Field Notes on the 28-40-5.5 Tcv Oil Seal High Pressure Oil Seal

If you’re sourcing seals for tough hydraulic duty—travel motors, rotary pumps, vertical shafts—this size keeps popping up. To be honest, I’ve seen it in more excavators and road rollers than I can count. Made in the Development Zone, Julu County, Xingtai (which, by the way, has become a mini cluster for sealing tech), this part targets high-pressure, gritty, real-world jobs.

What it is (and why TCV matters)

The TCV structure is a metal-cased, double-lip rotary shaft seal with a garter spring and a dust exclusion lip. In practice, that means stable OD retention, good shaft follow, and better dirt rejection—handy when your “worksite” is a quarry slope in light rain. Many customers say this 28-40-5.5 Tcv Oil Seal High Pressure Oil Seal holds pressure without the drama, provided the shaft finish and runout aren’t neglected (more on that below).

Quick specs (real-world values)

Where it’s used

• Hydraulic pump/motor sealing (travel pumps, rotary pumps, vertical shafts)
• Earthmoving: excavators, road rollers, scrapers, loaders, dumpers, mixer trucks
• Gearboxes, power packs, marine auxiliaries (with FKM at higher temps)

Manufacturing & testing flow (short version)

Material selection (NBR/FKM) → case phosphating → adhesive bonding → compression molding and vulcanization → flash trimming → precision grinding → spring assembly → 100% visual check → air-leak and lip torque testing.

Typical tests: leakage at 0.6 MPa; lip wear at 120°C/0.5 MPa/6 m/s; oil swell (ASTM D471); case corrosion (≥48 h NSS). Service life? Around 4,000–8,000 hours in mixed duty when shafts are within spec. I guess the big decider is oil cleanliness and shaft finish—surprisingly underrated.

Installation tips that save rework

• Use a lead-in chamfer 15–30°; deburr and polish the shaft.
• Pre-lube the primary lip; use a sleeve over keyways/threads.
• Press squarely on the outer case; never hammer the inner lip area.

Vendor snapshot (pricing is indicative)

Field feedback and mini case studies

- A rental fleet in Shaanxi swapped to the 28-40-5.5 Tcv Oil Seal High Pressure Oil Seal on excavator travel motors; average logged life moved to ~6,000 hours without oil misting. Actually, the bigger win was less cleanup around the hub.

- A road roller OEM reported ≈30% fewer warranty returns after switching to FKM for hot summer paving regions. Not magical—just better heat margin and lip stability.

Standards, data, and the fine print

• Design follows DIN 3760 / ISO 6194; elastomers per ASTM D2000; oil swell per ASTM D471.
• Typical leakage target: ≤0.3 mL/h at 0.6 MPa (lab bench, clean oil, new shaft).
• Service conditions vary; confirm shaft hardness, finish, and ventilation before pushing pressure peaks.

If you need custom lips (dust lip geometry, spring preload tweaks) or a high-temp FKM version, ask for a drawing sign-off—small changes here pay off big in uptime.

Authoritative citations

1. ISO 6194-1/2: Rotary shaft lip-type seals — Vocabulary, sizes and tolerances. https://www.iso.org
2. DIN 3760: Rotary shaft seals — Dimensions and requirements. https://www.din.de
3. ASTM D2000: Standard Classification System for Rubber Products. https://www.astm.org/d2000
4. ASTM D471: Standard Test Method for Rubber Property—Effect of Liquids. https://www.astm.org/d0471