# Special Waterproof Sealing Ring for Smart Door Locks: LSR Weather-resistant Sealing Part
Product Overview
The Special Waterproof Sealing Ring for Smart Door Locks is a high-precision liquid silicone rubber (LSR) component engineered to solve the core durability challenges of smart access control devices exposed to variable outdoor and indoor environmental conditions. As a critical barrier between the smart lock’s internal electronic components (circuit boards, biometric sensors, battery compartments, and motor drives) and external contaminants, this sealing part delivers reliable long-term protection against water ingress, dust, temperature fluctuations, and UV radiation, directly extending the service life of smart door locks by 3–5 years on average.
Manufactured via precision injection molding with medical and industrial-grade LSR raw materials, this sealing ring features a custom contoured profile tailored to match the assembly gaps of mainstream smart lock models, including deadbolt, mortise, rim, and biometric fingerprint locks. Unlike traditional EPDM or neoprene seals, it combines exceptional weather resistance, consistent compression set performance, and food-safe non-toxicity, making it suitable for both residential, commercial, and industrial smart lock deployments. Its key selling points include IP67-rated waterproof performance when properly installed, 10+ year resistance to outdoor aging, zero leakage under 1.5m water immersion for 30 minutes, and compatibility with automated high-volume lock assembly lines.
Technical Specifications
Material Properties
All LSR raw materials for this sealing ring comply with global environmental and safety standards, with customizable formulations for specific application scenarios:
ParameterStandard GradeUV-resistant Outdoor GradeLow-temperature Arctic Grade
LSR Shore Hardness40–50 Shore A45–55 Shore A35–45 Shore A
Raw Material Purity100% food-grade LSR, no plasticizers or heavy metals100% industrial-grade LSR with UV stabilizers100% low-temperature modified LSR
Chemical ResistanceResistant to weak acids, weak alkalis, common household detergents, and salt sprayResistant to acid rain, automotive exhaust, and 5% NaCl salt sprayResistant to road deicing salts and hydraulic oils
Toxicity ComplianceRoHS 2.0, REACH (SVHC 224 items), FDA 21 CFR 177.2600RoHS 2.0, REACH, CE EN 50130-4 for security equipmentRoHS 2.0, REACH, IEC 60068-2-1 for low-temperature operation
Flame RetardancyUL94 HB (default)UL94 V-0 (optional)UL94 HB (default)
Physical Performance
The sealing part’s physical properties are tested per international sealing component standards to ensure consistent performance across its service life:
ParameterTest ConditionValue
Waterproof RatingIEC 60529 standardIP67 (IP68 optional for high-humidity coastal areas)
Compression Set22 hours at 70°C, 25% compression≤8% (far below the 20% industry threshold for long-term sealing)
Operating Temperature RangeContinuous operation-40°C to +120°C (-40°F to 248°F); extended to -55°C for arctic grade
Tensile StrengthASTM D412≥7.5 MPa
Elongation at BreakASTM D412≥550%
Tear ResistanceASTM D624 Die B≥18 kN/m
UV Aging Resistance1000 hours of UVB 313nm exposureNo cracking, hardness change ≤2 Shore A, color change ≤ΔE 3
Salt Spray Resistance5% NaCl solution, 35°C, 1000 hoursNo corrosion, no sealing performance degradation
Cycle Life10,000 door open/close cycles (compression/release)Sealing performance remains unchanged, no permanent deformation
Process Parameters
This sealing ring is designed for high-efficiency manufacturing and assembly, with parameters optimized to reduce production costs for smart lock brands:
ParameterValue
Molding Tolerance±0.03mm for critical sealing surfaces, ±0.05mm for assembly edges, meeting ISO 3302-1 Class M1 precision requirements
Flash Control≤0.02mm, no secondary deflashing required for standard models
Recommended Assembly Compression15–25% (20% optimal for balance of sealing performance and assembly force)
Maximum Assembly SpeedCompatible with 60 pieces/min automated assembly lines, no deformation under robotic pick-and-place operations
Adhesion CompatibilityBonds firmly with common lock housing materials (ABS, PC, zinc alloy, aluminum alloy) via room-temperature silicone adhesive or double-sided acrylic tape (pre-applied adhesive option available)
Shelf Life2 years when stored in a cool, dry environment (15–25°C, 40–60% RH) away from direct sunlight
Product Advantages
1. Industry-leading Weather Resistance for All Climates
Unlike EPDM seals that harden and crack after 3–5 years of outdoor UV exposure, this LSR sealing ring retains its elasticity and sealing performance for 10+ years under direct sunlight, heavy rain, and temperature extremes. It is tested to withstand 1000 hours of accelerated UV aging equivalent to 10 years of outdoor use in subtropical regions, and 1000 hours of salt spray testing without degradation, making it suitable for coastal, desert, and cold climate deployments where traditional seals fail prematurely.
2. Ultra-low Compression Set for Long-term Sealing Reliability
With a compression set of ≤8% at 70°C, the sealing ring maintains consistent contact pressure against the lock housing even after years of repeated compression from door operation. This eliminates the common problem of seal shrinkage or permanent deformation that leads to water ingress and lock failure after 2–3 years of use, reducing post-sales warranty claims for smart lock brands by up to 70%.
