PRECISE MOTION

We have been manufacturing ball screws since 1967 and we deliver them almost all over the world. To provide our customers with the highest quality of the products and co-operation, we keep investing a lot of effort in continuous improvement. Thanks to this effort, every year we fight for the top positions in the leading innovative competitions. A certificate of quality in compliance with EN ISO 9001:2008 proves that our quality management system is at a high level. We also aim for maximum support of the industrial machinery development activities in our area, for which we participate in the following...

2 • GENERAL INFORMATION ON BALL SCREWS, FAQS Ball screws (hereinafter BS) are structural elements, which transmit the rotary movement to straight movement with high efficiency (these screws are not self-locking). They feature high rigidity, accuracy and durability. The ball screws are used in various machinery sectors, especially due to their high efficiency ensured by a low rolling resistance. BSs are most often used in the following sectors:

GENERAL INFORMATION ON BALL SCREWS, FAQS 2.2 tandard manufacturing technology for making the ball screw thread S Accuracy and quality of the ball screws are largely dependent on the manufacturing technology selected. Generally, the following technologies are mainly used to produce the ball screw thread: Ground thread • Grinding (achieved accuracy class of the ball screw shaft thread pitch up to P1). • Rolling (achieved accuracy class of the ball screw shaft thread pitch up to T5). Rolled thread 2.3 Ball screw profile To achieve the maximum transmission efficiency, it is necessary to make an ideal...

GENERAL INFORMATION ON BALL SCREWS, FAQS 2.4 Ball screw preloading methods Preloading method Used on the ball nut units Preloading method diagram Preload using a spacer ring Preload using differential nut thread pitch Preload using the difference between individual threads (for multiple-start ball screws) 2.5 aterials used for manufacturing of the ball screws and their M heat treatment To manufacture the ball screw shafts, we use steel with the grade of 42CrMo4. To manufacture the ball nuts, the most often used steel grade is 100CrMn6. Nuts and the threaded part of the shaft are hardened to 58–60...

GENERAL INFORMATION ON BALL SCREWS, FAQS 2.6 Load capacity (ratings), rigidity and recirculation system lifetime a) Static load capacity (Co) is a static load, which corresponds to the permanent deformation of the ball and the running surface in the most stressed touch point; equal to 0.0001 of the ball diameter Dw. b) Dynamic load capacity (Ca) is a permanent, invariable load, which may be (in theory) transmitted by the ball screw with the basic lifetime parameter L10 = 1×106 revolutions. The following equation is used to determine the basic lifetime, which is defined as number of shaft revolutions...

BALL SCREW SELECTION GUIDE BALL SCREW SELECTION GUIDE A complete configurator of ball screws is freely available on our website. Partial steps of this configurator are shown below. The selection of the ball screw version from the offered production range is driven mainly by the functional specification, required features and operating conditions. If you need any assistance with the design proposal, please contact our technical support, who will help you with the design proposal. BALL SCREW TYPE SELECTION SELECTION OF THE BALL NUT UNIT TYPE DETERMINATION OF THE BALL SCREW RECIRCULATION SYSTEM...

BALL SCREW SELECTION GUIDE 3.2 election of the ball nut unit type S Description Non-preloaded nut without flange Double preloaded nut without flange Double preloaded nut with flange Preloaded nut with flange End cap return high-speed (fast-running) preloaded nut with flange Non-preloaded nut with flange for shafts with rolled thread Non-preloaded nut with flange Driven nut with inserted bearings 3.3 etermination of the ball screw recirculation system D Nominal thread diameter d0 is selected in the tables (chapter 4) based on the dimensions available and the required application. Nominal thread...

ons of the thread diameter and pitch can be found in the tables (see the chapter 4). 3.4 Thread pitch specification Thread pitch P determines the nut travel per one rotation of the ball screw shaft. The standard offered combinati Thread accuracy class - the ball screws are offered in several accuracy classes, which are described in more detail in the ISO 3408 standard. The highest accuracy class are often used in cases where very precise positioning is required (e.g. machine tools). Lower accuracy classes are often used for applications where the positioning precision requirements are not high...

BALL SCREW SELECTION GUIDE 3.7 Preload specification Based on the positioning precision and rigidity required, the proper ball nut mating on the shaft method should be selected. The higher the preload, the shorter ball screw transmission lifetime. The following options are available as standard: • Fitted nut with axial play • Fitted nut with preload corresponding to 5% of the dynamic load ratings (suitable for precise positioning and moderately loaded screws) • Fitted nut with preload corresponding to 10% of the dynamic load ratings (suitable for precise positioning and more loaded screws) •...

4 • BALL SCREW DESIGN // Precise Screw BALL SCREW DESIGN 4.1 Precise screw This type of ball screws is mostly used for the practical pur- and wide range of variants. Usually they are screws with poses due to its versatility, excellent technical parameters ground threads. Basic technical parameters: • Diameter from 12 to 180 mm • Length up to 15.5 m • Accuracy classes P1 to P5 • Minimum strength of the shaft material is Rm = 800 MPa • Efficiency approx. 94-97 % • Operating temperature -40 °C to +80 °C (acc. to the lubricant type) Category characteristics: • Precise positioning screws • Wide choice...