Bronze Mold Inserts, any alternative materials? 1

[henks580]

We currently use bronze inserts to hold our parts in place during injection. Vespel inserts were used in the past, but found to be brittle and damaged easily. Bronze has worked out well, but with increased production we need alternative material.

The most important characteristics, i think, are tensile strength and hardness. Basically, need material that will widthstand large forces without much deformation. Any other materials you may use in your own process are welcome suggestions.

(our process involves nylon 66-glass reinforced)

contact me for further information

 

[deper]

Are you speaking of inserts in a mold to hold something in place while you injection mold over it? Do the inserts stay in the mold or get ejected with the part? What is the problwm with bronze (cost, manufacture,....)?

 

[henks580]

Yes, the inserts hold the part in place while it molds. The inserts do not get ejected, they are fixed to the molds. The manufacturing and cost of bronze is a concern. Our automated robots damage the bronze inserts when the parts are inserted into mold. Curious to know if there are other materials available that would perhaps last longer (high thermal properties, as well as high tensile stress is desired).

 

[deper]

Have you considered aluminum?

 

[patprimmer]

Beryllium Copper is very effective, but also very costly.

Regards

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[engineer983]

Wouldn't it be cheaper to just fix the problem with the Robot? Maybe new end of arm tooling? We had used bronze inserts for years at my previous job. The only problem was when the robot wasn't set up properly, or press had incorrect setup.

 

[injectionmolder]

Engineer983 has a point by fixing the robot properly. Even if we find a stronger and inexpensive material that is hard to imagine, eventually the area of the robot that contacts the mold will get damaged. What I will do if the inserts currently need replacement, is going to aluminum as Patprimmer said and fix the set-up on the arms Robot.

Regards

 

[henks580]

Guys, thanks for all your input. I have been away and now I'm back. I am pleased to inform you that we have managed to come up with better ways to control our robot's position. In addition, we are also using a nickel/phosporous teflon coat on our inserts for strength and slick surface to reduce friction.

 

[Alexpsq]

if the insert was fixed in mold,i think maybe you need make a fixture for assembly!keep the fixture in the robot!
you shoud make a guide struction for the assembly!