3. Precision Molding for Zero-leakage Fit
Manufactured with high-precision steel molds and closed-loop injection molding systems, every sealing ring has a uniform cross-section and consistent dimensions, with a tolerance of ±0.03mm on critical sealing surfaces. This ensures a perfect fit with the unique groove profiles of different smart lock models, eliminating gaps that cause water leakage even under high-pressure water spray (e.g., pressure washing of exterior doors) or heavy rainstorms.
4. Non-conductive, Sensor-safe Material Formulation
The LSR material is 100% non-conductive and free of corrosive additives, preventing short circuits to internal lock electronics and avoiding interference with biometric fingerprint sensors, NFC modules, and Wi-Fi antennas. Unlike PVC or rubber seals that leach plasticizers over time, this LSR part does not leave residue on sensor surfaces, ensuring consistent biometric recognition accuracy throughout the lock’s service life.
Applications
This LSR sealing ring is designed for all types of smart door locks, with custom sizes available for specific use cases:
- Residential Smart Deadbolts and Mortise Locks: Seals the front panel, fingerprint sensor cavity, and battery compartment of home smart locks, protecting against rain, dust, and insect intrusion for entry doors, balcony doors, and garage access points.
- Commercial and Office Smart Access Control Locks: Suitable for high-traffic office building entrances, hotel room locks, and co-working space access systems, with optional UL94 V-0 flame retardant grade for compliance with commercial building fire safety codes.
- Outdoor and Public Area Smart Locks: Ideal for gate locks, storage unit locks, community access control systems, and rental property smart locks, with the UV-resistant grade recommended for prolonged direct sunlight exposure, and IP68 optional grade for coastal areas with high humidity and salt spray.
- Special Environment Smart Locks: The low-temperature arctic grade is designed for cold storage facility locks, polar research station access systems, and smart locks used in regions with winter temperatures below -40°C, maintaining elasticity and sealing performance even in extreme cold.
- Custom Sealing Solutions: We also offer custom contoured seals for smart lock accessories, including keypad covers, card reader interfaces, and USB charging port plugs, to provide full-device waterproof protection.
Selection Guide
Hardness Selection
- 35–40 Shore A: Recommended for locks with irregular housing surfaces or low assembly force requirements, as the softer material conforms better to minor gaps. Suitable for indoor smart locks with low exposure to mechanical wear.
- 40–50 Shore A (Default): The universal grade suitable for 90% of smart lock applications, balancing elasticity, wear resistance, and sealing performance for both indoor and general outdoor use.
- 45–55 Shore A: Recommended for high-traffic commercial locks and outdoor locks exposed to strong wind and vibration, as the harder material resists displacement and wear from repeated door operation.
Size Specifications
We offer over 50 standard sizes matching mainstream smart lock models from leading global brands, including 60mm, 70mm, 80mm, and 90mm outer diameter circular seals, as well as rectangular and irregular contoured seals for special lock designs. Custom size and profile development is available for orders of 10,000 pieces or more, with free mold design support for large-volume long-term partners. When specifying a custom size, provide the groove width, depth, and required compression ratio to ensure optimal sealing performance.
Material Grade
- Standard Food-grade LSR: For residential and indoor locks, compliant with FDA and LFGB standards, non-toxic and odorless, suitable for homes with children and pets.
- UV-resistant Outdoor Grade: Added with 2% UV stabilizers and anti-aging agents, recommended for all outdoor locks and locks installed in areas with direct sunlight exposure.
- Low-temperature Arctic Grade: Modified LSR formulation with a glass transition temperature of -60°C, for locks operating in environments with temperatures below -30°C.
- Flame-retardant Grade: UL94 V-0 certified, for commercial and industrial locks required to meet building fire safety regulations.
Quality Assurance
Our LSR smart lock sealing rings are manufactured in an ISO 9001:2015 certified production facility, with a 5-stage quality control process to ensure zero defective products:
- Raw Material Inspection: Every batch of LSR raw material is tested for hardness, tensile strength, and compliance with RoHS and REACH standards before entering the production line.
- In-process Molding Inspection: 100% of products undergo dimensional inspection via high-precision coordinate measuring machines (CMM) every 30 minutes during production, with flash and surface defect checks for every 100 pieces.
- Performance Sampling Testing: For every production batch, 5% of samples undergo full performance testing, including IP67 waterproof verification, compression set testing, and UV aging testing, with test reports provided with each shipment.
- Pre-shipment Inspection: 100% of products undergo visual inspection for defects, and dimensional spot checks of 10% of the batch, before being packaged in anti-static EPE bags to avoid deformation during transportation.
- Warranty: We offer a 5-year quality warranty for all standard sealing rings, covering material defects, performance degradation, and sealing failure under normal use. Custom grade products come with a 3-year warranty, with free replacement for any confirmed quality issues.
All products hold CE, FCC, and RoHS certifications, with third-party test reports from SGS and Intertek available upon request, ensuring compliance with global smart lock safety and environmental regulations for North America, the European Union, and Asia-Pacific markets.
