BÖHLER C 9 MV-IG is a TIG rod for welding creep-resistant CrMo steels. It is used on boilers, steam pipelines, refinery installations and parts working at elevated temperature.
The rod suits grades such as 1.4903 and ASTM A 335. It is used on boilers and pressure vessels under statutory inspection, and it covers root runs, thin walls and welds that need a smooth face.
- Classification EN ISO: W CrMo91
- AWS classification: ER90S-B9
- Diameters: 2.0 / 2.4 / 3.0 mm
Do not interrupt welding and do not let the joint drop below the interpass temperature before the fill is finished. Set the gas post-flow long enough for the pool and the electrode to cool under the shield. Grind the tungsten tip along its axis and hold a short arc, otherwise the pool spreads. Match the diameter to the material thickness and the welding position, thinner rods are easier to control out of position. Watch the hydrogen level, dry consumables and a preheated groove are your basic protection against cold cracking.
