Ball Screw Assembly: SERVICE & REPAIR

A ball screw is a linear actuator with a screw shaft and a nut containing ball bearings. Ball screws convert rotational motion to linear motion, transferring forces to a stationary or dynamic load with repeatability, precision, and accuracy. The balls roll between the helical grooves of the screw shaft to reduce sliding friction.

DB Rubin Engineering & Sales offers unmatched ball screw assembly repairs and services, including ball screw rebuilding, regrinding, emergency repairs, and reverse engineering for much less than OEMs charge.

What Are the Components of Ball Screws?

The following primary components comprise a typical ball screw assembly:

  • Screw Shaft: The screw shaft is a long cylindrical shaft with grooves in a helical shape. A motor generates energy that rotates the shaft.
  • Nut: The nut houses the ball bearings around the shaft, allowing them to travel along the helical grooves. It also has a ball recirculating system enabling the balls to return to the starting point.
  • Ball Bearings: Ball bearings are precision fit to the helical grooves of the shaft and nut, touching one or two contact points of each component and reducing friction as the ball screw assembly moves.

Types of Ball Screws

There are several types of ball screws classified by their recirculation mechanism, including:

  • Internal Ball Recirculation: The ball bearings remain inside the nut housing throughout the recirculation process.
    • Deflector-Type Ball Screws: This return mechanism relies on a deflector to lift the balls over the screw shaft diameter and back into the groove.
    • End Cap-Type Ball Screws: A mounted end cap guides the ball through an internal tunnel and back to the starting point.
  • External Ball Recirculation: The balls recirculate after traversing the outside of the nut housing.
    • Ground Screw Threads: Ground screw threads are formed from an abrasive cutter. The resulting groove surface is smoother than the rolled screw.
    • Return Pipe-Type Ball Screws: An external tube on the side of the nut carries the balls back to the starting point.
    • Rolled Screw: A cold working deformation process produces rolled screw threads. The plastic deformation creates a high-strength screw shaft.

Applications of Ball Screws in Machinery

A ball screw offers several benefits to machinery that generates linear motion from rotational energy. The reduced friction of the ball screw makes the machine’s life cycle longer and more predictable, as the equipment runs more efficiently on less motor power. Ball screws also enable machines to handle heavier loads with higher precision and improved force, speed, and duty cycle.

How to Choose the Best Ball Screw for Your Application

The ideal ball screw will improve the lifecycle and dependability of your machinery. Determine the best ball screw for your application using the following criteria:

  • Axial Load: Axial load depends on the orientation of the application. Axial load in vertical applications is the actual weight of the load. In horizontal orientations, axial load is the actual weight of the load multiplied by the load support bearings’ coefficient of friction.
  • Design Life Objective: The design life objective is the distance in inches the nut will travel during its lifecycle. A ball screw requires an adequate dynamic load rating to accommodate the inches it will travel.
  • Critical Speed: Critical speed is the intended operating speed within the ball screw’s safe limits. Determine the critical speed using screw length, screw diameter, and end mounting rigidity.
  • Safe Compression Load: The compression load prevents the screw from buckling under a heavy load. Determine the safe compression load using the distance between the load and the ends of the bearings, the rigidity of the mounting ends, and the load itself.

Ball Screw Repair & Rebuild Services

DB Rubin Engineering & Sales offers several ball screw rebuild and repair services to ensure your ball screws perform and have an optimal lifecycle. Our core services include:

  • Emergency repair services
  • Nut or screw regrinding
  • Reverse engineering
  • Recondition or repair of any design

Ball Screw Repair Services by DB Rubin Engineering & Sales

DB Rubin Engineering & Sales provides the following ball screw repair services:

  • Emergency Reload Services: This service helps eliminate backlash and other issues associated with space between the ball, nut, and screw shaft.
  • Regrind Capabilities of Screw or Nut: Regrinding the nut or screw allows for smoother movement of ball bearings by eliminating pitting in the groove.
  • Manufacture of Completely New Ball Screw Assembly: We can create a custom ball screw assembly to replace an existing one or for a new machine.
  • Reverse Engineering of Old Units: We can replace an older ball screw at a fraction of the cost of the OEMs.
  • Internal Ball Return Nuts: We repair and service internal ball recirculation systems.
  • Precision Ground Ball Screw Assemblies: Our precision grinding capabilities allow ball screw components to fit together and operate properly.
  • External Tube Nut Design: We can custom-design an external return system for your application.
  • Rolled Thread Ball Screw Assemblies: We repair and service rolled thread ball screw assemblies.
  • Flop Over Nut Design: We can custom design a flop over nut to suit any application.
  • Acme Screw Assemblies: We repair and service acme screw assemblies.

Types of Ball Screw Brands Available

DB Rubin Engineering & Sales repairs, services, rebuilds, and reverse engineers ball screw assemblies and components from the following brands:

  • 20th Century
  • Beaver
  • Cincinnati Milacron
  • Giddings & Lewis
  • Modern American
  • NSK
  • Rotex
  • Saginaw
  • Sargent
  • Skully Jones
  • THK
  • Tsubaki
  • Warner

Ball Screw Rebuild and Repair Services From DB Rubin Engineering & Sales

A ball screw assembly includes three primary parts that must be precision designed and engineered for optimal performance. Ball screws extend the life and performance of machinery by reducing the friction caused by creating linear motion from rotational energy.

DB Rubin Engineering & Sales can design and engineer ball screw assemblies and parts, reverse engineer components at a considerably lower cost than OEMs, and repair and service nearly any ball screw from the top brands. We specialize in servicing out-of-production and obsolete machine tools, including spindles, chip conveyors, electric controls, drives, and ball screws. Our remanufactured and refurbished products will meet or exceed current OEM standards.

Request a quote on the ball screw service of your choice today.