Z28-40 Thread Rolling Machine

The Z28-40 is an upgraded design built on decades of in-house thread rolling experience.

1. One-piece cast upper frame for greater rigidity.
2. Threaded bosses and wiring passages are cast into the frame, making automatic loading easier to fit.
3. A VFD motor and inverter can be added for stepless spindle speed.

The machine is rigid and well proportioned, with high driving power, low noise, a low failure rate and high thread accuracy. It rolls ordinary, trapezoidal and module threads, and can also form, burnish and knurl workpieces. Drive is through a universal shaft, lubrication is automatic, and control is manual, foot-pedal or fully automatic. Fitted with the right dies it produces a wide range of standard and special bolts.

Application. External threads including ordinary, trapezoidal and module threads, plus forming, burnishing and knurling. Suitable materials are carbon steels, alloy steels and non-ferrous metals with elongation above 10% and compressive strength below 100 kgf/mm².

Structure. Both spindles rotate synchronously in the same direction; the right spindle feeds horizontally under rolling force so the two dies form the thread. The machine consists of the bed, gearbox, fixed and moving spindle heads, hydraulic system and electrical controls. Spindle centre distance is set by adjusting each head to centre, which places the workpiece on the machine centreline and makes it easy to roll long parts through the machine. The spindle axis can be set within ±3° of the table, and axial feed per revolution is chosen from the workpiece data and material properties.