The HQ4257 is an AS568-257 black Buna-N (Nitrile) 70 Shore A Quad-Ring supplied with an inside diameter of 5.859 in (148.82 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 6.137 in (155.88 mm). This quad-ring seats in a standard o-ring gland while offering improved dynamic performance.
As a material, Buna-N (Nitrile) delivers the most widely specified general-purpose sealing elastomer, strong abrasion and tear resistance. This material stands up to greases and lubricants, petroleum-based oils, and water. Rated temperature range runs from -40°F (-40°C) to 250°F (121.1°C) in continuous service. Verify compatibility before use with polar solvents or ketones. The profile itself contributes a parting line located away from the sealing surface and lower compressive load required to achieve a seal.
It sees regular use in automotive, hydraulic and pneumatic systems, and agricultural equipment.
HQ4257 ships individually. Nominal inside diameter is listed as 5 7/8 inch. Check the compound against your process media, pressure and temperature before committing to a design. APG can cross-reference from an existing part number, a drawing or a physical sample if this size is not an exact match.
Description *4257-366Y MINNESOTA RUBBER QUAD RING
Actual Inside Diameter 5.859 inch (148.82 mm)
Actual Outside Diameter 6.137 inch (155.88 mm)
Actual Cross Section 0.139 inch (3.53 mm)
Measurement System Imperial
Product Category O-Rings - Square/Quad - Premium