Hydraulic Piston rod

[demionkrishan]

Dear friends,
I have got a deep pitted and scoured ( about 4 mm in diameter) piston rod which is unable to salvage by HVOF coating. Customer need that desperately, can anyone suggest the best practice to rework on it?
will below mentioned practice will be fine? or need to change anything? could you guys please advise?

1. Pre machine and remove scoured mark
2. ARC Spray using 75B / 8400 -
3. Intermediate machining
4. grit blasting
5. Apply HVOF Chrome carbide 250-300 microns
6. Final grinding
7. Super polishing

Regards,
DK

[m_e_guerra]

Hi DK

I don't know the hvof technology (i just know something about the theory of the process) but i'm operator of an Arc Spray machine...

But, if the diameter it's appropriate, the steps are correct (I don't know about step number 5) Check the temperature when you rebuild whit arc spray, and the last layer of surface coating should start 0.7-1mm below of the nominal diameter (for possible off-centering of the piece, mainly if it's manually metallized)

I wish you a lot of success

[velocity]

I had same issue before please check my old threads. You van find good advices there. It works.