Extenda Life Crossarm
What are Extenda-Life Crossarms?
Download Extenda-Life PDF FileExtenda-Life Crossarms (Patented) are the culmination of several years of research and
testing at Brooks Manufacturing Co. in an effort to extend the useable life of our products.
Extenda-Life Crossarms are the same superior quality crossarms that Brooks has produced for
decades, with the addition of a specially designed nail end plate hydraulically pressed into each
end. These plates are not the same as "truss plates" with which most people in the industry are familiar. End plates are designed specifically for end grain application and have a special tooth design and pattern that
locks itself in forming a permanent bond that prevents them from pulling out.
Project History
Brooks Manufacturing Co. was asked by a major utility to find a way to eliminate premature failures of
crossarms due to the ends splitting. In conjunction with this utility, Brooks conducted a study of
crossarms that had been taken out of service. Based on the data developed through this research project,
it was determined that 15% or more of these crossarms would not have needed replacement if end
splitting had been prevented.
Brooks developed a nail end plate that can be pressed into the end of the crossarms, and conducted several
tests to determine if the use of the nail end plate would eliminate end splitting in crossarms. The purpose
of nail end plates is to help maintain the structural integrity of the crossarm over very long periods of
time, by holding the wood together, and not allowing checks to turn into splits. By preventing splitting, the
nail end plate not only prevents insulator pins from pulling out of the ends, but also prevents rotting that
can occur when a split penetrates past the preservative layer.
Why Use Extenda-Life Crossarms?
The resulting cost savings to utilities goes far beyond the cost of the crossarm. Our research showed thatthe total cost to replace a crossarm varied between $1,000 and $8,000 depending on the equipment and
personnel needed, the location of the structure, and the costs related to outages. This data showed that
the cost savings involved with extending the life of crossarms is substantial.
Extenda-Life Crossarms will last longer and perform better than standard crossarms. Some of the benefits
include:
- Eliminates end splitting of the crossarms.
- Prevents insulator pin pullouts due to splits.
- Nail End-Plated Crossarms will improve distribution line reliability.
· Reduce catastrophic failures in the field under severe loading conditions.
· Provide substantial long-term cost savings by extending the life of the crossarm and reducing
expenditures for labor, equipment, and materials.
· Eliminates the need for other anti-split devices such as anti-split bolts.
· Allows for date tracking of crossarms.
