Anyone work in injection molding?

[Chris1234]

I’m thinking of moving to injection molding as maintenance.

Obviously the machines have a lot of hydraulics, and temperature control.

What generally are the problems with them?
(except heater bands and SSR’s!)

 

[Cadgey123]

I work with plastic extrusion plants, injection moulding is complex but once the programs are set nothing much is suppose to go wrong. Fault thermocouples, heaters and sensors I would say. Be ready to learn quick

 

[Chris1234]

Thanks.
I’m currently plastic extrusion, we get thermocouples, SSR’s and barrel vacuums on twin screws causing the most problems.

Injection molding machines tend to use their own specific computer system rather than a PLC don’t they?

 

[Michael Gerrard]

Injection Moulding techniques hammer the power factor of an electricity supply due to the heavily inductive nature of the demand, our customers include Shoeller Allibert who use a lot of large injection moulding equipment. The PF was between 0.65 and 0.9 across the supplies of the site. We installed power factor correction equipment and the electrical values seen on the system and electricity costs were reduced significantly.

 

[Deleted member 105018]

Hi mate. I don’t work in injection moulding but my field is automation and control. CNC, PLC etc. I imagine a good foundation in PLC control is needed. Scada, industrial Ethernet, profibus etc. If your using analogue inputs like thermocouples then be ready for loop calibration. 4-20ma signals etc. And I guess analogue outputs to servo valves. I’ve worked in maintenance for 18 years. Things are moving on really rapidly. If you can tap up your employer for a basic plc course then you’d be laughing.

 

[gnuuser]

as with any machine such as molding equipment electrically you wont have many issues with them, the primary concern is precision alignment. given the speed they tend to run at a slight mis-alignment will cause premature wear and excessive current draw. eventually the damage will get bad enough to crash the machine and cause extensive mechanical and possibly some electrical damage.
plcs, slcs in some form or another run most everything and the programming training you will need should center around the brands you are using.

 

[Chris1234]

Thanks, I’m not going to that company now, they’ve changed their mind about taking on a maintenance engineer!