Saturday, April 22, 2017


  Nhắc đến NOK thì có rất ít ai không biết nhất là dân cơ khí. Đặc biệt là trong các sản phẩm của KOMATSU. Thông thường thì NOK chiếm từ 70 đến 85% của các loại gioăng phớt sử dụng trên các thiết bị của KOMATSU. Giải thích tại sao mà KOMATSU lại chuộng sử dụng gioăng phớt NOK đến vậy. Thực ra chỉ đơn giản là chất lượng rất tin cậy khi sử dụng và giá cả hợp lý.
  Các loại gioăng phớt NOK thông dụng:

1. Phớt dầu:
Phớt chặn dầu được sử dụng cho động cơ ô tô và mô tơ truyền động. Nó được thiết kế để  ngăn dầu khỏi chảy ra ngoài ở đuôi các trục truyền động và ngăn bẩn từ ngoài không khí vào bên trong.
Phớt dầu phục vụ để ngăn chặn sự rò rỉ không chỉ của chất bôi trơn, mà còn cả nước, hóa chất, và khí từ "khoảng trống" trong máy móc. Phớt dầu cũng giúp ngăn chặn sự xâm nhập của bụi, đất và cát từ không khí bên ngoài.
Phớt dầu là không thể thiếu và được sử dụng trong các lĩnh vực khác nhau, bao gồm ô tô, máy bay, tàu thuyền, xe đường sắt, máy móc xây dựng, máy móc nông nghiệp, nhà máy hóa dầu, và đồ gia dụng điện.
Lịch sử phớt dầu của Nhật Bản là lịch sử của NOK. NOK luôn sản xuất ra những sản phẩm chất lượng ổn định và chất lượng cao dựa trên nguyên tắc độc đáo.
2. Phớt Pa

Packings are used as sealing devices for hydraulic and pneumatic cylinders used in various machines. NOK provides a wide range of packings for many purposes, including those for pistons, piston rods, etc.
"Packing" is a collective term for sealing devices that are mounted on the moving parts of hydraulic, pneumatic, and water-pressure equipment. Packings are used for industrial equipment such as hydraulic cylinders, power shovels, bulldozers, industrial robots, and hydraulic elevators.
NOK continues to develop ideal packings that improve the reliability of industrial equipment. Examples include NOK Noxlan packings (Noxlan is a brand name for NOK polyurethane rubber, used exclusively for packings), the performance of which far exceeds the maximum limits of conventional packings.
3. O-rings

O-rings are O-shaped ring packings, and are used to seal fluids and dust. NOK has a broad lineup of rubber materials that can meet various service conditions.
O-rings are ring packings with an O-shaped cross-section. O-rings are placed in groove portions and pressed in moderately before being used to prevent leakage of fluids, such as oil, water, air, gas, and others. 
NOK uses synthetic rubbers for many purposes, including the manufacturing of O-rings that can withstand prolonged use in harsh environments.

4. Mechanical Seal

These are end-face seals that use a pair of faces perpendicular to the rotating shaft (sliding surfaces) to seal. The sealing faces, smoothly finished with high accuracy, enable long-term maintenance-free usage.

The mechanical seals manufactured by Eagle Industry Co., Ltd. feature flat and high-precision sealing faces, enabling long-term maintenance-free usage, and offer excellent performance and low running costs. 

The mechanical seals can withstand use in different applications in various pumps for automobiles, homes, civil engineering and construction, in chemical fields such as petrochemicals, nuclear energy, and space development, and have a wide range of applications.

5. Lip Seal

Lip seals, developed as axis seals for car air-conditioners, are used to seal cooling media and refrigerator oils.

Lip seals were developed as axis seals for car air-conditioners, featuring both an originally designed compact structure and materials suitable for sealing cooling media and refrigerator oils. 

These seals are manufactured in a fully automated mass-production system, and are mounted in almost all domestic automobiles.

6. Segment Seal

Segment seals are gas seals for the main shafts of aircraft engines, and are also used in rockets due to their outstanding reliability.

Segment seals were developed mainly for the main shafts of aircraft engines using technology introduced from Koppers Inc. in the US. Segment seals feature high sealing performance and durability as gas seals, as they have unique structures backed by high-precision machining technology. 

Segment seals are highly regarded for their minimal consumption of buffer gas in production lines where toxic and inflammable gases are used. They are widely used not only in rockets and aircraft, such as the domestically developed H-1 rocket, but also in general industrial fields such as the steel industry.

7. Metal Gasket 

"Soft Metal" is a brand name for a type of NOK sealing material.

Soft Metal is a new sealing raw material consisting of thin iron, stainless steel, or aluminum plates, coated on both sides with synthetic rubber. 

Since Soft Metal combines the rigidity of metal with the resilience of rubber, it is also used for sealing materials that require sound and vibration insulation properties.

8. Static Metal Packings

These are static metal packings possessing superior resilience not possible with conventional metal packings. Static metal packings have a wider range of service conditions, and require only a minimal application of tightening force.

Static metal packings are flexible static metal seals possessing superior resistance to pressure and heat (cold), that cannot be achieved by conventional gaskets, metals, or rubber O-rings. 

Their superior shape-fitting ability enables stable sealing performance, while design freedom can be expanded as they can be fitted to noncircular products (ellipsoids, triangles, and ovals). 

NOK also provides ECOCS, the low-cost alternative to static metal packings.

9. Seal Washers

Seal washers prevent dust intrusion and oil leakage from the threaded portion of bolts. 

NOK seal washers prevent not only intrusion by dust or dirt, but also the leakage of oils or other fluids from the threaded portions or flanges of bolts or nipples of various machines, such as hydraulic or water-pressure machines for automobiles, construction machines, and transporting machines. 

The seal washers use a specially blended synthetic rubber developed by applying the rubber technique for oil seals. Thus they have superior tear strength, mechanical strength, and resistance to heat, cold, and oils. They also provide stable sealing performance even when they are used for special applications.

10. Magnetic Fluid Seals

Magnetic fluid seals are sealing devices in which magnetic fluids are used as the sealing material. Magnetic fluids have the characteristic of being drawn to a magnet. 

As opposed to conventional oil seals or mechanical seals, magnetic fluid seals are clean seals that utilize magnetism to hold a magnetic fluid around a rotating shaft to form a fluid O-ring. 

Magnetic fluid seals are used as dust seals for hard disk drives, in which a clean environment is required, and as vacuum seals for semiconductor manufacturing equipment and liquid display manufacturing equipment.