Erosion due to drilling mud

[Dondomobilus]

Hi all, I'm designing a part for a downhole drilling tool which will see very high fluid speeds, mostly of very erosive drilling muds. The spec calls for 30 to 60 m/s fluid speeds, but I'm dubious I can get a material & surface coating combination which will not erode at that. It's a complex geometry so hard to make in solid tungsten carbide. Does anyone know whether HVOF carbide spray will withstand these fluid speeds and if not, what speeds should I restrict it to? Or any alternative approaches I should consider?

[djewell]

Any material is going to erode when it goes down hole. High density coatings (HVOF or preferably HVAF) are going to provide the best protection. I have seen erosion tests on HVAF done at the low end of the range of your fluid speed, and the coatings performed well. However, if there is any way you can slow down the speed, of course you will get longer life.