel which had to be removed before the actual linings could be tackled. How long they lasted I couldn't say, but it's obvious that the firm I worked for found them to be financially advantageous compared to simply replacing the picks. My best guess is there is, or should be, a series of hard facing rods for different applications.

 

[wyn]

I used to do a fair bit of hard facing on quarrying static plant and it made stuff last a lot longer.
There was a difference in types of rod.....for a while we used Metrode "methard 650" which was ok but "methard 950" was the longest lasting.

A few bits also had chrome carbide plates.........a 5mm mild steel plate with chrome carbide weld over the top.
I put one of these plates on the end of a conveyor for the stone to land on....i think it lasted around 10 years with stone landing on it 8 hours a day.