Disc Springs in Subsea Valve actuators

Disc springs are widely used in subsea valve actuators as high-force preloading and energy storage systems. In these large-thrust valve actuators for offshore and oil & gas applications, disc spring stack is typically installed behind the piston and around the central push rod, continuously applying axial force to the rod assembly.

In subsea actuators, disc springs act as compact high-force systems that store energy, maintain a constant preload, compensate for wear and thermal changes, and provide fail-safe functionality. Disc springs enable a nearly constant force throughout a short stroke, which is critical for dependable valve operation in high-thrust, space-limited applications.

In subsea and oil & gas environments, valve systems are frequently exposed to temperature fluctuations, pressure variations, and sealing wear. Disc spring stack helps compensate for thermal expansion and wear-related displacement, while maintaining a nearly constant preload force over a defined stroke range. This stable loading is critical for reliable valve sealing performance.

Another key function of disc spring system is fail-safe protection. In many hydraulic actuator systems, loss of hydraulic pressure or power failure requires the valve to automatically close or remain safely closed. The energy stored in disc spring stack can drive the valve stem during emergency conditions, making disc springs a critical safety component in subsea actuator design.

Compared with coil springs, disc springs provide clear advantages in subsea actuator systems:

• High force in compact space

     Very high load capacity with minimal installation space.

• Short stroke, high output

     Large force generated with small deflection.

• Flexible stacking design

     Series/parallel stacking allows easy load and stroke adjustment.

The image on the left highlights a subsea actuator project by OPTIMUM Disc Spring. For this application, OPTIMUM supplied a set of high-temperature INCONEL X718 disc springs. The spring stack consisted of 32 pcs disc springs and achieved a fatigue life of over 500,000 cycles under demanding subsea operating conditions.

Need expert advice? Contact our engineer today for customize solutions at jc@optimum-spring.com !