What is a more reasonable hardness level for the heat-treated stem of 17-4PH?
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What is a more reasonable hardness level for the heat-treated stem of 17-4PH? Just solution treatment + aging?
580 aging treatment, HRC 31~35 – this range provides good strength and toughness
We recently inspected Agus’ valve stems, and all of them were made with a hardness of HRC40. I feel that this hardness level is too high, which may lead to brittle fracture. If what you suggest is followed, I could make the stem body have a hardness of HRC31-35, and then harden the areas subject to wear to HRC40-45. Would it be possible to use cobalt-based welding rods for surfacing, followed by aging treatment or high-frequency quenching?
We recently inspected Agus’ valve stems, and all of them were made with a hardness of HRC40. I feel that this hardness level is too high, which may lead to brittle fracture. If what you suggest is followed, I could make the stem body have a hardness of HRC31-35, and then harden the areas subject to wear to HRC40-45. Would it be possible to use cobalt-based welding rods for surfacing, followed by aging treatment or high-frequency quenching?
This material is a martensitic type of pad-hardening stainless steel, and cracks tend to form easily during welding; if you want to improve its wear resistance, it is recommended to use WC for cold spraying
I have a wear-resistant sleeve that fits over the valve stem. The inner hole of this sleeve is spray-welded with a nickel-based material; the hardness resulting from this spray welding is around HRC42-45. I’m torn between options – I want to raise the hardness of the valve stem to HRC40 so that it can fit properly with the sleeve. But I’m worried that if the hardness of the valve stem is increased too much, it might break
The stem hardness of ARGUS ball valves doesn’t seem to be that high; if it’s 40, then it was probably manufactured from rod material in an annealed state.
That’s true. We currently have sizes of 4”, 8”, and 12”, all with an average hardness of HRC40. So, what is your routine method for improving the wear resistance of valve stems? Do you use WC spraying?
Hehe, in coal chemical industry, for valve stems and bushings, the hardened pairing used is WC/NI60
You can consider laser (local) quenching or laser cladding (powder spray welding), which offer unique advantages. We offer processing services. If you need more detailed information, feel free to ask. Mobile phone (WeChat): 135-1168-5308. Wu Jun
Laser quenching can be tried, with very little deformation. If methods such as surfacing are used, the process is relatively complex.