L20 UCM Valve

The L20 UCM valve is a solenoid-controlled valve, functioning as a crucial component in the safety architecture of hydraulic elevators. Its primary function is to allow unimpeded oil flow from the power unit to the cylinder during upward travel while preventing reverse flow until the solenoid valve is energized. This feature serves as a secondary safety measure, preventing unintended car lowering in case of uncontrolled car movement (UCM), thereby complementing the main control valve’s safety mechanisms.

The L20 is designed for direct installation on the cylinder port of a Blain EV ¾” valve, eliminating the need for adapters. It can function as a standalone safety valve when connected to an existing Blain EV valve with a separate tank line, making it suitable for modernizing older installations. Alternatively, the L20 UCM valve can be integrated with Blain’s EVL valve, removing the requirement for a separate tank connection.

For roped hydraulic elevator systems, an additional safety layer is provided by our optional LK piston safety system (or slack rope valve). This system is particularly useful for elevators with indirect transmission, such as 2:1 roped systems. The LK system prevents slack rope conditions by stopping the piston from lowering when the car is suspended in the safeties or resting on the buffers, further enhancing the overall safety of the elevator.