Efficient sealing systems in fluid power applications

26 September, 2017

An example of the benefits available can be seen when retaining a bearing into a typical housing found on hydraulic pumps and compressors. Here, the use of Loctite 603 can eliminate the need for a press fit, which sometimes lead to housing cracks and gearbox damage. As a result, it is possible to relax machining tolerances and deliver reliable lifetime operation.

When it comes to liquid gasketing, the advantages over conventional solid gaskets are plentiful. For instance, there is no gasket relaxation and creep, and no surface irregularities to worry about. In addition, there is no gasket displacement, and no flange bowing or deformation. Liquid gasketing provides 100% metal-to-metal contact, ensuring no leakage.

Cost reduction

In a comparison between O-rings and liquid gasketing, the cost reduction per unit (joining flanges in electric motors) is estimated at €6.80 when considering all machining, assembly and material costs. At a typical OEM producing 50,000 electric motors a year, this amounts to an impressive annual saving of €340,000.

In a case example, the use of Loctite 5188 replaced O-rings on a rear cover to pump housing application in Germany. The liquid gasket successfully withstood operational loads without leaks over the product’s lifetime and delivered numerous cost savings for the customer, including reductions in machining, O-ring inventory and assembly.

Thread-lockers are also proving increasingly popular in fluid technology applications. These adhesives fill all voids in a thread to prevent relative movement and loosening through vibration. They lock and seal at the same time, and prevent corrosion.

The use of Loctite 243 thread-locker on a family of quick connect couplings produced in Sweden helped lock and seal the coupling thread with maximum reliability, while still allowing engineers to open the coupling for service when required.

Dedicated thread-sealers provide a seal against fluids that are aggressive or supplied at high pressure. In a case example concerning hydraulic fittings, Loctite 577 came to the rescue of an injection moulding equipment manufacturer in Taiwan that was experiencing leaks as a result of using PTFE tape. A course thread-sealer was required to seal oil pressures of up to 10,000 psi (690 bar). With Loctite 577, a positive seal was obtained to prevent loosening through heat and/or vibration.

As well as adhesion and sealing, Henkel also offers solutions for cleaning, protecting and dosing in fluid technology. Highly-effective water-based and solvent-based Loctite cleaners ensure oils, greases, liquid lubricants and other impairing residues can be removed reliably before adhesives and sealants are applied.

Metal pre-treatment and conversion coating are just as important as thorough cleaning. The functional coatings under Henkel's Bonderite brand range increase corrosion resistance and help to make production processes more efficient and cost-effective.

In conclusion, be it more reliable, cleaner, more energy-efficient, quieter or less costly systems, Henkel’s portfolio allows fluid technology manufacturers to cater effectively to the growing requirements of the market.

www.loctite.co.uk