Hydraulic Packings
A complete line of hydraulic packing in varied styles, shapes, and sizes for any cylinder application: Vee-Packing, U-Cups, piston cups, flange packings, rod wipers, backup rings, and O-Rings.
Anchor molded packing sets are fabricated of special fabric impregnated with synthetic or rubber compounds that will resist the action of oils and hydraulic fluids. Pressure developed in the equipment, introduced against the packing, governs the outward expansion of the lips, and greater pressures serve only to increase the sealing action by increasing the tension of the lips against the rod and stuffing box bore.
When this pressure is relieved, the lips resume their normal position, allowing movement of the rod through the packing with minimum frictional drag. Anchor Seals Inc. stocks these packings in Buna-N, Viton, EPDM, polyurethane, Teflon, and leather constructions, in standard, AN, MIL, and AS568A sizes, and can cross-reference any existing style number to a current product.
Vee-Packing
Multi-lip chevron sets for rods and pistons. Pressure spreads the lips against the rod and bore, so sealing force rises with system pressure and relaxes when pressure drops.
| Style # | Description | Application |
|---|---|---|
| 915-DN | Cotton Fabric & Buna-N Rubber. Available with rockhard top & bottom adaptors. | For low temperature oil and solvents. Meets specification MIL-P-2911. |
| 915-DV | Cotton Fabric & Viton Rubber. Available with rockhard top & bottom adaptors. | For high temperature pneumatic and hydraulic applications. |
| 915-DF-9 | Cotton fabric & EPDM rubber. Available with rockhard top & bottom adaptors. | For non-inflammable hydraulic fluids. |
| 915-MAT | Polyurethane. | Hydraulic fluids, most petroleum based fuels and oils, acidic or alkaline solutions under 10% concentration, edible fats and oils, salts. |
| 915-L | Leather. | For pneumatic and hydraulic applications. |
| 1135-T | Teflon. | Conforms to AN-6225 sizes and dimensions. For all fluids and gases, temperatures to 450°F. |
| 1136-T | Teflon. | For all fluids and gases with temperatures up to 450°F. |
| 920-H | Ankorite homogeneous V-seals (snap on type). Conforming to AN-6225 sizes. | Outstanding for low friction load and long life as piston and rod seals in reciprocating service. |
| 900-DN AMFLEX | Heavy duty Cotton Fabric & Buna-N for deep stuffing boxes. | For high and low pressures, oils, solvents, water, steam, low temperature oils and solvents. |
U-Cups
Interchangeable with many Vee-Packings, Rubber U-Cups, and most O-Rings.
| Style # | Description | Application |
|---|---|---|
| 919-MS | POLYFLEX lip type seal. Polyurethane automatic lip type seal with squeeze type O-ring. | Useful for low to extremely high pressures through a temperature range of 200°F. |
| 919-MD | POLYFLEX lip type seal. Polyurethane automatic lip type seal with squeeze type O-ring. Deep height double bevel lips. | Useful for low to extremely high pressures through a temperature range of 200°F. |
| 919-MME | Polyurethane Modular Bushing. | For shock absorption. Safeguard against metal-to-metal contact. Effective as anti-extrusion backup for Polyflex seals in high pressure applications. |
| 923-U | Leather. Available in either straight or flared lips. | For pneumatic and hydraulic applications. |
| 923-H | Homogeneous U-shaped seal without fabric insert, produced in a variety of synthetic rubber compounds to suit a wide range of service requirements. | For pneumatic and hydraulic applications. |
| 924-F | Cotton fabric insert & Buna-N rubber with flared lips. | For low pressure applications, reduced friction, slightly over-sized bores, and in certain instances where equipment misalignment creates an over-sized clearance. |
| Spectraseal | Teflon spring energized U-shaped seal. Available with glass, carbon, graphite, bronze, and molybdenum disulfide fillers. Temperature range from -300°F to +500°F. | For static and dynamic, low and high speed applications. |
Washers & Backup Rings
Contoured support rings that back up lip seals and prevent extrusion under pressure.
| Style # | Description | Application |
|---|---|---|
| 5056-B | Buna-N contour, 90A durometer. | For pneumatic and hydraulic applications. |
| 5056-T | Teflon. | For pneumatic and hydraulic applications. |
| 5056-L | Leather. | For pneumatic and hydraulic applications. |
Flange Packings
Fabric inserted and leather flange style packings for hydraulic and pneumatic cylinders.
