AIINDUSTRY®

Rotary Seals — Reliable Barrier for Rotating Shafts & Dynamic Equipment

Designed for rotating shafts, pumps, gearboxes, and dynamic equipment. Covering five major categories — skeleton oil seals, PTFE rotary seals, V-rings, mechanical seals, and shaft repair sleeves. Full coverage from -200°C to 260°C, from low speed to 50 m/s high speed.

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Five Rotary Seal Categories

Full-spectrum rotating shaft sealing: contact & non-contact, axial & radial, low-speed heavy-load & high-speed light-load. Product lines cover TC/TB/SC series skeleton oil seals, PTFE spring-energized rotary seals (Variseal® design reference), V-ring axial seals, mechanical seals, and shaft repair sleeves. From general industry to extreme conditions, AIINDUSTRY® finds the optimal sealing solution for every rotating shaft.

Oil Side Air Side

Skeleton Oil Seal

Core MaterialNBR / FKM / VMQ
Temperature Range-60 ~ 200°C
Max Linear Speed≤20 m/s
Max Pressure≤0.05 MPa
Case MaterialRubber / Steel Shell
StandardISO 6194

Classic rotating shaft seal with L-shaped metal reinforcement case, rubber outer shell, and internal garter spring. The metal case provides radial rigidity for interference fit assembly, while the spring maintains stable radial contact force of the sealing lip on the shaft surface (lip interference 0.5–1.5 mm). Three standard configurations — TC (double-lip with spring), TB (single-lip with spring), SC (single-lip without spring) — cover diverse sealing requirements: TC full-protection for dusty environments, TB standard for clean oil lubrication, SC economical for low-speed grease. NBR general-purpose (-40~100°C), FKM high-temp chemical-resistant (-20~200°C), VMQ ultra-high-temp (-60~200°C). Rubber case for aluminum/cast iron housings, steel shell for steel housings with precision interference fit.

ISO 6194 · TC/TB/SC Types · Metal Case · Rubber/Steel Shell
PTFE Jacket + Spring-Energized

PTFE Rotary Seal

Core MaterialPTFE + Spring-Energized
Temperature Range-200 ~ 260°C
Max Linear Speed≤40 m/s
Max Pressure≤0.5 MPa
Spring MaterialStainless Steel / Elgiloy

PTFE jacket wrapped around a metal spring-energized structure. The spring provides continuous radial force to compensate for PTFE creep and wear. PTFE's extremely low friction coefficient (μ<0.05) enables ultra-high-speed rotation up to 40 m/s — far exceeding the 20 m/s ceiling of skeleton oil seals. -200~260°C wide temperature range with near-universal chemical resistance. Reference Trelleborg Variseal® design philosophy, with selectable U/V-shaped cross-section, stainless steel or Elgiloy spring-energizer providing long-term stable radial contact force. The preferred solution for compressors, high-speed spindles, aero-engines, and other extreme rotating shaft sealing applications where skeleton oil seals cannot perform.

Wide Temperature Range · Ultra-Low Friction · Ultra-High Speed · Variseal® Grade
Axial Seal — Dust/Water Protection

V-Ring

Core MaterialNBR / FKM / VMQ
Temperature Range-60 ~ 200°C
Max Linear Speed≤12 m/s
Sealing DirectionAxial Seal

V-shaped cross-section all-rubber axial seal. Elastically tensioned onto the shaft and rotates with it. Under centrifugal force, the V-shaped lip opens and presses against the counter face to achieve axial sealing — zero axial thrust when static, centrifugal boost when dynamic. No groove machining required on the shaft — simply slip on and use. Primarily used as an auxiliary dust and water protection barrier for main shaft oil seals, installed on the outer face of bearing housings to effectively block mud, dust, and cleaning fluids. NBR standard, FKM high-temp, VMQ cryogenic — three material grades covering different temperature zones. Maximum axial runout compensation: 2–3 mm.

Axial Sealing · Dust/Water Protection · No Contact Wear · Groove-Free Installation
SiC C Fluid Film Thickness ≈ 1μm

Mechanical Seal

Core MaterialSiC / Carbon-Graphite + FFKM
Temperature Range-40 ~ 200°C
Max Linear Speed≤50 m/s
Max Pressure≤5 MPa
Face MaterialsSiC / Carbon-Graphite / WC

Two ultra-precision flat faces — a stationary ring and a rotating ring — mate under spring force and fluid pressure, forming an approximately 1 μm fluid film for non-contact sealing. This ensures sealing effectiveness while avoiding dry friction and face burnout. The classic SiC vs. carbon-graphite friction pair is wear and corrosion-resistant; tungsten carbide (WC) vs. SiC is used for particle-laden media. FFKM secondary seals ensure reliable sealing across the full temperature range (-40~200°C). Zero leakage, high reliability, long service life (typical MTBF >25,000 hours). The core sealing solution for pumps, compressors, agitators, and reactors. Available in single, double, and tandem arrangements.

