AM Machine Components
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A.MANNESMANN A member of SCHNEEBERGER linear technology

A.MANNESMANN A member of Precision SCHNEEBERGER linear technology Manufacturing partners of internationally successful Companies producing machinery of high demand. AM Ball Screws Precision components for trans mission of motion and power at maximum efficiency. Quality advantages ® Free and easy motion with the greatest axial rigidity, i.e. also minimum loss of friction under load. • Smooth running nuts without jerk, minimum torque variation - also for the advantage of long-time application without wear. • Rolling resistance of the ball tracks as well as wear and shock resistance are the...

AM Quality -An additional value for performance and life rating Deep-nitrided AM ball screws have been giving excellent service for decades. Precision As one of the first manufacturers, we have continued development through advancing technology by a continual interchange of experience with leading users of these machine components. This publication introduces you to the outstanding quality of the AM system. It contains useful technical data and information on design and calculations for the engineering department. Our individual consultancy service is ready to provide advice to make your...

Lengths continuous thread lengths up to 10,000 mm and above this length as a coupled design Nominal diameter/lead combinations as specified in German standards DIN 69051, part 2 other leads upon request AM system with deep-nitrided screws Ground ball tracks of screws and nuts Special designs From experience gained over many years we can confidently recommend our deep-nitrided screws. The greater hardness of the thread flanks ^ 900 HV = 67 Rockwell and high core strength of the material (850 -1,000 N/mm2) have the following benefits: • increased wear resistance • increased fatigue strength •...

AM Ball Screws perfect in • high speed application • positioning accuracy of highest resolution • highest dynamic, also in • long-time application

Wiper seals Our system of ball recirculation proved over many years has been continuously developed to the utmost perfection. In certain cases of application characteristic values up to nperm x d0 = 200,000 are achievable, speed rates up to 150 m/min and accelerations up to 20 m/sec2. Please inform us about your special case of application. Optimised geometry and manufacturing precision ensure ease and smoothness of ball transfer within the walls of the nut. This produces uniform and quiet running at all speeds and high axial rigidity with the least friction. The threads in the nut are...

Special designs Telescopic Ball Screws draw ratio i max. height hmax largest 0 dynamic load rate Cdyn max. number of rotation nmax hollow-bored ball screws e.g. 370 x 20 mm

Life rating L This is a nominal period of operation, computed for a given load and speed of rotation, at the end of which 90% of seemingly identical ball screws are not expected to exhibit any signs of fatigue (pitting). For example in case of 50% security (instead of 90%) the calculation results in a quintuple life-rating. The real life time is significantly affected by design, material and production of the ball screw. This is the reason for our long-time success. The manufacturer or the user of the machine has to take care for keeping the ball screw protected against probable...

Influence of the nut preload on the life rating The relevant operation force Fai gets a further force by the preload Fpr. The operation force becoming effective by this result can be taken from the diagram beside. You have to take Fwi (instead of Fai) for the load spectrum of the life rating calculation. After the multiple of 106 load revolutions the fatigue L106 begins statistically. The number of revolutions nm determines the duration of fatigue = screw’s running time Lh1 in hours. The hours of the machine utilization time Lhm determine the utilization time of the machine by the operating...

Permissible speed of rotation nperm. The calculated values are to be understood as an approximation. For an exact calculation we ask you to contact us. *) directionally stable mounting Transverse resonant vibration is excited in any shaft which exceeds its permissible speed of rotation. On ball screws this results in excessive radial loading of the nut system. The maximum permissible speed of rotation is 20% below the critical speed .This safety factor has been taken into account in the diagram below. The concrete execution of screw bearing is of great importance for the permissible speed...

Permissible compressive axial load Fp0mv The permissible axial load can be determined from the following diagram as a function of the screw bearing, the nominal diameter d0 x lead P and the screw length L„. Concerning the compressive axial load Fk the diagram includes a threefold safety factor (v = 3). The static load rate C0am is the load limit which causes a plastic deformation of 10'4 x ball-0 under standstill condition. C0am see data sheet *) directionally stable mounting Steps for increasing the permissible compressive axial load • Adoption of bearing arrangement D • Application of a...

Ra* Rnu Rs • k k =1 in case of fixed bearing one side =4 in case of fixed bearing both sides Rnu =nut rigidity on nut flange Rs = Spindle rod rigidity per m (see following table) Ls = loaded length of spindle in m Approx, values for rigidity of nuts and spindle rod rigidity per m *) Values for preloaded double nuts with P =10 mm, other leads see data sheet. AM offers you the ideal combination of -high axial rigidity with - low no-load torque The result: high grade of efficiency and low operating temperature (see picture page 13) Preload Fpr Ball screws for high-dynamic machine axis with...

The natural rolling power in the contact area of the rolling bodies is an unavoidable loss. Therefore, the real value of efficiency r|a is always some percent under 100%. =tan tp transformation of a torque 11a tan (cp+p) into an axial force =tan (cp-p) transformation of an axial a_ tan cp force into a back torque The angle of friction p is determined by manufacturer’s specific features: • form of ball tracks of screw and nut • manufacturing accuracy • surface hardness of screw and nut • surface quality of the ball tracks • recirculating system Users’ operation data: • axial load and...