Wire Rod and Bars


Profile measurement of bars behind a three-roll reducing/sizing block at Swiss Steel AG.

Swiss steel produces very small lot sizes and therefore has to change sizes frequently. During start-up this requires dense control of diameter and profile along the billet to roll within the given tolerances as quickly as possible after size or grade changes.

Three-roll blocks can produce pseudo-rounds. When measured with a vernier gauge, these profiles show identical or very similar diameters at different angles even if their roundness is far out of tolerance. The result: product may be shipped as "in specs" although it does not meet size and ovality tolerances.

LAP have developed a patented measurement and evaluation method (patents DE 100 23172 and US 6.549.293 B2) which precisely determines the sizes and roundness regardless of asymmetric or three-lobed shapes, thus allowing optimal control of rolling trains with 2- or 3-roll stands.


  • Measurement at three-roll block
  • Patented evaluation method for three-lobed shapes (pseudo-rounds)
  • Improved handling of small lot sizes


Profile measurement of wire rod with multiple data display at Mittal Steel Walzdraht Hochfeld (formerly ISPAT Walzdraht Hochfeld GmbH).

The system at Mittal Steel Hochfeld consists of three gauge heads working independently from each other. They are network-connected to six independent visualisation systems. Anytime each terminal can display data from any gauge head or archived data

The system is connected to the Mittal Steel Hochfeld product data base, receiving customer and product specific data according to the rolling schedule. The measurement is carried out fully automatic. After the rod has been rolled, summarized measurement data is archived in the product data base. Thus, complete documentation of all rods produced is achieved. Production data can be viewed even after the stock has been shipped and customer claims can be analysed in detail at any time.


  • Several gauges measuring simultaneously
  • Network connection and product database
  • Complete documentation