When installing add-on check valves and flashback arrestors, what must be ensured?

Ensuring that the arrow matches the desired gas flow direction is crucial when installing add-on check valves and flashback arrestors. This is because these devices are designed to control the flow of gases and prevent backflow, which could lead to dangerous situations such as flashbacks or explosions. If the arrow indicating gas flow is misaligned, it could allow gas to flow in the wrong direction, compromising safety and the functionality of the cutting equipment.

Understanding the specified direction helps maintain a safe and effective operation during oxyfuel cutting processes. The design of these components typically includes a clear indicator for the correct flow path, and adhering to this guideline ensures proper installation and operation.