Screws & parts
A feed screw only works properly when the tip, check ring, barrel and nozzle are right too. We look after the whole set.
The screw
We manufacture injection screws as a direct copy of the OEM part, working from your drawing or from the screw itself. Worn ones are rebuilt to their original tolerances. If a screw comes in without a drawing, we draw it and keep the drawing on file.
Tip and check ring
The tip assembly stops melt flowing back along the screw when it injects. It’s often called the non-return valve, and it consists of the tip, the check ring and the seat. When the ring or seat wears, the screw loses its seal, and shot size and cushion start to wander. We manufacture complete screw tip assemblies, or just the part you need: tips, check rings or seats. Ball-check types are covered too. Worn tip assemblies can also be refurbished.
Nozzles
We also manufacture nozzles and barrel end caps to fit your machine.
The barrel
On an injection barrel, the stroke wears the front end hardest. Rather than replace the whole barrel, we bore out the worn section and fit a short new sleeve, up to five times the bore diameter long. Sleeves come in nitrided EN41B, bimetallic or H13 through-hardened tool steel. If a new barrel is needed, we manufacture it nitrided or with a bimetallic bore.
Stuck?
If a screw has seized in its barrel, our 150 tonne press can push it out.
Get in touch
Mon–Thu 07:30–16:15 · Fri 07:30–15:00
Send us the machine make and the screw diameter. Call the workshop or send an enquiry through tws-ltd.com.
Call +44 (0) 1706 655402 Send an enquiry