PMK PSKA Series locknuts are precision clamping nuts engineered to provide accurate axial positioning and secure preload for small‑ to medium‑sized spindle, shaft and bearing assemblies.

The PSKA family is optimized for applications that require repeatable torque‑controlled locking, compact form factor, and simple installation using a grub (set) screw for secondary locking.

Manufactured to close tolerances, PSKA locknuts feature machined seating faces and controlled thread geometry to minimise runout and preserve bearing life. The series covers common metric threads from M15 to M60 with clearly specified grub‑screw sizes, recommended grub‑screw torque, and final locknut tightening torque for safe, repeatable assembly.

Key benefits

• Reliable clamping: size‑specific tightening torque (20 → 365 Nm) ensures predictable preload and secure axial retention.
• Compact design: low axial height and optimized OD for limited‑space installations.
• Serviceable: grub‑screw secondary locking simplifies re‑use and on‑machine adjustments.
• Precision: ground bearing face and controlled threads for low runout and repeatable location.
• Clear assembly data: specified grub‑screw size and torque for correct installation.

Typical applications

• Bearing and spindle locking in CNC machine tools.
• Ball‑screw end clamping and rotary table locking.
• Toolholders, fixtures and precision indexing drives.
• Retrofit and OEM assemblies needing controlled preload and compact locknuts.