Making
of Welded Steel Pipes & Tubes:
These high performance pipes and tubes are alloyed with higher contents of
molybdenum and nitrogen to improve the corrosion resistance and the
strength, and are welded with over alloyed filler metals with nitrogen added
to the shielding gas, to become as high pitting corrosion resistance as
possible in the weld. Pipes made of nitrogen alloyed chloride resistant
grades in the presented applications are welded with the addition of
nitrogen in the shielding gas. Most of the pipes are also welded with filler
metal and heat treated when specified.
Types & Usages:
Depending on how and where the pipes will be used it is up to the end user
to decide which type of heat treatment is necessary. Chloride environments
give however a risk for pitting, crevice and stress corrosion for standard
steels. The pipes are used in all types of corrosive environments in
industries such as, chemical, metallurgical, energy, oil & gas, pulp &
paper, ships, desalination, and food. Welded steel pipes and tubing come in
improved design properties and are much higher corrosion resistance than
other conventional steel pipes. These pipes are also used in a number of
applications where high demands are set on reliability, strength and
corrosion resistance.