SK-25 as welding gas
SK-25 is designed for MAG welding of unalloyed and low alloy steels, especially where maximum penetration and efficient material transfer are required. The gas composition – 25% carbon dioxide in argon – provides a very stable arc, strong melt control and a fast welding process, while increasing the formation of spatter and surface oxides (slak). SK-25 is well suited for structures where mechanical strength and process efficiency of the weld are more important than visual finish.

Argon-carbon dioxide mixtures are the established choice for MAG welding, as pure argon alone is not sufficient to stabilise the arc in MIG welding of steels. An oxidising component – carbon dioxide – is essential to stabilise the arc and ensure uniform mass transfer. The high CO₂ content of SK-25 directly affects weld shape, penetration, welding speed and arc transition currents, making it an effective shielding gas for demanding production environments.

Rule of thumb:
– More argon → hotter and less risky welds
– More carbon dioxide → slightly colder sweat, more spatter, but better penetration.

Available grades:
Industrial SK-25

Packaging:
SK-25 gas is available in cylinders and cylinder packs.

Gases behave differently depending on their quality and state. Always consult the product’s safety data sheet before using the product. A safety data sheet is a document that conveys information about the properties, risks and safe use of a substance or mixture for industrial or professional use.

Risk of suffocation
An increase in the concentration of SK-25 gas in the breathing air poses a risk of asphyxiation. Low concentrations may cause increased respiratory rate and headache. Asphyxiation occurs unnoticed and can be fatal. As the air becomes heavier, it may accumulate in drains and basements and cause an increase in the concentration of SK-25 gas in the premises.

First aid
A person suffering from oxygen deficiency must be immediately evacuated to fresh air. If the victim is having difficulty breathing or is not breathing, administer artificial respiration as quickly as possible and call for help. When rescuing a victim, it is important to remember not to enter an oxygen-deprived area without breathing equipment.

Use
– When handling the substance, follow the instructions and safe working practices given
– The gas handler must be properly trained
– Use only carefully checked pressure regulators and other operating equipment suitable for this gas. If in doubt, contact Woikoske.
– Open the valve slowly to avoid pressure shock
– The valve is opened and closed by hand. The use of assistive devices is prohibited!
– It takes about one turn to open the bottle.
– The cylinder in use must be properly secured.
– Keep the valve outlets clean!
– Close the cylinder valve after each use and when the cylinder is empty.
– Always report damaged valves and cylinders to Woikoske.

Transport
– The driver must be aware of the potential dangers of the load and know his duties in the event of accidents and incidents.
– Cylinders shall be transported in an upright position
– The load must be secured
– Cylinders must not be knocked, thrown or dropped from the truck platform
– Attention to ADR regulations during transport

Storage
– Observe all legal and local requirements for the storage of cylinders.
– Store cylinders in a well ventilated area
– Cylinders should not be stored in conditions that promote corrosion
– Cylinders are stored upright and secured so that they cannot fall over
– Valve guards must be in place AT ALL TIMES
– Empty and full cylinders to be kept separate