Barnes Industries, Inc.

HISTORY OF BARNES INDUSTRIES
Barnes Industries was founded in 1969. It is the first and only ball screw manufacturing plant devoted to reconditioning ball-bearing leadscrews, and producing new ball screws with a warranty for all services. "Barnes" has grown from a one-man, 1000 sq. ft. shop to more than fifty people and an excess of 60,000 sq. ft. of floor space. The facility consists of 48,000 sq. ft. of environmentally controlled space devoted solely to manufacturing. The balance of floor space is used for engineering, sales, administration and accounting.

Barnes Industries, Inc. Founded 1969. The first and only manufacturing plant devoted to reconditioning ball-bearing leadscrews and producing new ball screws.	Glenn R. Barnes, Founder Active Owner and President

WHY BALL SCREWS FAIL
Ball screws fail in machine tools due to one or more of these conditions: 1. normal wear; 2. poor maintenance (lack or excess of lubrication); 3. accidents resulting from electronic malfunctions; 4. poor design-under capacity; 5. too high preload; 6. bent leadscrew; 7. misalignment (improper installation); 8. environmental; and 9. operator error.

Ball leadscrews are machined from top quality material, hardened and ground to super-precision tolerances. They usually do not need replacing when worn. As a result, it is economically feasible to service all types of ball screws by regrinding the screw and installing new nuts, balls and seals.

CUT MACHINE DOWN TIME
Metalworking plants can cut machine tool down time by reconditioning worn or damaged ball bearing leadscrews. Barnes Industries can service any worn screws and provide a warranty which depends upon the type of processing: 1. Reloaded, 2. Reconditioned and 3. Replaced with new screw.

WHAT "BARNES" CAN DO FOR YOU
Barnes Industries can effectively recondition ball screws with any of the designs of nut packages made by leading manufacturers with either external or internal ball return systems. Refer to "How a Ball Screw Works" for more information.

New nuts for reconditioned ball screws can be made with the original mounting configurations, but with an increased load-carrying capacity in many cases. This results in an increase in the life of a ball screw. When the original ball nut can be used in the repair of the ball screw, the ball raceways of the nut are never reground. Regrinding can destroy case depth and hardness, severely affecting the life of the ball screw assembly.

CAPACITY
Barnes Industries is completely tooled and has thread grinding, straightening, turning, milling, lead checking and inspection equipment to recondition or manufacture new ball screws up to a maximum of 6-in. diameter by any length. For ball screws larger than 6 in. diameter consult our sales department.

PRICE
To determine the cost of reconditioning a ball screw it should be shipped prepaid to Barnes Industries for a no-charge inspection. Proper inspection requires complete disassembly of the unit. After disassembly the ball screw and ball nut raceways are checked for wear and metal fatigue. The screw journals, keyways, V-threads, and snap ring grooves are also inspected. The ball screw, if in good condition, is also inspected for straightness and lead accuracy. When the type of servicing and cost is determined, the customer is notified for a purchase order approval before any other operations are carried out. Our sales department will give firm not-to-exceed costs for our various types of service and the delivery times at the time of inquiry.

DELIVERY
Barnes Industries provides fast delivery on all reconditioned ball screws to reduce customer down time to a minimum. This is made possible by our extensive stock of popular models of new and reconditioned units for exchange and our inventory of new ball nuts and components. In cases where the ball screw is not repairable, a new replacement can be made.

WARRANTY

Table 1 - Ball Screw Assembly Specifications and Warranties

*Barnes Option: If Barnes determines a screw non-reloadable and customer wants it reloaded, no warranty applies.
** On housing mounted units, new or original housing is used.
***Customer will be notified of lead accuracy.
+Ball screw raceway hardness must be Rc-58 minimum for full 18 month warranty to apply.
++ Ball screw will be warranted for 24 months or 20 million inches of travel whichever comes first.

SPECIAL SERVICES FOR CUSTOMERS
Customers who wish to have insurance against machine down time should contact our sales department for a special inventory program.

For ball screw users who are currently having ball screw problems, we will assist in re-engineering and building a unit to fit the particular application.

EMERGENCY REPAIRS
We have on hand a large supply of original salvaged usable parts from major U.S. and foreign ball screw manufacturers. These parts are on hand for emergency repairs only and are never used in our reconditioning process. These repairs carry no warranty.

REPAIR OF BEARING JOURNALS
Bearing journals that are undersized, scored, damaged or bent are repaired by a process determined by inspection, Figs. 2 and 3. Repaired journals meet AFBMA specifications for Class ABEC-5 or better.

Bearing journals that have been broken off can be repaired by a special process. Ship ball screw and journal pieces to us. We will engineer and install a new journal that meets AFBMA specifications, Figs. 2A and 3A.

RELOAD AND MINOR REPAIR
In rare cases a wear condition can be corrected properly by reloading the nut and screw with over-sized balls. The reloading procedure is carried out only if the following conditions are met:

• The ball screw and nut thread raceways are in good condition.
• The ball screw and nut raceway radii and root diameters are in tolerance for the ball that is to be used in reloading. This insures that the ball comformity and contact angle are correct.
• The ball screw thread root diameter must be straight or require minimal lapping.
• The ball screw thread lead must be within machine tool tolerance. Customer approval is required if lead is out of tolerance.

Only if these four critical conditions are met will the ball bearing leadscrew be reloaded and given a 6-month warranty. Should an emergency condition exist, and Barnes Industries does not have an exchange unit in stock, they will make the unit functional, if possible, with no warranty. At the same time, a drawing can be made and quoted for the manufacture of a new unit on an emergency basis.

Sometimes on integral preloaded nuts (even in good condition), an over-sized ball used to offset wear and to establish preload will not run at the proper contact angle. This results in short wear life and the reload procedure is not carried out, even if items 1 through 4 are good. Under this condition, reconditioning requires a new ball nut. This process is given a 12-month warranty.