Industry New

Hydraulic two roller thread rolling machine for hollow fully threaded rod

Technical parameter:

Z28-200 including 1 set roller

Rolling thread range Diameter 64mm

Max thread pitch 6mm

Spindle angle ±10° Max rolling pressure 300kn

Spindle RPM 22/28/35/45/56/70rpm

Roller size range Outside diameter

210mm Hole 75mmMax width 150mm

Rolling time 0.1-99.9s

Rest time 0.1-99.9s

Spindle drive power 11kw

Hydraulic transmission power 5.5kw

Cooling pump power 90w

Dimension 1900*1700*1450mm

Weight 2500kg

Working Principle of Hollow Fully Threaded Rod Thread Rolling Machine

The hollow fully threaded rod thread rolling machine forms external threads on hollow pipes or tubes through cold extrusion plastic deformation, not cutting.

1. Feeding; Clamping

The hollow tube blank is automatically fed into the machine and firmly centered and clamped. Stable positioning prevents deformation or bending during rolling.

2. Two-Roll Synchronous Extrusion

Two high-hardness thread rolling dies are around the hollow tube.

• The dies rotate synchronously and apply uniform radial pressure from two directions.

• This balanced force avoids tube collapse, ovality, or deflection—critical for hollow workpieces.

3. Cold Rolling; Plastic Forming

Under controlled pressure, the surface metal of the hollow tube flows plastically into the die grooves.

• Threads are formed by extrusion, not removed by cutting.

• The metal fiber structure remains continuous, making threads stronger and more wear-resistant.

4. Full-length Thread Forming

The machine moves axially or feeds continuously to form full-length threads along the entire tube.

• It ensures consistent pitch, diameter, and thread profile.

5. Unloading; Finishing

After rolling, the formed hollow fully threaded rod is automatically discharged.

The thread surface is smooth and precise, requiring no secondary machining.

Core Advantage in One Sentence

This machine uses two-roll balanced cold extrusion to form high-strength, full-length threads on hollow rods without cutting, chips, or tube deformation.

two roll thread rolling machine, zhihaomachinery