Classis car engine component repair
CIWS Gas Fusion welding process
Cast iron is a general description of an infinite number of material types that fall into the category. Even generic material designations like GGG50 or GGG60 does not describe the material at a molecular level.
The CIWS gas fusion process relies on the use of fusion rods (manufactured by CIWS) that match precisely the material of each specific component being recycled.
Thus, small samples of each component are taken, to allow selection of the correct fusion rod for the process to follow.
The rods are only available “in house” at CIWS. The constituent material comprises of the correct grade of cast iron, along with additives developed over decades of experience
Damaged areas are mechanically removed by mechanical means (grinding etc.). Sufficient material is removed to reveal sound parent metal.
The entire component is heated over a period of 12 to 18 hours to a temperature of between 500°C and 700°C, depending on the mass of the component and various other factors, not least the analysis of the material carried out earlier.
Gas fusion welding
Fusion of the new material takes place at a higher temperature, induced by gas torch, in the region of 1300°C. The parent metal becomes molten and the specially prepared fusion rod is induced.
CIWS developed flux is used to facilitate the successful fusion. The flux is applied to the fusion rods during the process.
The process is always carried out from above and, for this reason, the component is mounted on a gimble that allows rotation to any required angel to facilitate fusion to all required locations on the component.
The process is carried out by a skilled operator in 20-minute sessions (health and safety requirement). The process is completed in one operation, often taking 10 or 12 hours.
The operatives are qualified and are required to have their work tested on a regular basis.
The process is unique to CIWS and is only carried out in two location world-wide. (CIWS UK & CIWS Mexico).
It is vital that the component is fully stress relieved. Stress induced in normal operation (prior to the process) and further induced during the process, must be removed.
For this reason, the component is cooled in a controlled manor (up to 36hrs) determined by mass and material considerations.
At the end of the procedure, the component is fully stress relieved.