Polyurethane Timing belts

[marcotonin87]

Hi everyone

I am a materials engineer who works in the industry of polyurethane timing belts. Timing belt are extruded in rolls and contains steel wires as reinforcement which run in belt direction. We are facing a project in which a customer asked us to leave the two lateral wires with no polyurethane on them for the last 10 cm of the belt (the belt is not a closed ring, it is open end). It is quite complicated because the remaining wires have to be cut without damaging the lateral ones, which have to be very clen in order to allow their connection to an external electrical circuit which is used to check the conditions of the belt. I can do it for a single product by using a hot air flow, melting some polyurethane, but I can I implement this in a production line?
What about using an hollow punch on the finished product? Or is it possible to extrude the belt already with wires out?
Notice that the belt is produced in continuous: each end of a single piece corresponds to the beginning of the next one (each piece is cut using a particular saw - for ferrous materials cutting)
Below in grey the two lateral cords are reported, the black draw is represents the belt.

 

[MintJulep]

Does your process look like this?

https://www.youtube.com/watch?v=Njt5CCuAz4E

 

[marcotonin87]

Yes. it is very similar

 

[MintJulep]

Pull the two outside wires out of the extruder's width when you need them not coated.