Pneumatic and Hydraulic Cylinder Presses
Risk Assessment
Safety requirements, standards, and best practices should be used for designing and implementing safety systems in cylinder press applications. These presses, commonly used in manufacturing for tasks ranging from wiring harness assembly to metal forming, are simple yet powerful machines capable of exerting significant force. Due to their potential hazards—especially during motion at the point of operation—robust safety control systems are essential.
Applicable Safety Standards
Safety standards including ANSI B11.2:2013, CSA Z142:10, and ISO 16092-4:2017 emphasize the need for control reliability and performance levels (PL) in safety-related functions. These standards mandate that systems must prevent hazardous motion in the event of a single fault and maintain a safe state until the fault is resolved. Specific provisions are made for pneumatic presses and multi-cylinder systems, requiring monitored restraint devices to prevent unintended gravity-induced motion. ISO 16092-4 further details performance level requirements based on the type of input device and the nature of hazardous movement. For example, systems using light curtains or two-hand controls must meet PL d or e, depending on the application. Redundancy across inputs, logic, and outputs is important to achieve control reliability, warning against the use of single-channel valves that could fail and compromise safety.
Risk Assessment
Risk assessment is a critical and iterative process, involving calculations for stopping time, force, gravity effects, and failure modes. Various safety configurations are applicable, including Category 1 non-monitored systems, Category 3 monitored load holding, and Category 4 safe return and control systems. There are also limitations of mechanical devices not designed to stop moving cylinders and only certified safety-rated components for effective load holding and pressure relief should be used.
Final Thoughts
Selecting the right safety solution for pneumatic and hydraulic cylinder presses requires a thorough understanding of applicable standards, machine-specific risks, and operational requirements. ROSS Controls offers expertise and certified safety products to help manufacturers design systems that ensure both productivity and operator safety.