Mandrel bars

Mandrel bars are used as piercing tools in the production of seamless hot-rolled tubes and pipes. Pre-pierced steel billets are rolled to hollows by means of mandrel bars. From these hollows, tubes and pipes are produced using a range of forming and finish-rolling processes. During the piercing process, the mandrel bars are subjected to extreme stresses, and the material properties and dimensions of our mandrel bars are therefore precisely adjusted to their specific conditions of use.

A carefully selected scrap charge to produce the liquid steel that is cast to ingots in moulds or blooms and billets on our highly productive continuous casting machines forms the basis for our tailor-made mandrel bars. The mandrel bars themselves are produced by rolling or forging, then quenched and tempered and, finally, surface-finished by peeling. They are finish-machined on CNC lathes. Then mandrel bars are given a scaled surface or chromium-plated.

We produce mandrel and shaft bars to ultra-tight diameter tolerances. Up to a length of 25 meters, for example, we peel the bar to a dimensional tolerance of not more than 0.05 millimeters. We supply mandrel bars in a large range of sizes and finishes. We assist our customers in the planning of new and upgrading of existing facilities, as well as the planning of full-line solutions that may even include the production of the feed material.