Does it really matter ?

[Qcprick63]

We're creating a chamfer by pressing a form pin up against a relatively sharp corner in a bore. The chamfer forms between a face and a thru bore. So we used an arbor press. I measured the force at about 750 lbs. So now we are buying a pneumatic press. It has adjustable speed and force. Does it make a difference if I use a much higher speed (like a hammer hit) and a lower force , or a slow speed with a higher force? Since we are displacing material, does the speed at which I displace the material matter?

 

[TugboatEng]

Galling can become more of an issue if you press it faster.

 

[Compositepro]

Strain rate is an important factor with work-hardening alloys such as some stainless steels.

 

[SnTMan]

As is so often the case, the answer is "It depends..."

Regards

Mike

The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[EdStainless]

What material are the two parts?
How deep is the interference part of the fit?
What is the size of this pin?

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed

 

[LittleInch]

The control of the actual force at higher velocities becomes much more difficult to maintain within a set band. you get more transient things happening at higher speed which are more difficult to control and replicate many times.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[Qcprick63]

The Material is incut 200. It has been carbonitrided to 55-60 HRC. Case depth is .008-.013. I am pressing a carbide form pin on to a corner.

 

[Dhurjati Sen]

Basically you want to play with the velocity and the height of the ram. But the total energy supplied to the blow remains the same.
Now, the pressure needs to be calculated for the plane on which the total load (from the energy supplied above) is applied.
Wherever the pressure is higher, more material is displaced.

DHURJATI SEN
Kolkata, India

 

[mfgenggear]

yes do not use high speed, it will damage components, slow, with pressure,
what is the actual interference fit, you may try shrink fit as well, however a small pin will not change much, is there a lead in on the pin and hole, are use oil to lube, heat the part and freeze the pin it may or may not help.
more visual is required for better answer
are there assembly tools involved

 

[Qcprick63]

This is a coining operation, not a press fit. The parts do not remain together. Essentially, we are making a dent.

 

[mfgenggear]

picture