Zero Leakage · High Reliability · Non-Contact Seal · MTBF >25,000h
Repair Sleeve Wear Groove Stainless Steel Material

Shaft Repair Sleeve

Core MaterialStainless Steel
ApplicationRapid Shaft Wear Repair
Wall Thickness≤1.0 mm

Ultra-thin-wall stainless steel sleeve (wall thickness 0.25–1.0 mm). Quickly installed over the worn shaft area without disassembling the equipment, providing a new smooth sealing counterface (Ra ≤ 0.2 μm) for the oil seal lip. Installation kit includes a dedicated tool and guide cone — single-operator installation in 15 minutes. The extremely thin wall does not affect the existing seal specification selection, allowing continued use with standard TC/TB/SC skeleton oil seals. Saves over 80% of downtime and repair costs compared to shaft replacement or weld build-up. Stainless steel is corrosion-resistant with surface hardness up to HV300+, extending the shaft surface service life after repair.

Rapid Repair · 15-Minute Installation · Stainless Steel · Downtime Cost Savings

Oil Seal Selection Decision Tree

Quickly determine the appropriate rotary seal solution based on five key parameters: shaft diameter, rotational speed, temperature, media, and installation space. TC/TB/SC are the three standard skeleton oil seal configurations.

Decision CriteriaIndicatorRecommended SolutionEngineering Basis
Shaft Dia. & Speedd ≤ 100 mm, v ≤ 20 m/sTC/TB Skeleton Oil Seal (NBR)Standard small-to-medium shaft rotary sealing. NBR lip maintains stable oil film up to 20 m/s. TC double-lip for dust protection, TB single-lip economical. Above 20 m/s: upgrade to PTFE rotary seal.
Operating Temp.T ≤ 200°CSkeleton Oil Seal (FKM/VMQ) or PTFE Rotary SealNBR general-purpose below 100°C. FKM (fluorocarbon) or VMQ (silicone) for 100–200°C. Above 200°C: PTFE rotary seal required (max 260°C). Variseal®-type PTFE maintains stable radial force over wide temperature range.
Media TypeMineral / Synthetic / ChemicalMineral Oil→NBR
Synthetic Oil→FKM
Chemicals→PTFE
NBR has best mineral oil compatibility. FKM (fluorocarbon) resists synthetic oils, phosphate esters. PTFE is fully chemically inert for aggressive chemicals. Mechanical seals for strict zero-leakage requirements.
Installation SpaceLimited axial/radial spaceSingle-Lip SC Skeleton Oil Seal or V-Ring Axial SealSC type has no spring attachment, minimal axial dimension, suitable for grease-lubricated slow rotation. V-ring is purely axial sealing, occupies no radial housing space, slips directly onto the shaft.
Leakage Rate Req.Zero / Trace Leakage AcceptableZero Leak→Mechanical Seal
Trace→Skeleton Oil Seal/PTFE Seal
Mechanical seal fluid film achieves zero visible leakage (<5 mL/h) for pumps, compressors. Skeleton oil seals and PTFE rotary seals allow trace oil film pass-through (<0.1 g/h); pair with V-ring dust protection to extend maintenance intervals.

PTFE Rotary Seal vs. Skeleton Oil Seal

Comprehensive comparison across speed, temperature, pressure, service life, and cost. Variseal®-grade PTFE rotary seals are the preferred solution for high-performance applications.

DimensionPTFE Rotary Seal (Variseal® Type)Skeleton Oil Seal (TC/TB/SC Types)Recommendation
Max Speed≤ 40 m/s≤ 20 m/sHigh-speed (>20 m/s) requires PTFE rotary seal. Rubber lip accumulates frictional heat at high speeds leading to premature failure.
Temperature-200 ~ 260°C-60 ~ 200°CPTFE seal has no rival in wide temperature range (-200~260°C). Skeleton oil seals cover 85% of industrial applications within -60~200°C.
Pressure≤ 0.5 MPa≤ 0.05 MPaPTFE rotary seal has 10× the pressure capacity of skeleton oil seals, suitable for back-pressure rotary sealing applications.
Service Life> 10,000 h3,000 ~ 8,000 hPTFE seal's extremely low friction coefficient (μ<0.05) yields far lower wear rate than rubber oil seals. Over the lifecycle, PTFE seals offer advantages in equipment with long overhaul intervals.
Unit CostHigherLowSkeleton oil seals have significant cost advantage for high-volume standard applications. PTFE rotary seals have higher unit cost but may offer better lifecycle value. Evaluate based on MTBF requirements.

Complete Specification Datasheet

The full rotary seal specification datasheet includes groove dimensional tolerances, material property comparisons, lip interference recommendations, and installation process requirements. Supports quick search by shaft series, temperature grade, speed range, and media type.

Download Specification Datasheet (PDF)

More Sealing Categories

Explore other AIINDUSTRY® sealing categories for a complete sealing solution.

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