Company News · Equipment

China's Largest Pipe Fitting Injection Molding Machine Lands at Qingfa, Taking Large Diameter HDPE Fittings to dn1600

China's largest pipe fitting injection molding machine has been delivered to Zhejiang Qingfa Piping. The 9,000-ton unit molds PE100 gas and water fittings up to dn1600 in a single piece, replacing welded fabrications and imports at those sizes. Mold changeover drops from six to eight hours to under 90 minutes.

The machine is a DP9000-GJ2100 two-stage injection molding unit from Shenda Machinery, part of Zhejiang Second Light Industry Group. It was delivered to Qingfa's plant in May 2026.

Two figures make it a record holder. Shenda rates the machine at 90,000 kN of clamping force, the highest of any injection molding machine built in China, and a single shot size of 2.1 million grams, which the maker says is the largest in the world. Shenda developed the unit in-house and built it to Qingfa's specification.

Those are the two numbers that decide what a fitting plant can mold at all. Qingfa now molds PE pipe fittings up to 1,600 mm in diameter in a single shot - a size that used to leave the molding press entirely.

What the machine does

The unit weighs roughly 1,000 tonnes, and the molds it carries are heavy in their own right, up to 120 tonnes each. Handling that weight is the reason the machine runs 32 self-propelled hydraulic clamps rated at 35 tonnes apiece, backed by a synchronous locking unit. All 32 clamps reach their preset pressure in about two seconds, and the controller blocks an injection cycle if any single clamp falls below target. Load is spread across multiple points rather than a few, so an oversized mold stays put while the cavity fills.

A mold of the size this machine is built for, around 120 tonnes, in the press at Qingfa.

Changeover is where this shows up on the shop floor. Moving a mold of this size used to take six to eight hours of manual clamping; the hydraulic system brings it under 90 minutes. Typical production parts run about 1.55 tonnes in PE100.

Why a dn1600 fitting in one piece matters

Injection molding of PE fittings runs into a ceiling. Machine tonnage and mold size limit the part, so most plants top out around dn630 or dn800, and anything larger is cut and welded from pipe. Welded fabrications are flexible and can be built to almost any geometry, but they cost more, take longer, and leave fusion joints inside the fitting body.

Molding the same part in one piece removes those joints. Dimensions come from the mold instead of from fit-up on site, wall thickness and ovality stay consistent from part to part, and there is no weld seam in the body to inspect or re-test. On a specification that has to hold at dn1600, that is the whole argument.

A dn1600 HDPE tee at Qingfa's Yuyao plant, awaiting dispatch.

Qingfa's own large-bore work has been heading this way since early 2026, when a dn1600 butt fusion tee passed its trial run in one go and went into production. The new machine extends the same one-piece approach to fittings that previously could not be molded at all.

Where these sizes get specified

Demand for dn1000-and-above HDPE fittings comes from raw water and drainage mains, gas transmission lines, industrial fluid systems and nuclear plant piping, where long runs between branches are normal and fewer joints means fewer points to inspect later. Project teams specifying large bores generally weigh three options: welding fabrication on site, importing a molding, or buying a factory-molded fitting from a domestic plant. The third is what this machine is for.

Connection method is usually the next decision. Engineers can compare the two main systems in electrofusion versus butt fusion, or work through sizes, SDR and pressure classes with the PE pipe fittings buying guide. Sizing notes for bigger bores are collected in large diameter HDPE fittings, dn630 to dn1600, and illustrated in the note on customized solutions for large-diameter PE pipelines.

The fitting range behind it

Qingfa produces electrofusion fittings (couplings, equal and reducing tees, 45° and 90° elbows, end caps, tapping and branch saddles), butt fusion fittings (equal and reducing tees, elbows, end caps, flange adaptors), PE ball valves and steel-to-PE transition fittings, in more than 3,000 items from dn20 to dn1600. Recent large-bore additions include a dn1600 HDPE equal tee in SDR17 PN10 and a dn1400 PE100 electrofusion coupler.

Behind that range sit 42 injection molding machines, close to 50 CNC machining units and more than 10 automated welding machines, with annual capacity of 10,000 tonnes of polyethylene fittings. Gas fittings and water fittings are molded to the same tooling standards but tested against different pressure and hygiene requirements.

About Qingfa Piping

Zhejiang Qingfa Pipe Technology Co., Ltd. has manufactured PE pipe fittings for more than 25 years from its plant in Yuyao, Zhejiang. The company works to ISO 4427 and ISO 4437 for water and gas systems, holds ISO, CE and KS certification, and supplies gas utilities, water utilities and distributors in Russia, Australia, Korea, the Middle East and Southeast Asia. Production capability is set out on the workshop page, approvals on the certificate page, and reference installations in the project gallery.

Questions engineers ask

Is this the largest pipe fitting injection molding machine in China?

On clamping force, yes - 90,000 kN is the highest of any injection molding machine built in China, according to the machine's manufacturer. No other pipe fitting plant in the country runs a unit of this capacity.

What is the largest HDPE fitting Qingfa can mold in one piece?

Up to dn1600 (1,600 mm) as a single molding on the 9,000-ton machine. Heavier or larger assemblies are still supplied as butt fusion fabrications, made to drawing.

Can a large-diameter fitting be supplied molded rather than welded?

Yes, up to dn1600. Send the drawing with diameter, SDR, pressure class and connection type, and we will confirm whether the part can be molded or is better fabricated.

Which standards do the fittings meet?

Fittings are produced to ISO 4427 / ISO 4437, EN 12201 / EN 1555 and GB 15558 for PE100 water and gas systems. Material is virgin PE100 from BOROUGE, Sinopec and equivalent suppliers, with full traceability on incoming batches.

Are non-standard fittings available?

Yes. Non-standard angles, unequal reducers and special end configurations are made to drawing. Details are in the note on customized solutions for large-diameter PE pipelines.

Need large diameter HDPE fittings for a project? Send your size list and SDR to our sales team, or browse the full product range. For a plant walkthrough before you specify, the contact page lists our details.

Tags: China's largest injection molding machine · world's largest shot size · large diameter HDPE fittings · HDPE pipe fittings · PE pipe fittings manufacturer · electrofusion fittings · butt fusion fittings · dn1600 HDPE fittings · PE100 fittings

Sources: Zhejiang Second Light Industry Group; Shenda Machinery; China Plastics Processing Industry Association; company production data.