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NO-MAINTENANCE slip joints that combine tough low-friction composite materials with durable metal facings are being custom-fabricated by Hercules Engineering to provide extended lifespan protection against cracking and structural disruption of civil, industrial and resources infrastructure and construction projects.

The composite slip joints (HSCs) complement existing proven Hercuslip stock types, which protect against potentially damaging expansion, contraction, ambient vibration and changing loadings caused by factors such as passing road and rail traffic, production machinery and changing uses of buildings, promises the manufacturer.

Different types of HSC slip joints are located between walls, corbels, beams and concrete floors to provide industrial and commercial engineers, architects and building specifiers with safety- oriented alternatives to more costly types of bearings, or those with shorter lifespans, says David Booty, Manager, Hercules Engineering (a division of Cut To Size Plastics).

“The HSC’s Stainless-Steel Plate (2b Finish) and elastomeric pad slip joint structure typically outlasts standard grease-type slip joints multiple times, providing extended lifespan protection for major infrastructure, industrial and mining projects where no-maintenance durability is vital. The slip joints have been proven in service over lifespans of decades,” says Booty.

“One of the latest applications of custom engineered HSCs involved an underground infrastructure project in which core filled block walls incorporated locating dowels to lock the slab in position and allow for expansion, rotation and shock absorption after the slab is cured.”

CHALLENGE AND SOLUTION

“The challenge involved in ensuring the ongoing slip joint protection required for the project was that cutting or drilling stock slip joints to fit around or between the dowels would have compromised their extremely long-life performance, which was one of their major advantages for the job.

“So, in this case the solution was custom- engineering HSC slip joints to fit in continuous strips either side of the locating dowels so it could be used in extended lengths to provide optimum load-bearing capacity and reliability in a restricted space. This configuration also obtained the greatest benefit from the ability of the extended slip joint to accommodate small variations in the surfaces of the slab and wall structure, with the 7mm thick slip joint acting to accommodate these variations and spread the load evenly to further contribute to greater reliability and lifespan.

“The custom design obviated the need to drill the Grease Slipjoints or to painstakingly and precisely measure the distances between the dowels to use increments of HSC Slipjoints. Using the full length of HSC slip joints on both sides of dowels saves significant amounts of installation time,” says Booty.

Hercules Engineering’s technical brochure will assist in specifying technologies such as Hercuslip joints and complementary Herculon ranges of structural bearings. The document includes recommended slip joint solutions for optimum cost- efficiency and durability for buildings ranging from hospitals and shopping centres, carparks, transport terminals, office towers and warehouses through to factories, storage tanks, silos, boilers and industrial and resources plant such as pipelines, conveyors, pressure vessels and processing facilities across a diverse range of industry. Included is advice for technologies required for different types of structures located across areas of widely differing climatic and geographic diversity.