Gradel-Baudin ball screws are manufactured by cold forming. This process consists of deforming a smooth metal bar by pressing it by rotation using tools called knurls to obtain the thread. We use carbon alloy steels, known for their high quality: C55R (1.1209) or CF53 (1.1213). After rolling, the screws undergo surface induction hardening. This type of heat treatment hardens the surface of the screw, while preserving the mechanical characteristics in the core, which guarantees good wear resistance and improves resistance to fatigue. Finally, the screws are cleaned, polished and checked one by one.
Technical benefits
The action of the balls transforms the friction of a simple screw/nut system into a bearing which reduces overheating and therefore wear. The purpose of this system is to achieve smooth, fast movements and more accurate positioning. Mechanical efficiency and service life are much higher. There is no "stick slip" effect. The drive power required is reduced and the ball screws can be reversed. The ball screw/nut system is a particularly quiet system.
Fields of application
The ball screw/nut system is generally used in precision machines (machining centres, machines with high feed and rotation speeds, drive systems, etc.), medical equipment, presses, cutting machines, etc.
Irreversibility
Due to their excellent efficiency of over 90%, ball screws are reversible systems. To hold the system in position, it is necessary to put a brake on the activated system.
Lubrication
The recommendations for the lubrication of ball screws are the same as for ball bearings; they can be lubricated either with oil or grease. When delivered, the screw/nut assemblies are supplied with a greasy rust protection film. When assembled, the ball screw/nut assemblies must be lubricated with a lubricant suitable for the intended use, the behaviour of which must be checked on initial start-up. If the effect of rotation expels it, it is necessary to choose a higher viscosity. It should be noted that a single lubrication is insufficient in most cases and it is advisable to top up after the first few trips and to determine the frequency and doses required. Finally, the same type of lubricant should always be used so that regular and appropriate lubrication protects the ball screw/nut assembly against corrosion and reduces wear.
• For grease lubrication, use grease type KPE2R-20 according to DIN 51502
• For oil lubrication, mineral oils are suitable for ordinary temperatures
• For high temperature operation, use a synthetic oil
Précisions
• Profile: Gothic profile with 5- or 10-mm pitch
• Material: C55R (1 .1209) or CF53 (1 .1213) treated
• Raceway: induction treated at 700±50 HV and polished
• Accuracy: screws delivered in T7 quality (on request possibility of T5, T9 or T10 qualities)
• Operating temperatures: from -20°C to + 80°C
