Custom rubber sealing gaskets serve as critical components in industrial equipment, automotive, medical devices, and other fields, directly impacting system sealing performance, weather resistance, and service life. By precisely matching rubber material properties with sealing application requirements and integrating advanced molding technologies with customized processes, we provide a full-process solution from material selection to mass production, meeting diverse needs for sealing gaskets in complex environments such as high-pressure, high-temperature, and corrosive conditions.
Custom Rubber Sealing Gaskets

I. Core Material Properties and Application Advantages

(A) Comparison of Mainstream Material Properties

Material Type
Density (g/cm³)
Temperature Range (℃)
Shore A Hardness
Chemical Resistance (Typical Media)
Core Advantages
Typical Certifications
Nitrile Butadiene Rubber (NBR)
1.2–1.4
-40~120
40–90
Mineral oil, hydraulic oil
Excellent oil resistance, high elasticity
ISO 16232 Automotive Certification
Silicone Rubber (SIL)
1.1–1.3
-60~200
20–80
Extreme temperature, weathering
Non-toxic, electrical insulation, environmental friendly
FDA Food Contact Certification
Fluorine Rubber (FKM)
1.8–2.0
-20~250
60–90
Strong acid, alkali, fuel oil
Excellent high-temperature and chemical resistance
ASTM D2000 Performance Certification
Ethylene Propylene Diene Monomer (EPDM)
0.9–1.1
-50~150
40–80
Water vapor, UV radiation
Outstanding weather and aging resistance
EN 681-1 Sealing Standard Certification
Hydrogenated Nitrile Butadiene Rubber (HNBR)
1.2–1.3
-30~150
50–90
Ozone, high-pressure oil
High strength, low-temperature impact resistance
IATF 16949 System Certification

(B) Driving Forces of Customization Requirements

1. Sealing Performance Requirements

  • Pressure Resistance: Static sealing pressure ≥10MPa (hydraulic systems), dynamic sealing pressure ≥5MPa (rotating shaft seals).
  • Leakage Rate: Helium mass spectrometer detection, leakage ≤1×10⁻⁹ mbar·L/s (high-vacuum environments).
  • Compression Set: 150℃×22h test, deformation rate ≤20% (GB/T 7759.1 standard).

2. Environmental Adaptability

  • Thermal Shock Resistance: -40℃~120℃ cycling 50 times, hardness change ≤±5 Shore A.
  • Weather Resistance: QUV-A aging test for 1000 hours, cracking grade ≤1 (GB/T 16422.3).
  • Chemical Resistance: Immersion in 10% sulfuric acid/sodium hydroxide for 72 hours, volume change rate ≤5%.

3. Structural Adaptability

  • Dimensional Accuracy: Inner/outer diameter tolerance ±0.1mm, thickness tolerance ±0.05mm (GB/T 3452.1 standard).
  • Surface Roughness: Sealing surface Ra≤1.6μm to reduce micro-leakage paths.

II. Analysis of Four Core Processing Technologies

(A) Compression Molding: High-Precision Seal Processing

  • Technical Advantages
    • Enables one-step molding of complex sections such as O-rings and flange gaskets, dimensional accuracy ±0.05mm.
    • Multi-cavity design (8–32 cavities per mold), production efficiency 500–2000 pieces/hour, compatible with GB, ASME, JIS standards.
  • Process Parameters
    • Vulcanization temperature 150–200℃, pressure 10–30MPa, vulcanization time 3–10 minutes (adjusted by thickness).
    • Mold surface roughness Ra≤0.8μm to ensure sealing surface smoothness.

(B) Injection Molding: Automated Mass Production

Process Type
Typical Application Scenarios
Technical Highlights
Cold Runner Injection
High-precision O-rings
Material utilization ≥95%, flash thickness ≤0.05mm
Liquid Silicone Rubber (LSR) Injection
Medical-grade seals
Cleanroom production (Class 100,000), compliant with ISO 13485 standard
  • Technical Advantages
    • Fully automated production line integrates material to finished product, defect rate ≤0.3%.
    • Supports thin-wall design (thickness ≥0.5mm) for micro-seal precision requirements.

(C) Extrusion Molding: Custom Long Sealing Parts

  • Process Advantages
    • Suitable for continuous seals like weather strips and rubber hoses, length error ≤0.1%.
    • Multi-layer co-extrusion technology combines wear-resistant/oil-resistant layers, extending life by 30%.
  • Key Parameters
    • Extrusion speed 5–15m/min, temperature control accuracy ±2℃.
    • Cross-sectional dimension tolerance ±0.2mm, adaptable to complex sealing structures.

(D) Secondary Processing: Functional Enhancement

  • Surface Modification
    • PTFE coating: Friction coefficient reduced by 40% (to <0.15), suitable for high-speed rotating seals.
    • Conductive coating: Surface resistance ≤10⁶Ω to prevent static accumulation (electronic device sealing).
  • Structural Optimization
    • Metal skeleton embedding: Tensile strength increased by 50%, suitable for high-pressure applications (e.g., hydraulic cylinder seals).
    • Lip chamfer design: Sealing lip angle 30°±5°, contact pressure uniformity improved by 20%.

