Deep-hole bored conical barrel with honed finish. Machined in our own Henan workshop — to your drawing, or reverse-engineered from your worn parts.
A tapered bore has to be right along its whole length, not just at the ends. We deep-hole bore the taper, hone it, and check roundness and taper at several stations before it leaves the shop.
Ports and flanges machined to your layout; bimetallic lining available for filled or recycled PVC.
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.
| Bore | Tapered, conical twin geometry |
|---|---|
| Max diameter | Ø300 mm |
| Process | Deep-hole boring + honing |
| Ports | To your layout |
| Material | 38CrMoAlA / bimetallic |
| Inspection | Taper + roundness recorded |
| Lead time | 35–45 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 |
Yes if the body is sound — we line with alloy and re-bore the taper. We measure first and will tell you if it is not economical.
Ø300 mm in-house. Larger than that we decline rather than subcontract.
Yes, feed, vent and vacuum ports machined to your drawing.

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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.