Matched screw and barrel for SJSZ 51/105 conical twin extruders. Machined in our own Henan workshop — to your drawing, or reverse-engineered from your worn parts.
The 51/105 is the most common conical twin size in the field. We keep the geometry on file and build matched sets — screws and barrel together, nitrided, with the flanges machined to your machine.
Send us the machine model or the worn set and we confirm dimensions before machining.
Quote within one business day. We reply with a matching proposal, delivery date and price — no generic catalogue PDF.
Standard range shown. Every dimension below can be changed to your machine, resin and output — custom manufacturing is our daily business.
| Model | 51/105 conical twin |
|---|---|
| Supplied as | Matched screw pair + barrel |
| Material | 38CrMoAlA nitrided |
| Hardness | HV 900–1020 |
| Flange | Machined to your machine |
| Options | Bimetallic lining for filled PVC |
| Lead time | 30–40 days |
The honest answer depends on your resin, not on price. Here is how we advise customers.
| Gas Nitrided (38CrMoAlA) | Bimetallic Alloy Lining | |
|---|---|---|
| Best for | Unfilled PE, PP, PS, ABS, virgin PVC | Glass-filled, mineral-filled, recycled, corrosive |
| Surface hardness | HV 900–1020, depth 0.45–0.7 mm | Alloy layer 2–5 mm, metallurgically bonded |
| Typical service life | Baseline | 3–5× baseline on abrasive resin |
| Cost | Lower | Higher, recovered through fewer stoppages |
| Certification | MTC with heat number | MTC + hardness records, third-party on request |
Very likely. Send the machine model or a photo of the nameplate and we check before you commit.
Nitrided for virgin PVC. Move to bimetallic if you run filler or recycle.
Yes, if your barrel bore is still in tolerance — send bore measurements and we set clearance to them.

Large-format conical twin set for big-diameter PVC pipe lines.
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Send your machine model, drawing or worn sample — we reply with a matching proposal and quotation within one business day.