Bohler WEARstick Co 21 (Cobalt Alloys) Stick Electrodes

Bohler wearstick Co21 are specialised rutile coated stick electrodes with a cobalt base core wire, meticulously designed for high performance hardfacing and overlay applications. Formulated to handle extreme environments, it is equivalent to the UTP Celsit 721 designation.

This alloy is particularly well-known for its excellent structural integrity when exposed to harsh thermal cycles, aggressive chemicals, and heavy physical impacts. It offers a powerful shield against a combined assault of impact, pressure, abrasion, corrosion, and thermal shock, which is typically used in the following sectors, valves and fittings - Cladding running and sealing faces on gas, water, steam, and acid pumps/fittings. Combustion engines - Repairing and hardfacing valve seats and cones, hot-working tools -Overlaying extrusion dies, hot-working tools with fluctuating thermal loads, and machining tools, heavy industry - Critical components operating within gas plants, power plants, petrochemical units, and high-pressure steam environments.

• Operating temperatures up to 900°C.
• The pure weld metal yields a hardness of 31 – 37 HRC right after deposition
• work-hardening austenitic matrix, allowing it to toughen significantly under physical impact and pressure during operation
• Finely rippled weld bead
• Very easy slag removal

Technical Data

• AWS A5.13: ECoCr-E 
• EN ISO 14700: E Co1 
• DIN 8555 (Former): E 20-UM-300-CKTZ