sealing solution

Differentiation Through In-House Adhesive Development

One of NOK’s signature products, the oil seal, is typically made by combining rubber, a metal ring, and a spring. Adhesives are used to integrate these different materials into a single unit. However, bonding dissimilar materials such as rubber and metal is technically challenging, and oil seals must also perform reliably in demanding environments. For instance, they need to maintain adhesion while exhibiting heat and oil resistance, even at temperatures exceeding 100°C. To meet these stringent specifications, NOK has developed its own in-house adhesives for over 60 years.

NOK Adapts to Automotive Industry Changes with New Technologies

NOK's goal is to achieve consolidated sales of one trillion yen by FY2031, coinciding with its 90th anniversary. The automotive industry is undergoing a once-in-a-century transformation, and as a key supplier to the sector, NOK is evolving to handle these changes.
On May 22, 2024, at the Automotive Engineering Exposition 2024 held at Pacifico Yokohama, NOK showcased cutting-edge products and technologies to address critical societal challenges, including electrification and carbon neutrality (net zero greenhouse gas emissions). Earlier in April, the company introduced a unified corporate identity (CI) for its 92 Group companies worldwide, underscoring its commitment to innovation and collaboration. The exhibition featured standout technologies and products that reflect the Group's combined expertise.

Leveraging Material and Design Expertise to Ensure Safety and Reliability in Electric Vehicles

The advent of electric vehicles (xEVs) presents many new challenges, including thermal management and electromagnetic noise. Drawing on its expertise in material formulation and shape design gained while developing seal products, NOK offers a lineup of high-performance products tailored for electric vehicles, including a wide range of components and products to meet customer expectations. Senior Planner Junichi Watanabe and Masahiro Tanioka, manager of the NOK Group R&D Mobility Products Planning Department, shared insights into NOK’s offerings for electric vehicles.

The Foundation of Oil Seals: Dual Mechanisms for Lubrication and Sealing

Oil seals are designed to prevent leakage of oils, liquids and gases while also providing lubrication that ensures the smooth motion of components like rotating shafts and pistons, as well as low friction. Oil seals used in automobile engines and motors are also built to last for 10 years or 100,000 kilometers without replacement. But how do they maintain seal integrity, preventing the leakage of oil and ther fluids through the gap between roating or reciprocating components and the seal, while also sustaining low friction over time? It might seem almost too convenient, but the secret lies in the coexistence of two mechanisms: lubrication, which enables low friction, and sealing, which prevents leakage. This article will explain these mechanisms in detail.

Providing the Right Products for Advanced Technologies: NOK's Response to Automotive Electrification

NOK's largest customer, the automotive industry, is experiencing what is often called a once-in-a-century transformation. The spread of advanced technologies such as CASE (Connected, Autonomous, Shared, Electric) and the global imperative to achieve carbon neutrality (net zero greenhouse gas emissions) are demanding significant adaptive measures from the automotive sector. To keep pace with these rapid changes and ensure its survival, NOK must focus on developing products tailored to these themes.

Handling Opposing Functions: Oil Seals and Surface Design

A major independent automotive parts manufacturer highly regarded for its technical capabilities. NOK is a key supplier to all Japanese automakers. Its particular strength lies in oil seals, the product the company was founded to manufacture. Used in engines, gearboxes and hydraulic equipment, oil seals must prevent the leakage of oil, water and gases while simultaneously circulating fluids on the sealing surface to enable lubrication. This low level of friction saves energy. Although they may appear to be simple rubber rings, NOK is constantly upgrading these oil seals through improvements in surface functionality, material selection and structural enhancement when in contact with rotating shafts.

Using Trial and Error to Find the Perfect Blend: Oil Seals and Material Design Technology

Oil seals are one of NOK's core products. Of NOK's consolidated sales of 682.5 billion yen for the fiscal year ending March 2022, the sealing business — including oil seals — accounted for approximately 336.2 billion yen, or nearly 50%. NOK produces 60,000 types of oil seals globally, manufacturing 1.83 billion units annually. Despite their seemingly simple ring-like design, oil seals combine rubber material, metal rings, and springs to prevent oil and water leakage, achieve low friction, and ensure durability. They are essential mechanical products for all types of machinery, and one of the supporting technologies is material design.

Evolving Beyond Engine Applications: Oil Seals and Shape Design Technology

Oil seals — one of NOK's core products — vary significantly in shape, materials and structure depending on what is being sealed, the size of the shaft they are mounted on, and the type of movement involved. NOK produces around 60,000 types of oil seals, most of which are specifically designed for particular applications. While oil seals are widely used in automobiles, those used for engines and those installed in drivetrain components require entirely different properties. Despite all being referred to as "oil seals," they are fundamentally distinct products. For example, oil seals used in hub bearings near the wheels have undergone their own unique evolution.