What is an NBR O Ring?

NBR O Rings, also known as Buna-N O Rings, are among the most commonly used sealing elastomers in various industries. Their popularity stems from their exceptional resistance to petroleum-based fuels and lubricants. Made from nitrile rubber, which is a copolymer of acrylonitrile and butadiene, these O Rings offer a balance of performance and cost-effectiveness.

Importance in various industries

NBR O Rings play a pivotal role in numerous applications, from automotive to aerospace, from healthcare to heavy machinery. Their ability to provide a reliable seal ensures the smooth operation of equipment and machinery, preventing leaks and ensuring the safety of both the equipment and its operators. Given the diverse range of applications, it’s no surprise that the demand for high-quality NBR O Rings, such as those provided by Suzhou Baoshida Rubber, remains consistently high.

Basic Characteristics of NBR O Rings

Resistance to petroleum-based fuels and lubricants

One of the standout features of NBR O Rings is their resistance to oils and fuels. This makes them an ideal choice for applications where they might come into contact with such substances. Whether it’s in an engine, a fuel pump, or industrial machinery, the NBR O Ring ensures that there are no leaks, leading to efficient operation and reduced maintenance costs.

Cost-effectiveness and widespread use

NBR O Rings are not just known for their performance but also for their cost-effectiveness. They offer a reliable sealing solution without breaking the bank. This affordability, combined with their robust performance, has led to their widespread use across various industries. From automotive to oil and gas, from food processing to pharmaceuticals, NBR O Rings have found a place everywhere.

Suzhou Baoshida Rubber: Leading NBR O Ring Supplier in China

Company overview and history

Suzhou Baoshida Rubber, located in Suzhou, Anhui Province, China, has been a trusted name in the rubber industry since 2007. With a focus on producing high-quality rubber seals and products, the company has established itself as a leading supplier in the market. Their team of experienced engineers and dedicated workers ensures that every product meets the highest standards of quality.

Commitment to quality and customer satisfaction

At Suzhou Baoshida Rubber, customer satisfaction is paramount. The company provides OEM services for rubber products and power tools, ensuring that every product is tailored to meet the specific needs of the customer. With more than 10 partner factories in China, Suzhou Baoshida Rubber guarantees timely delivery and top-notch products.

Production Process

How NBR O Rings are made

The production of NBR O Rings involves a series of steps, starting with the selection of the right raw materials. The acrylonitrile content in the polymer chains can vary, affecting the properties of the final product. Once the materials are selected, they undergo a curing process, which can be either sulfur-cured or peroxide-cured, each having its own set of advantages.

Quality control measures at Suzhou Baoshida Rubber

Quality is non-negotiable at Suzhou Baoshida Rubber. From the initial stages of production to the final product, rigorous quality checks are in place. The company’s commitment to excellence ensures that every NBR O Ring that leaves their factory is of the highest standard.

Choosing the Right NBR O Ring

Factors to consider: size, application, environment

When selecting the right NBR O Ring for a specific application, several factors come into play. The size of the O Ring is crucial, as it needs to fit perfectly to ensure a proper seal. Additionally, the specific application and the environment in which the O Ring will be used are also vital considerations. For instance, an O Ring used in a high-temperature setting might require different properties than one used in a colder environment.

Custom solutions from Suzhou Baoshida Rubber

Understanding that every application might have unique requirements, Suzhou Baoshida Rubber offers custom solutions to its clients. Whether it’s a specific size, a unique blend of materials, or any other customization, the company’s expertise ensures that clients get an O Ring tailored to their needs.

Questions International Buyers Should Ask Chinese Suppliers

Quality certifications and standards

For international buyers, understanding the quality standards adhered to by the supplier is crucial. It’s essential to ask about the certifications the supplier holds and the quality standards they follow. This ensures that the products received are of the highest quality and meet international standards.

Lead times and shipping considerations

Another critical aspect for international buyers is the lead time for production and shipping. Understanding how long it will take for the products to be produced and shipped can help in planning and inventory management.

Customization capabilities

Given that every application might have unique requirements, understanding the customization capabilities of the supplier is essential. This ensures that the products received are tailored to the specific needs of the application.


  1. What is the temperature range for NBR O Rings from Suzhou Baoshida Rubber?
    • Answer: Depending on the specific type and curing process, the temperature range can vary. However, typical ranges are from -35°C to 120°C for sulfur-cured and -29°C to 135°C for peroxide-cured.
  2. How does the acrylonitrile content affect the properties of NBR O Rings?
    • Answer: The acrylonitrile content can vary from 18% to 50%. Lower ACN content provides better low-temperature properties but lesser resistance to fuels and lubricants. Higher ACN content offers improved resistance but inferior low-temperature properties.
  3. Can I get a custom-sized NBR O Ring from Suzhou Baoshida Rubber?
    • Answer: Yes, Suzhou Baoshida Rubber offers customization options, ensuring that clients get O Rings tailored to their specific requirements.

Preferred Environments for NBR O Rings

Performs Well In:

NBR O Rings are versatile and can function effectively in a variety of environments. Some of the conditions where they excel include:

  • Petroleum-based oils and fuels: Their inherent resistance to these substances makes them ideal for automotive and industrial applications.
  • Aliphatic hydrocarbons: These are common in many industrial processes, and NBR O Rings can handle them with ease.
  • Vegetable oils: In the food industry, where vegetable oils are prevalent, NBR O Rings are often the seal of choice.
  • Silicone oils and greases: These are used in various applications, from automotive to aerospace, and NBR O Rings can resist them effectively.
  • Ethylene glycol: Commonly found in antifreeze, NBR O Rings can withstand this substance without degrading.
  • Dilute acids: In mild acidic environments, NBR O Rings can provide a reliable seal.
  • Water up to 100ºC (212ºF): For hot water applications, NBR O Rings are often preferred.

Doesn’t Perform Well In:

While NBR O Rings are versatile, there are certain environments where they might not be the best choice:

  • Aromatic hydrocarbons: These can degrade the NBR material over time.
  • Automotive brake fluid: This fluid can cause NBR O Rings to swell or degrade.
  • Chlorinated hydrocarbons, ketones, ethers, and esters: These chemicals can adversely affect NBR O Rings.
  • Phosphate ester hydraulic fluids: Common in some industrial applications, these fluids can degrade NBR.
  • Strong acids: In highly acidic environments, NBR might not provide a reliable seal.
  • Ozone, weathering, and sunlight: Prolonged exposure to these can cause NBR O Rings to degrade over time.


NBR O Rings, with their versatility and cost-effectiveness, have become an integral part of many industries. Whether it’s in the automotive sector, the food industry, or heavy machinery, these seals ensure smooth operations and prevent costly leaks. For those looking for high-quality NBR O Rings, Suzhou Baoshida Rubber stands out as a trusted supplier. With their commitment to quality, customization capabilities, and a deep understanding of the needs of international buyers, they are a go-to choice for many businesses worldwide.