Ball Screws for Special Applications

Overview of Ball Screws for Special Applications

Outside of the standard requirements, A.MANNESMANN ball screws can be designed for a wide range of special applications. As a manufacturer with extensive production capabilities, we are able to completely custom develop and produce ball screws from the requirement profile of the application area.

Extraordinary installation environments and application conditions also require extraordinary ball screws so that a sufficiently high level of functional reliability can be achieved in all operation phases. If it is usually chips, dirt and cooling lubricants that can greatly impair a ball screw, then additional influencing variables are added here.

Ball Screws for Special Applications are Frequently Used in the Following Areas:

• Semiconductor industry
• Vacuum technology
• Medical technology
• Food industry
• Power plant technology
• Shipbuilding
• Aircraft construction and aerospace
  
  

Examples of Ball Screws for Special Applications:

• Corrosion-resistant ball screws
• Hybrid ball screws
• Ball screws for minimum quantity lubrication
• Cooled ball screws
• Ball screws with monitoring sensors
• Coupled ball screws
• Telescopic ball screws
• Two-start ball screws

Corrosion-Resistant Ball Screws

If the usual corrosion resistance of nitrided ball screws is insufficient, then the spindles and the nuts can also be made, for example, from Cronidur or with a corrosion-inhibiting coating. In order to achieve corrosion protection with the balls as well, these either consist of hard metal or ceramic.

Hybrid Ball Screws

Ceramic balls are also used with hybrid ball screws. They are assembled in combination with steel nuts and spindles. The special advantage of hybrid ball screws lies both in the ease of movement as well as in the insensitivity in the event of a lack of lubricant.

The ball screws work almost exclusively here in the range of static friction and boundary lubrication. Since the breakaway torque acts in this work area, these ball screws must be designed to be extremely low-friction. Special ball recirculation systems, special ball arrangements and precisely coordinated running strategies allow for a high level of operational reliability, even with short-stroke or oscillation applications.

Ball Screws with Minimum Quantity Lubrication

The functional reliability and durability of a ball screw depends greatly on the lubrication. In principle, there is no hermetic seal between the nut and spindle due to the geometric relationships of the screw of a ball screw. There is always a minor lubricant discharge, which must be compensated for. A higher operational reliability can often be achieved with a continuous supply of lubricant, such as an oil-air minimum quantity lubrication. The outflowing air flow protects the nuts from externally penetrating impurities. The demand-oriented dosing simultaneously reduces the continuously supplied amount of lubricant. Since the action area in the nut is limited with an oil-air lubrication and the specifically and sufficiently metered atomized mixture can reach the contact points of the balls, special measures are required to ensure the optimal supply of lubricant to the interior of the nut.

Cooled Ball Screws

Heat is generated (about 100 to 200 W frictional heat), even if the friction is very low with ball screws and the power loss is minimal. This heat is disruptive and so should be kept as low as possible. Cooling measures in the spindle and on the nut can significantly lower the operating temperature.

Ball Screws with Monitoring Sensors

The operating temperature is a characteristic value that is easy to measure, which provides good reliable information about the operating condition of the ball screw. A temperature sensor on the nut reports the current operating temperature, which is compared with corresponding limit values. The temperature monitoring can be used to derive service measures if necessary, which extend the durability.

Another way to get information from the inside of the ball screw is to measure the vibrations and oscillations by using an accelerometer on the nut. A targeted frequency analysis here can detect possible damage at an early stage and initiate appropriate measures. However, interpreting the frequency analysis requires special expertise, which we are happy to provide.

Since most ball screws are equipped with a non-rotating nut, these can be prepared for the installation of corresponding monitoring sensors.

Coupled Ball Screws

If ball screw spindles are required in very long lengths, the prompt provision of the corresponding starting material may be problematic. To be able to produce such spindles nevertheless, inseparable coupling connections were developed, which make it possible to create shorter spindle parts without sacrificing quality.

Telescopic Ball Screws

If a very compact and short ball screw is required, then a telescopic ball screw is the right solution. Two ball screws are interconnected so that both axial displacement movements occur at the same time. A ball screw works according to the driven nut system here and the other ball screw works according to the driven spindle system. Telescopic ball screws offer extremely interesting and innovative drive solutions.

Special ball screws with double nuts and large thread pitches require a considerable axial installation space. Two-start ball screws are a very sensible design version in order to reduce this.

Application Areas

In order to implement certain applications, special designs of ball screws are often required whose technical structural implementation is largely determined by the application. This often results in new application opportunities in various industries.