The shape of internal burr appears when the used roll forming machines. There is a certain logical relationship between the shape of the burr in the welded pipe and the welding temperature, extrusion force and welding speed.

The operator can see the essence of the used roll forming machines through the phenomenon of the shape of the internal and external burrs.

The matching of welding process parameters is related to the shape of the transverse internal burr.

Transverse internal burr shape: Isosceles

Raw material of welded pipe: trimmed pipe blank

Weld butt joint: "I" parallel

Welding temperature: solid phase ~ solid solution

Squeeze force: too large

Welding speed: suitable

Horizontal internal burr shape: Double peak

Welded pipe raw material: round side tube billet

Weld butt joint: "X" butt joint

Welding temperature: solid phase ~ solid solution

Squeeze force: greater

Welding speed: suitable

Horizontal internal burr shape: Wedge

Raw material of welded pipe: cut edge/round edge

Weld butt joint: "N" misalignment

Welding temperature: solid melting ~ melting

Squeeze force: moderate

Welding speed: slow

Horizontal internal burr shape: Mushroom

Raw material of welded pipe: cut edge/round edge

Weld butt joint: "I"/ "X"

Welding temperature: melting

Squeeze force: greater

Welding speed: slow

Horizontal internal burr shape: Centipede

Raw material of welded pipe: cut edge/round edge

Weld butt joint: "I"/ "X"

Welding temperature: melting

Squeeze force: small

Welding speed: slow

The above are the types of internal burrs that appear when the used steel pipe is rolled by a machine-made pipe. The essence of the operating state of the used roll forming machines can be analyzed through the shape of the internal burr.