A rotary crimping tool assembly includes a tool housing defining a crimping chamber, and one or more crimp wheels within the crimping chamber. The crimping chamber is configured to receive the portion of the structure in proximity to the crimp wheel(s). The crimp wheel(s) are configured to be pressed into and rotated relative to the portion of the structure to form one or more crimps in the portion of the structure.

A rotary crimping tool assembly includes a tool housing defining a crimping chamber, and one or more crimp wheels within the crimping chamber. The crimping chamber is configured to receive the portion of the structure in proximity to the crimp wheel(s). The crimp wheel(s) are configured to be pressed into and rotated relative to the portion of the structure to form one or more crimps in the portion of the structure.

A manufacturing method of a seamless metal pipe includes determining whether a preceding-stage stand group is used in outer diameter reduction or in thickness reduction of a hollow shell; and performing elongating on the hollow shell, into which a mandrel bar is inserted, based on the determination. In addition, in the elongating, when the preceding-stage stand group is used in the outer diameter reduction, the hollow shell is rolled in a state where an inner surface of the hollow shell does not come into contact with the mandrel bar in the preceding-stage stand group, and the hollow shell is rolled in a state where the inner surface of the hollow shell comes into contact with the mandrel bar in the succeeding-stage stand group.