Oil and Abrasion Resistant Hardness 70NBR Buna Nitrile Rubber O-Ring for Automotive

Oil and Abrasion Resistant Hardness 70NBR Buna Nitrile Rubber O-Ring for Automotive

70 Shore A NBR (Buna-N) Nitrile Rubber O-Ring for automotive. Excellent resistance to engine oil, grease & fuel. AS568 /metric sizes, compression molded auto O-rings for engine, transmission, power steering & fuel system seals.

We supply standard sizes following AS568, ISO3601, DIN3771, JIS B2401, as well as custom-molded O-rings with custom ID, OD and cross-section. Hardness options range from 40 ~ 90 Shore A; 70 Shore A black NBR is our most popular stock grade

Product Specifications

O-Ring Specific Tolerance Table

This sheet covers dimensional tolerance specifications for both custom molded and standard O‑rings, including inner diameter and cross‑section.

We set tolerance grades in accordance with ISO 3302‑1. For O‑rings with an inner diameter exceeding 670 mm, the tolerance is 0.64% of the inner diameter. Multiple precision classes are available to suit general industrial, hydraulic and high‑demand sealing applications.

All tolerance documentation can be supplied for your incoming inspection, supplier audits and drawing reference. Tighter tolerances can be negotiated for special high‑precision projects

.

Rubber material date sheet:

We can provide complete physical test reports according to your material requirements, including hardness, tensile strength, elongation, compression set, temperature range and chemical resistance.

We are able to supply COA, COC and compliance documents for REACH, RoHS, FDA and UL. Batch traceability is guaranteed for custom molded sealing parts

Your Trusted Supplier of Molded Rubber Products

Xiamen Lead Rubber & Plastic Industry Co., Ltd. is a professional factory focused on the design and fabrication of rubber & plastic molds, as well as custom molded rubber and plastic components.

We specialize in exporting O-rings, rubber gaskets, various rubber seals, rubber bumpers, molded plastic parts, precision tooling molds and other custom molded products.

Our in-house mold workshop develops custom molds for a wide range of rubber and plastic materials. We design and manufacture tooling strictly according to customers’ 2D/3D drawings, samples and technical specifications.

We provide full one-stop OEM & ODM solutions for global buyers, covering mold development, material formulation, prototyping, mass production and quality inspection. Our products widely serve automotive, hydraulic, pneumatic and general industrial sealing applications.

Custom rubber oring /gasket seal  Manufacturing

Lead Rubber is a professional manufacturer specializing in custom molded rubber sealing components and mold fabrication.

We mainly export custom rubber O-rings, gaskets, various rubber seals, rubber bumpers, precision molds and other custom molded rubber & plastic parts.

We develop custom molds for a wide range of rubber and plastic materials based on customers’ drawings, samples and technical requirements. We deliver one-stop OEM & ODM custom sealing solutions for global buyers.

OEM Services and Mold Development

Lead rubber  offers full OEM development for custom molded rubber O-rings, gaskets and seals, plus custom plastic components.

Following your drawings, samples or technical specifications, we manufacture tailored sealing parts with our in-house mold workshop covering mold design, CNC machining, trial testing and validation.

We support multiple materials including NBR, EPDM, FKM, Silicone and engineered plastics. Our engineering team collaborates with you for prototype sampling and mass production tooling to balance quality, lead time and cost.

Quality Control and Testing for rubber oring

Lead rubber enforces strict QC throughout rubber O-ring manufacturing, from raw material incoming check to finished goods inspection before shipment.

Our laboratory is equipped with hardness tester, projector, micrometer, compression set tester and tensile tester. We conduct visual inspection, dimensional measurement, Shore A hardness, compression set and tensile strength tests.

Material certificates and batch inspection reports are available upon request to guarantee consistent sealing performance.

Packaging and Delivery Preparation

Lead Rubber offers packaging options for international shipments, including PE bags, export carton, and palletized packaging where required. Customized packaging, logo printing, and product labeling can be discussed according to order quantity and customer requirements.

Packaging methods are selected according to the product type, shipment method, and destination requirements. Please confirm any special packaging or labeling instructions before placing an order.

Frequently Asked Questions

Q1: What is a rubber O-ring?

A: A rubber O-ring is a circular elastomer seal used for static and dynamic sealing to prevent liquid or gas leakage.

Q2: What materials do you offer for rubber O-rings?

A: Main materials: NBR, EPDM, FKM(Viton), Silicone(VMQ), HNBR, CR(Neoprene). We recommend material according to your working media, temperature and pressure.

Q3: What is the common hardness of rubber O-rings?

A: Hardness ranges from 20~90 Shore A. 70 Shore A NBR is the most popular grade for general sealing.

Q4: What size standards are available?

A: AS568 imperial sizes and metric sizes in stock. Custom ID, OD and cross-section O-rings are also available via OEM molding.

Q5: What temperature range can NBR O-rings withstand?

A: NBR O-rings work from -40°C to 120°C continuous service. Peak short-time temperature up to 120°C.

Q6: Can you make custom rubber O-rings?

A: Yes. We provide OEM ODM custom O-rings. Please offer drawings, samples or dimension specifications for quotation.

Q7: What tests do you perform on rubber O-rings?

A: We carry out visual inspection, dimensional check, Shore hardness, tensile strength and compression set test with professional testing equipment. COA and inspection reports can be provided.

Q8: What industries use rubber O-rings?

A: Widely used in automotive, hydraulic, pneumatic, machinery, pump, valve and agricultural equipment.

Q9: What information should I provide for quotation?

A: Material, hardness, ID/OD/cross-section, quantity, working condition (temperature, media, pressure) and application.

Q10: What is your MOQ?

A: Standard O-rings accept small orders. Custom molded O-rings depend on mold cost and product size, we support prototype and mass production.

Request a Quote for rubber oring

Looking for standard or custom rubber O-rings, gaskets and molded rubber seals for automotive & industrial applications? Contact Lead Rubber with your specifications.

Please submit 2D/3D CAD drawings or physical samples, dimensions, rubber material, hardness, quantity, application and special performance requirements for quotation. If custom mold tooling is needed, also advise cavity quantity and mold steel preferences.

Contact Person: Sunny                              
Tel: 0086-13400616316   
WhatsApp: 0086-13400616316
Email: sales1@leadindustryproducts.com

Contact Person: Lucy

Tel: 0086-13328793979

WhatsApp: 0086-13328793979

Email: sales4@leadindustryproducts.com

Contact Person: Nana

Tel: 0086-15872688050

WhatsApp: 0086-15872688050

Email: sales2@leadindustryproducts.com

Pricing Notice: The displayed price is for reference only. The final quotation depends on product design, material selection, dimensions, tooling requirements, order quantity, surface treatment where applicable, and packaging specifications.