Brief Introduction:

Pipe end sizing mill, mainly used for casing, aims to reduce the ovality of pipe ensure pipe dimensional precision after being processed by the straightener.
After end sizing, casing will have less quantity of screw thread on omissive coupling surface, this raise product rate.

Main Parameters:

Fundamental:

Based on the incline principle, the expanding force is increased, and bigger expansionary force can be obtained by smaller pulling force, and then realize expanding and sizing on pipe end.

Primary Structure of JDJ-340 Sizing Mill

● This mill is consisted of expanding head, supporting pedestal, oil cylinder, transmission device and base.
● The expanding head is made up of wedged block, inclined block and sectorial block.
The hydraulic oil cylinder pull rod pulls a polyhedral cone, make the sectorial block move on radial direction, and then realize expanding.
The proportional valve controls the hydraulic flow then decides the oil cylinder speed.
The final expanding size is decided by telescopic length (implemented by PLC controlled oil cylinder piston position) of cone.
Usually the expanding amount will be 0.8~1.5% of pipe diameter.
The expanding head and oil cylinder are installed on the supporting pedestal, having axial movement along the rolling guide on the base which is driven by servo motor ball screw drive.
● In order to protect the guide rail and ball screw，there is stainless steel cover on the base.
● An oil-returning slot is equipped on the base to recycle the lubrication.

Primary Structure of JDJ-460 Sizing Mill

● This mill is consisted of machine base, driven back-up roll, clamping device, knee type stock stop, floating beam, main hydraulic cylinder, tension bar, internal expanding and external contracting tools;
● Driven back-up roll can be lifted by hydraulic cylinder and equipped with electric limit device;
● Driven by the cylinder, two sets of clamping device fix the pipe. The hydraulic system is equipped with pressure regulator and detector, and clamping strength can be adjustable according to pipe specification;
● Knee type stock stop is driven by hydraulic cylinder;
● Floating beam equipped with internal expanding & external contracting tools on one side and with hydraulic cylinder piston rod on the other side, two ends interlinked on tension bar. The beam is guided by the tension bar and moves with the main hydraulic cylinder.
The linear position sensor on the floating beam will directly show the main hydraulic cylinder working stroke.
● The maximum working pressure of main hydraulic cylinder is 500T; and there is digital display on the machine.
● The tension bar adopts hydraulic pretension mode, connecting clamping device and main hydraulic cylinder device.