ZLYJ Single Screw Extruder Gearbox

A technical product page that explains what makes the ZLYJ family suitable for single-screw extrusion and what must be checked before selection or replacement.

Suggested opening copy

The ZLYJ series is a dedicated two-stage gearbox family for single-screw extrusion service. Its selection is defined not only by power and reduction ratio, but also by the screw-side thrust system, output interface, mounting geometry and the operating duty of the extrusion line.

What the ZLYJ gearbox does

ZLYJ is a two-stage single-screw extruder gearbox family. Its job is to reduce motor speed to the screw operating speed, transmit the required torque and provide a dedicated output/thrust arrangement for the extrusion process. The output system is therefore part of the machine interface, not just a rotating shaft.

Why axial thrust belongs in the selection

Pressure in the extrusion process creates an axial reaction along the screw. That load is transmitted back toward the gearbox and must be carried by the thrust-bearing system. Motor power and ratio alone do not describe this load path, so axial-thrust capacity and the thrust-interface geometry must be checked independently.

Screw diameter is an interface clue, not a complete selector

Screw diameter helps identify the physical scale of the machine, but it cannot by itself determine the gearbox. Two machines with similar screw diameters can operate at different screw speeds, torque levels, pressure conditions and duty cycles. Use the screw diameter together with the required operating point and actual interface dimensions.

Ratio and speed should be checked as a system

The required screw speed normally establishes the reduction requirement when the motor speed is known. For replacement work, verify both the nominal ratio and the actual output-speed requirement. Do not assume that two catalog entries with the same nominal ratio have identical internal gearing or exact speed.

Mounting and output interface verification

Before replacing an existing ZLYJ gearbox, record the base dimensions, mounting holes, center height, input shaft, output spline or coupling geometry, thrust-interface diameters and bolt pattern, and the available axial installation space. Fits and tolerances are part of the interface and should not be omitted from the comparison.

Lubrication, cooling and service access

The lubrication arrangement must suit the speed, load and bearing layout. Where forced circulation or external cooling is used, pump flow, oil condition, filter condition and cooling performance become part of the operating system. Keep enough service access for oil level checks, draining, breather maintenance and coupling inspection.

Recommended technical figures

Use only the verified/sanitized engineering figures already cleared in the final technical-document system or new CHINFAR-owned visuals. Do not recreate unverified mechanical geometry.

• ZLYJ/ZSYJ exploded structure reference
• ZLYJ dimensional reference

FAQ