• Mechanical expansion bolts made of high-strength steel enables precise, displacement-controlled, radial preloading

• Designed to user specific requirements

• Expansion controlled by one central pressure bolt

• Compact design

• Operation from one side​

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DESIGN AND FUNCTION

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The threadless expansion bolt was specifically designed for use in threadless bores. Pre-tensioning is achieved through one central pressure bolt. This brand new and market-unique method allows expansion bolts to be mounted more quickly and easily than ever before.

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The threadless expansion bolt typically consists of three main components: the longitudinally slotted conical sleeve, the conical bolt, and the tensioning element, which includes the bolt body, pressure bolt, and T-shaped pressure plate. To connect two coupling flanges, the threadless expansion bolt is inserted as a pre-assembled unit into the bore. Due to the slotted design of the conical sleeve, it has enough flexibility to be inserted effortlessly, even if the bores are slightly misaligned. By tightening the pressure bolt, the conical bolt is driven into the slotted conical sleeve, causing the sleeve to expand and create radial pre-tension.

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The radial pre-tension is applied in a controlled manner, with the rotation angle of the pressure bolt measured by a powered tool. This ensures that the generated radial pre-tension is independent of friction conditions. The powered tool allows the threadless expansion bolt to be preloaded in less than one minute, making it faster than any other expansion bolt. The coupling flanges are precisely aligned by the expansion bolt, allowing them to transmit transverse forces generated by the coupling torque without destructive micro-movements.

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To disassemble the threadless expansion bolt, the pressure bolt is first loosened and removed along with the bolt body and pressure plate from the conical sleeve. Despite the removal of the tensioning element, the radial pre-tension remains, and the conical sleeve stays expanded. The pressure plate exposes a threaded bore, which can be used to pull the conical bolt out of the sleeve. Thanks to the slots, the conical sleeve contracts and can be easily removed from the bore with minimal effort.

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ADVANTAGES

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• Innovative clamping element with just one central pressure bolt enables fast assembly

• Optimum alignment of the components

• Adapts perfectly to the hole thanks to radial expansion

• No costly and time-consuming reworking of drill holes or dowel pins

• Extremely easy handling - even for non-specialist users

• Defined radial preload by means of torque angle tightening with driven screwdriving tool

• Reusable