Important technical terms

UHS steel
Abbreviation for ultra high strength steel.

ULC steel
(Abbrev. for ultra low carbon) Is a generic term for all austenitic Cr-Ni steels with a low carbon content, i.e. < 0.03 %. These classes are also suitable for difficult cold-deformations. Furthermore, the low C content results in a significantly better resistance against inter-crystalline corrosion, because the formation of the hazardous chromium-carbides is inhibited.

Ultrasonic test
With the ultrasonic test, a sound beam with up to 10 MHz is generated and mostly introduced into the specimen with water as coupling medium. In-homogeneities (defects) reflect a share of the sound energy when they are hit by the sound beam. These reflected sound waves can be received and displayed and/or detect the prospective size and location of the defect. The ultrasonic test is not bound to a special work-piece thickness, versatile applicable, un-hazardous and simple in its execution, but it requires much experience in the interpretation of the display.

Umbilicals
These are hydraulic control lines, which are used in the erection and maintenance of oil platforms for the control of tools and appliances under water (where divers can no longer work). Furthermore, it is possible by umbilicals to control the individual boreholes in the vicinity of several platforms by means of "remote control" from the shore with only one single control stand (e.g.: closing of the borehole in emergency) and thus to achieve substantial cost savings.

US-Wall thickness measurement
In a flawless component, the sound waves induced are reflected at the component back-wall; by means of the measurement of the time of flight (sound velocity known), the distance passed by the sound wave and thus the wall thickness can be determined.

U-tubes
Are manufactured from cold-produced seamless tubes on a tube bending machine and predominantly applied for the utilization in heat exchangers.