Product Description
Atlas AT Z-21 Valve Seat is a precision-machined hydraulic component engineered for Atlas manual pallet jack pump assemblies, designed to maintain high-pressure seal integrity in critical valve applications. Manufactured in hardened steel to industry standards, this seating component ensures reliable sealing and optimal hydraulic performance under rigorous manual pallet jack operating cycles.
Compatibility: Fits pallet jacks made by Atlas, model AT Z-21. Alternate model: ATZ21; AT Z 21. SKU: AT Z-21
Specifications
Hydraulic
| Pressure Rating | Rated for manual hydraulic jack operating pressures up to 5,000 PSI |
Material & Construction
| Hardness | Surface hardness minimum Rockwell C35 |
| Finish/Coating | Machined, uncoated steel surface for direct hydraulic contact |
Part Numbers
| OEM Part Number | AT Z-21 |
Frequently Asked Questions
Q: What does the AT Z-21 valve seat do?
A: The AT Z-21 is a precision-machined hydraulic component that maintains high-pressure seal integrity in Atlas manual pallet jack pump assemblies. It sits in the pump valve body and creates the sealing surface where the poppet or spool contacts to control fluid flow.
Q: What is the pressure rating for AT Z-21?
A: The AT Z-21 is rated for manual hydraulic jack operating pressures up to 5,000 PSI. This covers the full operating range of Atlas manual pallet jack pump systems.
Q: What material and hardness specifications does AT Z-21 have?
A: The AT Z-21 is manufactured from hardened steel with a surface hardness minimum of Rockwell C35. The finish is machined uncoated steel, which allows direct contact with hydraulic fluid for optimal sealing performance.
Q: Why is the AT Z-21 machined without coating?
A: Uncoated machined steel is required for valve seat applications because the sealing surface must maintain precise dimensions and surface finish. Coatings would interfere with fluid film formation and compromise the seal. The Rockwell C35 hardness resists the wear caused by repeated valve cycling.
Q: What happens if the AT Z-21 valve seat wears?
A: A worn AT Z-21 allows internal leakage past the poppet, resulting in pressure loss, slower lifting speed, and inability to hold load. The pump must run longer cycles to reach relief pressure, generating excess heat. Replace the valve seat if pump pressure cannot reach specified levels.
Q: Does AT Z-21 have alternate model numbers?
A: Yes. Alternate model designations include ATZ21 and AT Z 21. All three formats reference the same component. Verify compatibility with your specific Atlas pump assembly before ordering.