In assemblies containing bolts of a high property class, resistance to loosening is achieved through the elasticity and taper of the TREP® spring washer. These features promote even distribution of the clamping force and maintenance of constant pressure in the assembled components.
TREP® – Disc Spring Assemblies
- TREP®
- Applications
- Features
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TREP® is designed as an anti-loosening security system for all mechanical bolting connection, which consists of 3 or 4 interdependent smooth tapered spring washers with a metal insert. As a safety element, disc spring assemblies maintains constant tension and clamping force in the joint. Even though slight relaxation may occur, the elastic properties of TREP® ensures that the system can withstand loosening in high-stress applications where residual tension in the bolt is of vital importance, or in another words, completely secure and reliable fastening, no concern about the problem of vibration or loosening.
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In mechanical joints with material pairings and large jumps in stiffness (sheet metal joints made of aluminum, copper, or brass), the spring assembly can counteract a loss of preload force and shows greater resistance to loosening in the presence of applied vibrations than with individual clamping washers.
- Electrical equipment
- Shipbuilding
- Railway
- Heavy vehicles
- Other machines subject to high vibrations
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- Resistance to loosening/unscrewing
- Retains the tension and clamping force
- Better durability, fatigue life test more than 1,000,000 cycles
- Ability to adapt thermal expansion, high temperature resistance
- Corrosion resistance
- Easy assembly saves working time
- TREP plus®
- Applications
- Features
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For soft surfaces such as aluminum, copper or brass, the special solution TREP plus® distributes the clamping force over a larger surface area without slipping.
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The TREP plus® disc spring assembly with the additional washer and large outer diameter effectively bridges the force transmission in oblong holes.
- Electromobility/high-voltage batteries/electrical appliances/transformers.
- Electrically conductive connections/contact glands in the high-voltage range, grounding cables
- Plant and mechanical engineering
- Vehicle construction
- Transport plant construction
- Rail vehicles (e.g., power electronics)
- Motor mountings
- Slotted hole connections, e.g., for adjustments
- Screw connections made of non-ferrous metals with large expansion coefficients e.g., aluminum, copper alloys
- Other applications subject to vibration
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- Reliable pretensioning and securing of contact points for current-carrying connections.
- Operationally safe connections with demands for strength classes ≥ 8.8/≥ A2-70.
- Maintenance of clamping tension between the connected elements
- Uniform distribution of contact pressure
- Universal range of application where settling, thermal expansion must be compensated for
- Easy and safe assembly thanks to the multifunctionality of a component with a slim management
- Improved force transmission through the elongated holes due to enlarged bearing surface
- No surface damage to the bearing surfaces of the bolted components
- Dimensions from M8-M16 for screws