Tel: +8615315509861

E-mail: lanyang2727@gmail.com

Home > Knowledge > Content
As the speed of the machine increases, the use of the guide rails is also converted from sliding to rolling.
- Jan 25, 2019 -

     In China, the use of sliding guide rails is still the majority due to the low speed of the machine tool

 and the manufacturing cost, but the number of machine tools using ball guides and roller guides is

 rising rapidly. Since the rolling guide has the advantages of high speed, long life, preloading, and

 convenient installation, with the improvement of machine tool performance and numerical control

 requirements, the increase of the use ratio of the rolling guide is an inevitable trend. (The moving

 speed of the machining center of the JIMT exhibition from 1996 to 2002 The number of units

 displayed on the left vertical axis and the moving speed of the horizontal axis machine tool) To

 improve the production efficiency of the machine tool, it is necessary to increase the speed of the

 machine tool.


    The velocity statistics of the machining center exhibited at the Japan International Machine Tool

 Show from 1996 to 2002, the Y-axis is the number of units, and the X-axis is the fast-forward speed.

 In Japan, the feed rate of machine tools is refreshing every year, which is obviously a trend of high

 speed. For example, machine tools with a speed of 60 m/min are increasing every year, and these

 machines use NSK products extensively. In China, machining centers with a speed of 60 m/min have

 been started, and the demand for high-speed ball screws and linear guides has also increased

 rapidly.


    NSK has been developing bearings since 1916 and has a history of producing bearings for 90 years

 and ball screws for 45 years. In recent years, NSK has also developed high-speed silent ball screws

 and high-load roller linear guides, which will provide strong support for the development of high-

performance machine tools in China. Bearing manufacturing technology is the strength of NSK. Based

 on this rolling technology, it continuously develops and produces ball screws, linear guides, spindle

 units and all rolling parts used in almost every part of the machine. In the 1980s, NSK's precision

 bearings and precision ball screws played a very important role in the process of CNC machine

 tooling in Japan.


    At CCMT2006, NSK will showcase some advanced products.


    A few years ago, Japan began to produce machine tools with speeds exceeding 100 m/min. In

 order to meet its high-speed demand, NSK has developed a BSS series high-speed ball screw with a

 DN value of 220,000 (DN = shaft diameter x number of revolutions), a quiet, new lubrication structure

 and a new circulation method.


    The high speed of the machine tool and the high acceleration and deceleration requirements make

 the load of the ball screw increase. In order to meet the requirements of high speed, a large lead ball

 screw can generally be used. However, the use of a large lead ball screw can cause insufficient load

 capacity and insufficient rigidity. The new BSS series high-speed ball screw developed by NSK

 features low noise and low vibration. Thanks to the new cycle method, the DN value, which is the

 product of the shaft diameter and the number of revolutions, can reach 220,000, which is double the

 existing product. Moreover, the noise can be reduced by 5 to 7 decibels. In addition, because there is

 no steel ball circulation pipe, the outer diameter of the nut can be reduced by 15% to 30% compared

 with the existing similar products. A high dust seal and a maintenance-free automatic lubrication

 element K1 can be added as needed. It has many specifications for medium lead and large lead, and

 its products have been well received by many large machine tool manufacturers in Japan.


    RA series


    For more than 20 years, NSK has focused on the development of linear ball guides.


    In terms of rigidity, the FEN analysis technology is used to optimize the design to minimize the

 internal deformation. For the slider, the deformation of the opening is small, thus ensuring the

 optimum rigidity.


    In recent years, China's auto industry has developed rapidly. By 2010, the annual domestic 

 production of automobiles in China is expected to reach 10 million units. The development of the

 automotive industry has also driven the development of other industries, and the demand for

 injection molding machines has also increased substantially. The demand for injection molding

 machines is not only in the automotive industry, but also in the IT and semiconductor industries in

 China as a pillar industry. There is also a high demand for high precision, high performance and high

 efficiency. The special screw for injection molding machine - HTF series is developed according to this

 demand.


    At present, the injection molding machines produced in China are basically hydraulic. In recent

 years, electric injection molding machines have been rapidly developed in Japan. The main difference

 between the electric injection molding machine and the hydraulic injection molding machine is the

 driving method. The electric injection molding machine is not driven by hydraulic pressure but   driven  by a servo motor or a ball screw. So far, in Japan, electric injection molding machines have

 accounted for 75% of the total number of injection molding machines. According to the survey data

 of the company, the ratio of electric type to hydraulic type is increasing year by year, and the electric

 injection molding machine has achieved 1000t maximum.


    The hydraulic injection molding machine is converted into an electric injection molding machine.

 The main part that needs to be modified is the injection molding part and the mold clamping part.

 Others include the injection nozzle positioning part and the mold release part. Among them, the

 injection molding and clamping part require high load bearing capacity, especially the ball screw of

 the injection part, and the plastic material with higher viscosity needs to be shot at a high speed and

 maintained, with a stroke of 20-150 mm, 100-250 mm/ The slower speed of sec, repeated movement

 under high load conditions. Therefore, for the ball screw of the injection molding part, the ability to

 move under a small stroke and have a good ability to withstand high loads is a design must pay

 attention to the ball screw.


    Due to the electrification of the injection molding machine, the bearing capacity of the ball screw is

 required. For the high load requirements of the full electric injection molding machine, NSK has

 developed the world-leading screw for the injection molding machine - HTF series ball screw At

 present, the market share of electric injection molding machines in Japan is 80%. The shape of the

 HTF series large load ball screw.


    The machine tool industry, like other industries, must pay attention to environmental issues.

 Therefore, there are certain restrictions on the use of lubricating oil and waste oil treatment. To this

 end, NSK has developed a long-term maintenance-free automatic lubrication element K1 that can be

 used on bearings, ball screws and linear guides, and promises to operate for 5 years or 10,000 km

 without maintenance.


    NSK has four technical research centers (Japan, USA, Europe, China) around the world. The

 Technology Research Center is responsible for the evaluation tests, life tests and product quality

 verification required for product development research. Technical strength. The research center of

 the technology research center has played a great role in the research of product development and

 the management of product quality, making NSK products fully trusted by customers.


    NSK prides itself on its market share in the world's number one ball screw. The market share of

 bearings is the highest in Japan and the third in the world. The market share of linear guides is the

 third in the world. The ball screw is at the highest level in the industry in terms of speed, precision

 and other major technical parameters, and is at the forefront of the world's machine tools and

 industry.