Sterling Hydraulics A04J2HZ4-90N Relief Valve

Sterling Hydraulics A04J2HZ4-90N Relief Valve is a direct-acting, screw‑in cartridge relief valve in Sterling’s A04J2 family, engineered to cap hydraulic system pressure by venting excess flow back to the reservoir when the set point is reached. It embodies Sterling’s cross‑over relief design, providing overpressure protection across connected circuit paths in compact cartridge form.

Construction and materials feature a screw‑in cartridge (C11 style) with an aluminum body and rubber packing, aligning with Sterling’s cartridge valve architecture that supports reliable, field‑installable protection within manifold blocks. The A04J2 series is built for rugged industrial and mobile hydraulic applications, where space and cost efficiency are key benefits of single‑cavity relief solutions.

Porting and connections for this family typically use threaded 1/4" NPTF interfaces, suitable for common cartridge valve installations, with configurations available to suit multi‑port relief needs in standardized Sterling manifolds. The model code A04J2HZ4-90N identifies a specific configuration within the cross‑over relief line, reflecting a defined set of operating characteristics and installation parameters.

Common applications include protecting hydraulic pumps, motors, and actuators in integrated valve blocks and compact power units, where precise, reliable relief behavior is required to maintain circuit stability and component longevity. This Sterling valve is part of a broader ecosystem of Sterling hydraulic cartridges designed for high performance and interchangeability within Parker Hannifin’s portfolio of gasketed, cartridge, and manifold solutions.