| Style # | Description | Application |
|---|---|---|
| 925-B | Cotton fabric inserted Buna-N hydraulic and pneumatic packing. Check for size availability. | For pneumatic and hydraulic applications. |
| 925-L | Leather. | For pneumatic and hydraulic applications. |
Piston Cups
Cup-shaped packings that seal the piston against the cylinder bore.
| Style # | Description | Application |
|---|---|---|
| 922-B | Ankorite molded fabric inserted cup-shaped hydraulic and pneumatic packing. | For oil, air, water, gasoline, solvents. |
| 922-H | Homogeneous rubber available in various rubber elastomers. Check for availability. | For low pressure pneumatic and hydraulic applications. |
| 922-L | Leather. | For pneumatic and hydraulic applications. |
| 922-MAT | Polyurethane. | Resists dimensional distortion during installation and service. Appropriate for higher pressures. |
Rod Wipers & Scrapers
Keep dirt and abrasives off the rod on the in-stroke and wipe residual fluid on the out-stroke.
| Style # | Description | Application |
|---|---|---|
| 921-H | Homogeneous Double Lip. Double lip configuration allows two jobs: on the in-stroke it wipes the rod clean of all foreign matter. On the out-stroke it functions as a closely conforming secondary rod seal, wiping the rod perfectly dry, free of hydraulic fluid. | For pneumatic and hydraulic applications. |
| 959 | Standard wiper rings, one-piece, snap-in type rod wiper-scrapers. Can be ordered in Ankofluor or Viton material. Conform in sizes and dimensions to MA-28776. | For pneumatic and hydraulic applications. |
| 959-D | One-piece snap-in wiper. Same construction and function as standard 959 wipers, but in larger cross-sections. | Heavy duty applications where extra bulk is needed, in addition to toughness and abrasion resistance, such as in the handling of abrasive materials. Also available in Ankofluor or Viton. |
O-Rings
Standard AS568A sizes in Teflon and a full range of rubber elastomers.
| Style # | Description | Application |
|---|---|---|
| 50 (AS568A dash numbers) | Standard molded AS568A sizes. Available in Teflon & various rubber elastomers. | For static and dynamic applications. Meets AN-6227B, AN-623B, military & aircraft specifications. Check for availability. |
Frequently Asked Questions
What is hydraulic packing?
Hydraulic packing is the family of lip seals, cups, wipers, and backup rings that seal the rod and piston of a hydraulic or pneumatic cylinder. Anchor molded sets are built from fabric impregnated with synthetic or rubber compounds that resist oils and hydraulic fluids, and the lips are shaped so that system pressure itself pushes them against the rod and bore.
How do I choose between Vee-Packing and a U-Cup?
Vee-Packing sets stack several chevron rings between adaptors and are the traditional choice for deep stuffing boxes, high pressures, and older equipment designed around them. A U-Cup is a single-ring seal that installs in a shallower groove and is interchangeable with many Vee-Packing sets, rubber U-Cups, and most O-Rings. If the groove is shallow or the cylinder is modern, a U-Cup is usually the simpler choice.
Which material should I specify?
Buna-N is the general purpose choice for petroleum oils. Viton handles higher temperatures and more aggressive fluids. EPDM is used for fire resistant, phosphate ester type fluids. Polyurethane offers the best wear and extrusion resistance for high pressure. Teflon covers nearly all fluids and gases to 450°F and beyond with spring energized designs. Leather remains a proven low cost option for general pneumatic and hydraulic service.
Do I need a backup ring?
Backup rings are recommended whenever pressure, clearance, or temperature could push a lip seal or O-Ring into the extrusion gap. The 5056 series contour washers and the 919-MME modular bushing are designed to sit behind the primary seal and take that load.
What information do you need to quote a packing set?
The rod or piston diameter, the bore diameter, the groove or stuffing box depth, the fluid, the operating pressure and temperature, and the cylinder manufacturer and model if known. A sample of the old packing or the style number stamped on it lets us cross-reference directly.
Are these packings available in military and aircraft sizes?
Yes. The 1135-T and 920-H Vee-Packings conform to AN-6225 sizes, the 959 wipers conform to MA-28776, the 915-DN meets MIL-P-2911, and our O-Rings are molded to standard AS568A dash numbers meeting AN-6227B and AN-623B specifications. Check with us for availability on a specific size.