III. Full-Process Customization Solutions

(A) Design and Material Engineering

1. Multi-Dimensional Design Support

  • Structural Optimization
    • FEA simulation of sealing surface pressure distribution ensures contact stress ≥3MPa (leakage critical value).
    • Lip seal lip thickness designed at 1.5–2.5mm, dynamic sealing life ≥1000 hours (GB/T 13871.4 standard).
  • Functional Customization
    • Self-lubricating gaskets: Embedded molybdenum disulfide particles, friction power consumption reduced by 30% (high-speed equipment).
    • Smart monitoring seals: Integrated pressure sensor slots, accuracy ±1%FS (industrial IoT scenarios).
  • Tolerance Design
    • Static seal compression rate controlled at 15%–30%, dynamic seal fit clearance ≤0.1mm (per GB/T 20082 standard).

2. Precise Material Selection

  • Automotive Engine Sealing: FKM material, resistant to 150℃ high temperature and fuel erosion, compliant with SAE J2005 standard.
  • Drinking Water Systems: SIL material, NSF 61 certified, heavy metal leaching ≤0.1ppm.
  • High-Pressure Hydraulic Systems: HNBR material, tear strength ≥25kN/m, suitable for -30℃~120℃ conditions.

3. Pre-Processing Technology

  • Raw material mixing: Twin-screw extruder mixing uniformity ≥98% to ensure consistent vulcanization performance.
  • Mold pre-treatment: Teflon release agent coating reduces demolding force by 50%, minimizing surface defects.

(B) Production and Quality Control

1. Flexible Manufacturing Capability

  • Rapid Prototyping
    • 3D printed silicone samples delivered in 24 hours, mold development cycle 7–15 days (simple mold).
    • Supports minimum order quantity of 100 pieces for small-to-medium batch customization.
  • Mass Production
    • Intelligent production lines: Equipped with visual inspection robots, dimensional detection accuracy ±0.03mm, defect recognition rate ≥99.5%.
    • Capacity: 100,000 pieces/day for standard O-rings (compression molding), 50,000 pieces/day for medical-grade seals (LSR injection).

2. Comprehensive Inspection System

  • Sealing Performance
    • Water pressure test: 1.5x rated pressure for 30 minutes, pressure drop ≤1% (GB/T 14153 standard).
    • Air tightness test: 50kPa pressure maintained for 10 minutes, leakage ≤5ml/min.
  • Physical Properties
    • Tensile strength/elongation at break: Compliant with GB/T 528, test accuracy ±2%.
    • Hardness test: Shore durometer detection, tolerance ±2 Shore A (GB/T 531.1 standard).
  • Environmental Performance
    • Oil resistance test: Immersion in ASTM No.3 oil at 70℃×168h, volume change rate ≤10%.
    • Fire resistance test: Oxygen index ≥28%, compliant with UL94 HB (special application requirements).
  • Certification Support: Provides FDA, RoHS, IATF 16949, and other certification reports for global market access.

IV. Multi-Scenario Application Solutions

(A) Industrial Equipment Sector

  • Valve Sealing Gaskets: EPDM material, resistant to water vapor (150℃×1000h no aging), suitable for DN50–DN1000 flange specifications.
  • Compressor Seals: HNBR material, high-pressure resistance (20MPa) and ozone resistance (50pphm×100h no cracking), used in refrigeration equipment.

(B) Automotive Industry

  • Engine Oil Pan Sealing: FKM + metal skeleton, resistant to 180℃ high temperature and engine oil, leakage rate ≤5×10⁻⁸ mbar·L/s.
  • New Energy Vehicle Battery Sealing: SIL material, resistant to electrolyte corrosion (pH 3–11), fire rating V-0 (UL94 standard).

(C) Medical Devices

  • Medical Pipeline Sealing: LSR liquid silicone rubber, ISO 10993 biocompatibility certified, extractables ≤0.01μg/ml.
  • Surgical Equipment Sealing: Transparent silicone material, light transmittance ≥90%, suitable for precision instruments like endoscopes.

(D) New Energy Sector

  • PV Inverter Sealing: EPDM + UV-resistant additives, weather resistance grade 4 (QUV-A 2000h color difference ΔE≤3), IP68 waterproof rating.
  • Fuel Cell Sealing: Perfluoroelastomer (FFKM), resistant to 200℃ high temperature and hydrogen permeation, compliant with ISO 21247 standard.

V. Technology Selection Guide

Requirement Type
Preferred Technology
Material Selection
Core Indicators
Delivery Cycle
High-Pressure Sealing
Compression Molding + FKM
Fluorine Rubber
250℃ resistance, 20MPa pressure tolerance
Prototype in 5 days, mass production in 25 days
Food & Medical Grade
LSR Injection + SIL
Silicone Rubber
Non-toxic certification, biocompatibility
Prototype in 7 days, mass production in 30 days
Large-Scale Standard Production
Injection Molding + NBR
Nitrile Rubber
Oil resistance, cost-effective
Prototype in 5 days, mass production in 20 days
Weather & Aging Resistance
Extrusion Molding + EPDM
EPDM Rubber
UV resistance, water vapor resistance
Prototype in 6 days, mass production in 22 days
Custom rubber sealing gaskets achieve full-category coverage from 0.5mm micro O-rings to 1000mm large flange gaskets through deep integration of material properties, processing technologies, and sealing applications. Whether in high-pressure industrial environments or clean medical scenarios, our full-process technical capabilities ensure each customized solution meets precise standards for sealing performance, durability, and environmental adaptability.
For custom solutions using NBR/SIL/FKM materials, certification processes, or production capacity data, contact us for professional support from design development to mass production.

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