Carlisle's SA series brakes have taken the SAHR concept to a new level of performance, reliability and quality. Equipment India scoops out the details from T Natarajan, Director (Sales), CIBF.

First developed in 1997 and successfully used in the field ever since, Carlisle Industrial Brake & Friction?s SA7000 park brake has spawned a series of SA brake products and myriad competitive imitations. SA brakes are spring applied hydraulically released (SAHR) sliding caliper brakes used in static and secondary off-highway applications. In recent years, Carlisle has developed SA2500 and SA14000 models to broaden the application and industry reach of this classic park brake.

SAHR brakes, which first appeared in the late 1980s, use springs to apply a clamp load on the brake disc and to prevent unintended motion of the machine. To release the brakes, hydraulic pressure is used to compress the springs, thereby removing the clamp load from the brake discs. Upon release of the brake by the operator, the hydraulic lines to the brake pistons are pressurised. The piston then compresses the springs and forces them into a caged position. With the springs caged and the clamp load on the brake disc relieved, the machine is free to operate. When hydraulic pressure is relieved from the brake pistons by the operator or machine shut down, the springs are released from their caged position, and the brake is applied, rendering the vehicle safe from movement.

?SAHR brakes hold several advantages over mechanical park brakes. SAHR brakes simplify the brake system by eliminating linkages and cable pulls, translating into fewer parts for service and maintenance. SAHR brakes are automatic in application, meaning that the brakes automatically come on when the vehicle is shut off while a lever needs to be pulled for a mechanical brake to be triggered,? says T Natarajan, Director (Sales), Carlisle Industrial Brake & Friction.

Natarajan points out, ?Carlisle?s SA series brakes have taken the SAHR concept to a new level of performance, reliability and quality. Used in varied off-highway industries such as mining, agriculture and construction, the SA series brakes contain a return spring device for centering the caliper on a disc, keeping the brake from shifting while preventing brake drag and premature lining wear. A second unique quality of the SA series brakes is the ease of adjustment, resulting in easy lining changes and quick maintenance. Removing the end cap and turning two adjustment bolts is all that?s required. A further advantage of the SA series of brakes is its use of magnets, which pull the brake lining back from the disc. This feature eliminates lining chatter and reduces noise considerably.?

?Carlisle SA series park brake reliability is a result of over 50 years of experience in the off-highway braking business and Carlisle?s own thorough testing, manufacturing and quality procedures. All SA park brakes are subject to testing on an inertia dynamometer, a test which simulates the movement and energy of the intended application vehicle. After successfully completing this dynamic and exacting test, the SA undergoes a battery of endurance tests, including full torque flex, seal and environmental tests. Comprehensive testing is required when SA series park brakes end up on articulated dump trucks, wheel loaders, motor graders, telehandlers and rough terrain cranes, all of which can and do operate in inclement weather and on challenging road systems,? informs Colm Gallagher, Marketing Manager, CIBF.

Twelve years after Carlisle launched the first SA park brake, two more brakes in the SA series are were made available. The SA2500, which possesses lower release pressure and less clamp force, and is the smallest and lightest member of the SA series, is ideal for telehandlers. Additionally, a modified version of the SA7000, a low pressure version, has been added to the product family. The latest SA brake is the SA14000, which, with its dual pods, doubles the clamp load while the release pressure remains the same as the SA7000. The SA14000 is a good fit for articulated dump trucks and rigid construction trucks up to 60 tonne, according to Gallagher.

Carlisle entered the off-highway braking market in 1990 with the acquisition of BF Goodrich?s pioneering off-highway division in Bloomington, Indiana. BF Goodrich created the first braking solutions for large mining vehicles in the 1950s, thereby paving the way for today?s trucks that can in some cases reach weights of 100 tonne with loads of up to 400 tonne. Soon after BF Goodrich produced its first brake for the mining industry, Goodyear, which along the way was bought by first Rockwell and then Arvin Meritor, also entered the off-highway braking market. Carlisle went on to acquire Arvin Meritor?s off-highway braking division in 2005. The resulting merger helped Carlisle grow to be the largest off-highway braking company in the world, boasting unrivaled engineering competencies and a full suite of braking products.

Natarajan further adds, ?Today, Carlisle is solving braking problems for myriad industries, including wind, construction, industrial, agricultural, military, and, of course, mining. Headquartered in Bloomington, Indiana, Carlisle Industrial Brake & Friction employs 300 people worldwide with manufacturing in the US, Wales, China, Japan, and Holland. It also has distribution networks established on all six continents.? ?Over 20 braking and friction engineers work with customers from the brake solution design phase all the way to installation and service on machines. Carlisle employees are able to draw on those decades of experience in braking, friction and hydraulic products, he adds. Recently Carlisle Companies Inc has established its India office. Carlisle Trading and Manufacturing India, a wholly-owned subsidiary of Carlisle Companies Inc will initially focus on India?s growing mining, construction and power sectors. According to Natarajan, the company?s strategy is to establish a local presence to support this growing customer base, and this new office will provide sales, service, design and application engineering services as part of this effort. In addition, Carlisle is making plans to establish a local warehousing and light assembly factory in Chennai in the near future.

Thangadurai Natarajan:

Address: Regus Olympia Tech Park, Level2, Altius, 1-Sidco Industrial Estate, Guindy, Chennai - 600 032, Tamil Nadu, India. Tel: +91 44 4299 4300, Email: tnatarajan@carlisle.com, Web: www.carlislebrake.com Tel: 800 873 6361 (USA) 44 0 1495 767300 (Europe) 91 44 4299 4351 (India)