Main Description
The mandrel works together with the roller and make the perforated tube blank into seamless steel tube with different size.To the rolling model, there are three kinds:floating mandrel, retained mandrel and semi~retained mandrel.We could offer different mandrels according to your different requirements.


The retained mandrels manufactured by our factory are sold to many domestic countries who needed to imported retained mandrelsbefore. We could design and manufacture mandrels used in rollers such as MPM, PQF, FQM, etc.

Diameter scope is Φ80~350mm; Length:2500~17500mm; Material: AISI H13 or 4Cr5MoSiV1

The retained mandrel for the production of large-sized seamless steel pipe is used in sectional structure. Its working section is exposed to complex and huge surface pressure as well as thermal cold-hot fatigue, whereas its connection part has to withstand mechanical forces during the pressing process.

The working part of the retained mandrel produced adopts H13 hot-work die steel or other alloy steel. The many production processes, that include smelting, forging, rough machining, heat treatment, semi-finished & finished machining, chrome plating and phosphate treatment, ensures the following characteristics: upgrading the mandrel material and its manufacturing technology in close collaboration.

Chemical Composition:

Element	C	Mn	Si	P	S	Cr	Mo	V
(%)	0.35-0.42	0.20-0.40	0.80-1.20	≤0.008	≤0.005	4.80-5.50	1.20-1.40	0.80-1.20

Mechanical Property

SIZE (Q+T)	Tensile Strength MPa	Yield Strength MPa	Elongation %	Reduction of area %	Average impact Akv J	Hardness HB
≤200mm	1127-1274	≥931	≥8	≥25	≥20	350-390
≥200mm	1078-1274	≥882	≥8	≥25	≥20	330-375