Used Extruders

The screw design decides what an extruder can do. A single-screw machine has three zones along its length. The feed zone conveys solids, the transition zone compresses and melts them, and the metering zone pumps a steady melt to the die. Barrel length is stated as a ratio to screw diameter, the L/D. Most single-screw machines we handle run 24:1 or 30:1. Longer barrels with vent ports and vacuum pumps strip out moisture and volatiles. At the short end, 10:1 dump extruders with ram or stuffer feeds sit under an internal mixer and take each batch as it drops. Single-screw sizes here range from 0.25-inch lab Microtruders to a 12-inch dump extruder.

Twin-screw extruders come in two families. Co-rotating machines have intermeshing screws that turn the same way. Their screws and barrels are built from segments, so kneading blocks, side feeders, and vents can be placed where the formulation needs them. That flexibility is why co-rotating twins handle most compounding work. Counter-rotating machines turn their screws in opposite directions and build pressure with less shear. They come in conical and parallel designs and are widely used for rigid PVC. Twin-screw sizes in this category range from 3 mm to 133 mm, with L/D ratios from 20:1 to 56:1.

Model families recur, and buyers often search by them. We handle Werner & Pfleiderer and Coperion ZSK co-rotating twins, Leistritz ZSE and Micro 18 extruders, APV and Baker Perkins MP twin-screws, Davis-Standard Gemini conical and parallel twins, and PTI Trident single-screw extruders. At lab scale we see Thermo Fisher Scientific Pharmalab twin-screws, Xplore Technology micro compounders, Randcastle Microtruders, and Brabender Plasti-Corder torque rheometer extruders.

For a complete system with the die and downstream train already matched, see our used extrusion lines.

Applications & Industries

• Plastics compounding and processing: blending fillers, colorants, and additives into resin on co-rotating twins, and melting and pumping resin to film, sheet, pipe, and profile dies on single-screw machines.
• Pharmaceutical manufacturing: hot-melt extrusion of active ingredients into polymer carriers, and continuous twin-screw granulation. Leistritz ZSE pharma extruders and stainless steel Thermo Fisher Pharmalab machines come through this category.
• Rubber and elastomers: cold-feed rubber extruders and preformers, plus short dump extruders that discharge an internal mixer and feed a pelletizer.
• Chemical processing: high-pressure extruders that shape catalyst and other pastes, and vented extruders that remove solvents and volatiles from a melt.
• Food and beverage: cereals, snacks, and pet food run on the same co-rotating twin-screw principle. Food-grade machines are a smaller share of what we handle than plastics extruders, so a sourcing request is often the faster route to a sanitary build.
• Laboratory and R&D: torque rheometers, micro compounders, and small single- and twin-screw extruders for formulation work and short trial runs before a process moves to production.

Specifications & Configurations

Design variants. Single-screw extruders, co-rotating intermeshing twin-screws, counter-rotating conical and parallel twin-screws, vented and non-vented barrels, cold-feed rubber extruders, dump extruders, horizontal ram extruders, vertical micro compounders, and torque rheometer drive systems with interchangeable extruder heads.

Common options. Vacuum venting systems, gravimetric and volumetric feeders, twin-screw side feeders, liquid injection, hydraulic screen changers, melt pumps, underwater and strand pelletizing systems, water baths with air wipes, and DC drives with SCR control or AC drives with variable-frequency control.

Why Buy Used

A new extruder is a build-to-order item, with lead times measured in months once the screw design, barrel layout, and drive are specified. A used machine of the same size typically costs a fraction of the new price, and it can ship in weeks.

The screw and barrel are the wear parts on an extruder, and both can be rebuilt or replaced. The gearbox, frame, and drive see far less wear, which is why machines built decades ago still trade on the used market. A segmented twin-screw can be reconfigured with new screw elements for a different formulation, so a used machine is not locked into the job it ran before.

Every machine is inspected when it arrives at our Cleveland, OH facility, and it is available for customer inspection before purchase. Refurbishment and run testing can be arranged upon request. Process validation for your own material and facility remains with the buyer.

Related Equipment

• Used Extrusion Lines
• Used Extrusion Downstream Equipment
• Used Material Handling Feeders
• Used Screen Changers
• Used Pelletizing Lines