Ball Screw Rod for Screw Jack System

Ball Screw Rod

The ball screw consists of a screw, a nut, a steel ball, a prepress plate, a reverser, and a dust-proof device. Its function is to convert rotary motion into linear motion, which is the further extension and development of the Ekem screw. This development's critical significance is changing the bearing from sliding to rolling motion.
Ball screw bearings provide a wide range of standardized products for various purposes. It is widely used in machine tools. The circulation modes of the ball are circulating conduit type, circulator type and end cap type. The preloading methods include positioning preloading (double nut method, position preloading method) and constant pressure preloading.
The appropriate type can be selected according to the purpose. The lead screw includes precision ball screw with high-precision grinding processing (accuracy is divided into 6 grades from CO-C7) and cold rolled ball screw bearing with high-precision cold rolling processing (accuracy is divided into 3 grades from C7-C10). In addition, in order to meet the urgent need of users for delivery, there are also finished products that have been processed at the end of the shaft, semi-finished products that can be traced at the end of the shaft and cold rolled ball screw bearings. As the peripheral parts of the bearing, the necessary lead screw support unit, nut support, lock nut, etc. have also been standardized for users to choose.
Based on the product technology accumulated over the years, the ball screw bearing is managed by strict quality assurance system from material, heat treatment, manufacturing, inspection to shipment, so it has high reliability.

Ball Screw Rod for Screw Jack System

Feature of Ball Screw Rod

1. Low friction loss and high transmission efficiency
   Since there are many balls rolling between the ball screw shaft and the ball screw nut of the ball screw pair, higher movement efficiency can be obtained. Compared with the past sliding lead screw pair, the driving torque is less than 1/3, that is, the power required to achieve the same movement result is 1/3 of the sliding lead screw pair. It is very helpful in saving electricity.
2. High precision
   The ball screw pair is generally produced continuously with the world's highest level of mechanical equipment, especially in the factory environment of grinding, assembly and inspection processes. The temperature and humidity are strictly controlled. Due to the perfect quality management system, the accuracy is fully guaranteed.
3. High speed feed and micro feed may
   Because the ball screw pair uses ball motion, the starting torque is very small, and there will be no creeping phenomenon like sliding motion, which can ensure accurate micro feed.
4. High axial stiffness
   The ball screw pair can be preloaded. As the preload can make the axial clearance reach a negative value, higher rigidity can be obtained (by applying pressure to the ball in the ball screw, the repulsion force of the ball can increase the rigidity of the nut when it is actually used in mechanical devices).
5. Non self locking, reversible transmission

Technical Parameter of Ball Screw 

How Ball Screw Works

1.  Ball screw assembly
   The ball screw assembly consists of a screw and a nut. Each screw and nut has a matching spiral groove. The ball rolls between these grooves to provide a unique contact between the nut and the screw. When the screw or nut rotates, the ball is deflected into the ball return system of the nut by the guide, and reaches the other end of the ball nut through the return system in a continuous path. The balls are then discharged from the ball return system into the ball screw and nut thread raceways for circulation in a closed loop.
2. Ball nut assembly
   The ball nut determines the load and life of the ball screw assembly. The ratio of the number of threads in the ball nut circuit to the number of threads on the ball screw determines how much faster the ball nut reaches fatigue failure (wear) than the ball screw.
3.  The ball nut is manufactured with two types of ball return systems
   (a) External ball return system. In this type of return system, the ball returns to the other end of the circuit through the ball return pipe, which protrudes above the outside diameter of the ball nut.
   Ball nut external system
   (b) Internal ball return system (there are many variants of this type of return system) The ball returns through or along the nut wall, but below the outside diameter.

Processing Technology of Ball Screw

Rolling ball screw is a kind of low cost feed screw. It uses the lead screw shaft formed by rolling and ground by special surface to replace the expensive grinding lead screw used in the lead screw. Compared with the traditional turning method, lead screw rolling has the advantages of production, metal saving, good mechanical properties of rolled pieces and simple operation; The lead screw rolling process is divided into hot rolling and cold rolling, especially the cold rolling lead screw. Due to the improvement of strength and hardness, the service life of the lead screw is greatly extended.

With the development of industry, the demand for automation equipment is gradually increasing, and the application of the rolling ball screw is gradually popularized. The ball screw is produced by the rolling process, induction hardening, and the hardness is above HRC58 degrees. Under the same diameter, the length of this series of ball screw pairs is longer, which can be 2 meters; The lead screw and nut are produced in a standardized mass production, with short delivery time and low cost.