An electric pipe expander and intelligent control circuit for the electric pipe expander are provided The electric pipe expander includes a pipe expander body and a mandrel sliding cavity disposed on the pipe expander body. A chuck body capable of clamping a pipe to be processed is disposed at an opening end of the mandrel sliding cavity. A mandrel is slidingly connected in the mandrel sliding cavity, an outer side end of the mandrel is provided with an obliquely disposed pipe expanding cone, an inner side end of the mandrel is provided with an elastic body accommodating cavity. Flat keys are disposed on the mandrel, and an elastic body is clamped and disposed between the flat keys and a bottom surface of the elastic body accommodating cavity.

A multi-size adjustable mouth, expanding device comprises a machine frame; a lower spindle module having s a lower spindle and a first gear, the periphery of the front end of the lower spindle is configured with a mouth expanding convex ring to enlarge the tube mouth; an upper spindle module, which includes an upper spindle, a second gear, and an expanding concave wheel, the upper spindle front end is mounted on the front end of the machine frame in a form that it can be displaced upward and downward, the periphery of the expanding concave wheel is configured with a mouth expanding groove, and the mouth expanding groove is placed on the upper side of the mouth expanding convex ring; a driving device, which is connected on the rear end of the lower spindle, and which is used to drive the lower spindle to rotate.

An electric pipe expander and intelligent control circuit for the electric pipe expander are provided. The electric pipe expander includes a pipe expander body and a mandrel sliding cavity disposed on the pipe expander body. A chuck body capable of clamping a pipe to be processed is disposed at an opening end of the mandrel sliding cavity. A mandrel is slidingly connected in the mandrel sliding cavity, an outer side end of the mandrel is provided with an obliquely disposed pipe expanding cone, an inner side end of the mandrel is provided with an elastic body accommodating cavity. Flat keys are disposed on the mandrel, and an elastic body is clamped and disposed between the flat keys and a bottom surface of the elastic body accommodating cavity.

An arrangement for working a tube end includes: an operating cylinder with a piston displaceable along an longitudinal axis; and a tube mounting, a tool holder being provided at an end of the piston facing the tube mounting. The operating cylinder is provided as a tandem cylinder. At least two cylinder stages are offset along the longitudinal axis. The piston includes connected piston segments, each piston segment being allocated to a cylinder stage.

A pipe flaring device is described. The device includes a main body extending along a mainly longitudinal direction. The main body also includes a flaring unit. The flaring unit interacts with an end of pipe to be flared. The main body also includes a die carrier arranged at the front of the flaring unit; and a flaring die. The flaring die includes a center channel which houses the pipe to be flared. The device includes a conical inner surface whose tapered end diverges towards the flaring unit and so that the inner surface matches a conical outer surface of the flaring die.

An electric pipe expander and intelligent control circuit for the electric pipe expander are provided The electric pipe expander includes a pipe expander body and a mandrel sliding cavity disposed on the pipe expander body. A chuck body capable of clamping a pipe to be processed is disposed at an opening end of the mandrel sliding cavity. A mandrel is slidingly connected in the mandrel sliding cavity, an outer side end of the mandrel is provided with an obliquely disposed pipe expanding cone, an inner side end of the mandrel is provided with an elastic body accommodating cavity. Flat keys are disposed on the mandrel, and an elastic body is clamped and disposed between the flat keys and a bottom surface of the elastic body accommodating cavity.

A tube diameter expanding method includes: rotating a tube having one end fixed to a turntable about a center axis of the tube; inserting a rod-like roller which extends in an axial direction of the tube into the tube from another end of the tube, and bringing the rod-like roller into contact with a forming region extending from the other end to a predetermined position of the tube; heating the forming region of the tube; cooling at least a section located near the forming region and within a non-forming region extending from the predetermined position to the one end of the tube; and moving the rod-like roller in a state of contacting the forming region of the tube, in a direction from the one end of the tube toward the other end of the tube and outward in a radial direction of the tube.

A combination of roller tools is used to cold work a pipe element and impart a desired shape to the sidewall. The roller tools are movably mounted on a frame. Segments of the roller tools align with one another during operation. The roller tools are used in a method of roll forming wherein the sidewall of the pipe element is compressed between the rollers.

An arrangement for working a tube end includes: an operating cylinder with a piston displaceable along an longitudinal axis; and a tube mounting, a tool holder being provided at an end of the piston facing the tube mounting. The operating cylinder is provided as a tandem cylinder. At least two cylinder stages are offset along the longitudinal axis. The piston includes connected piston segments, each piston segment being allocated to a cylinder stage.

A pipe flaring device is described. The device includes a main body extending along a mainly longitudinal direction. The main body also includes a flaring unit. The flaring unit interacts with an end of pipe to be flared. The main body also includes a die carrier arranged at the front of the flaring unit; and a flaring die. The flaring die includes a center channel which houses the pipe to be flared. The device includes a conical inner surface whose tapered end diverges towards the flaring unit and so that the inner surface matches a conical outer surface of the flaring die.