Safety in Web Handling: Part 1 - Standards

Presented by Clarence Klassen

Web handling lines have multiple sources of energy and power. These sources may include thermal, radiation, hydraulic and pneumatic pressure, springs, gravity and rotational energy. We will discuss the safety aspects of rotational energy associated with drives in web handling. We will discuss how “safety drives” can be used to ensure that the rotation required in web handling machinery meets applicable safety standards. We will review the meaning of safety and category of safety as applied to industrial equipment.

All drives can be commanded to stop. This results in a very low safety category. All drives can be Locked Out/Tagged Out (LOTO). When properly implemented, LOTO results in the highest safety category with zero energy present. Standard drives can have additional safety components such as safety contactors and safety relays to increase the safety category to the level required following a risk assessment. In practice, this can result in a “safe off” condition. “Safety drives” have incorporated a “safe off” function. Additionally these “safety drives” can provide a “safe torque”, “safe speed” and “safe network communications”. These safety functions provide options to greatly improve the safety of web handling equipment when operators must interface with machinery. This may include special considerations during threading and cleaning of the line.