Durachrome VS ceramic material for rotating face of mechanical seals

[Mech5656]

Hello Engineers,

We need to repair some mechanical seals urgently and vendor is saying they can provide durachrome rotating face instead of ceramic rotating face, which original was per OEM. Can you provide your recommendation on this change? Will this change of material be fine? Will it work fine? Here is the pump process condition:

Service: auto clave quench water
Product: water
Temp: 90 F
Suction pressure: 8.7 PSIG and discharge pressure is 823 PSIG
SG: 1.0
Pump RPM: 3600
Viscosity: 1.0 CP

 

[JJPellin]

I have never heard of durachrome and could not find any information about it on line. I assume that this is some sort of sprayed on coating on a softer base material. In general, I would not consider this to be acceptable. A solid material would be much better. In order from best to worse, I would prefer Silicon Carbide, Tungsten Carbide, Ni-Resist, Ceramic, 17-4 PH stainless steel, Cast Iron. Yours is not a particularly difficult service. If this coated face is all you can get in a timely manner, it will probably run fine for a while.

Johnny Pellin

 

[TugboatEng]

Ni-resist is used on applications that see high thermal shock but otherwise ceramic will always perform better. Durachrome seems like an attempt to provide ceramic like wear and a better tolerance of thermal stress. In other words, if your application tolerates ceramic then ceramic will likely perform best.

 

[TenPenny]

If I recall correctly, Durachrome (or Durchrome) is an old Durametallic (now Flowserve) material, but all my old stuff is in the office and I'm working from home to avoid the Covid-19, so I can't confirm any more specifics. I think typically it is 316ss with a hard chrome plating on the face, but don't take that as gospel.