Precision Brand PRE12930 O Rings Assortment 300 Piece

The Precision Brand PRE12930 is an O-ring assortment, 300 pieces.

An O-ring seals by being squeezed, and the number that governs it is not in this listing: the compound.

An O-ring's rubber determines what it can touch and what temperature it survives, and the wrong compound fails quickly and completely. Nitrile handles petroleum oils and fuels and is destroyed by brake fluid and ketones. Viton handles heat and aggressive chemistry and costs several times as much. EPDM handles brake fluid, steam, and water, and is destroyed by petroleum oil. Silicone handles extreme temperature and tears easily.

Those are not preferences. An EPDM O-ring in an oil system swells and disintegrates; a nitrile ring in brake fluid does the same. The failure is fast and it takes the system with it.

So verify the compound of this assortment before it goes to a customer — an assortment sold without one is a box of rings that might be right.

The other rule that belongs on any O-ring: the groove does the work. An O-ring must be squeezed by a defined amount, typically a fraction of its section. Too little and it leaks; too much and it extrudes and takes a permanent set.

Applications include hydraulics, pneumatics, and general sealing.

Brand

Precision Brand

SKU

PRE12930

Category

Fasteners

Weight

1.15 lbs

Dimensions

6.50 x 1.50 x 1.50

Price

$76.00

Availability

In stock

Rating

4.78 / 5.0