TG-FourShaft 400 Four-Shaft Metal Shredder

Four-Shaft Shredding for Controlled Particle Size

The TG-FourShaft 400 is a four-shaft metal shredder engineered for scrap processors who need tighter control over output particle size than a twin-shaft configuration can deliver. Two pairs of counter-rotating shafts work in sequence: the upper pair grabs and pre-cuts incoming feedstock, while the lower pair performs the final shearing pass through a screen basket that sets the discharge fragment size. This two-stage cutting action produces a more uniform particle distribution, which matters when downstream separation equipment-magnetic drums, eddy current separators, or briquetting presses-requires consistent feed geometry to operate efficiently.

Key Specifications

Drive power is split across two independent gearboxes, one for each shaft pair. This allows the upper feed shafts to run at a different speed than the lower cutting shafts, improving material pull-through when feedstock varies in shape and density. The screen basket beneath the lower shafts controls final particle size-swapping baskets changes the output fraction without replacing cutting tools.

How Four Shafts Differ from Twin-Shaft Designs

A twin-shaft shredder shears material between two counter-rotating shafts and discharges whatever passes through the gap between the shafts. Output size is governed by the cutting disc spacing and shaft gap, which means fragment size varies with feedstock geometry. A four-shaft design adds a second cutting pair below the first, paired with a perforated screen basket. Material remains in the cutting chamber until it has been reduced enough to pass through the screen openings. This produces a narrower particle size distribution.

The practical implication for buyers: if your downstream process requires a consistent fragment size-for example, feeding a briquetting press that jams on oversized pieces, or an eddy current separator whose recovery rate drops with irregular particles-the four-shaft configuration reduces the need for secondary screening and re-shredding.

Cutting Tools and Wear Parts

All four shafts carry bolt-on cutting discs manufactured from hardened alloy tool steel. The discs are individually replaceable without pulling the shaft assemblies, which keeps maintenance downtime to a single-disc swap rather than a full shaft extraction. Hard-facing is applied to leading cutting edges. The screen basket plates are wear-resistant AR400-grade steel and are bolted in for tool-free replacement.

• Cutting discs: hardened alloy tool steel, bolt-on, individually replaceable
• Screen baskets: AR400 steel, available in 20 mm, 30 mm, 40 mm, and 60 mm perforation
• Side liners: bolted wear plates, no welding required for replacement
• Shaft seals: labyrinth seals with grease purge, inspected during scheduled lubrication

Feedstock and Application Boundaries

The TG-FourShaft 400 is suited for medium-density scrap streams: aluminum profiles and castings, copper wire and cable bundles, light sheet steel offcuts, electronic scrap (WEEE) after battery removal, and mixed non-ferrous turnings. The upper feed shafts grip irregularly shaped items and draw them into the lower cutting pair without the bridging that single-shaft rotors experience with tangled wire or nested sheet.

Items that should not be fed without pre-processing include solid steel shafts or billets exceeding the shaft torque rating, sealed pressurized vessels, and any material containing free mercury switches or undrained batteries. For WEEE processing lines, confirm that batteries and capacitors have been removed upstream-the shredder reduces mechanical size but does not neutralize chemical or fire hazards.

Drive Configuration and Electrical Standards

The two 75 kW motors can be configured for 50 Hz or 60 Hz supply to match European or North American plant standards. Each motor has its own gearbox and coupling, so a mechanical issue on one shaft pair does not halt the entire machine-the other pair can be run in reverse to clear a jam. Soft-start and VFD options are available for plants with limited inrush current capacity.

Compliance and Certification

The machine frame and guarding carry CE marking per the Machinery Directive for European facility installation. For North American buyers, UL-listed control panel configuration and ANSI/OSHA guarding compliance are available on request. The manufacturing facility operates under ISO 9001 quality management. Confirm specific national-language documentation requirements and local electrical code compliance at inquiry.

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