Compact Spring Return Hydraulic Bolt Tensioner for M20-M22 Ts1

Tightening (Torquing): Uses rotational force (torque) to turn a nut. Most energy is lost to friction between threads and the nut face, making it less accurate. Tensioning: Uses direct hydraulic pressure to pull and stretch the bolt axially. Since the nut is turned down after the bolt is stretched, friction is eliminated, resulting in much higher preload accuracy.

Fluid Leaks: The most common sign; check for oil seeping from the seals or couplings. Piston Issues: If the piston is stuck, does not return fully, or shows a jerky movement, it usually indicates internal seal failure or debris. Coupler Failure: If the hydraulic hose connection fails to hold pressure or is blocked. Physical Damage: Visible cracks, deformation in the bridge or puller bar, or stripped threads on the puller bar.

To achieve a highly accurate and consistent clamping load (preload) on critical fasteners. It ensures uniform gasket compression in large flanges and eliminates the "torsional wind-up" (twisting) that occurs during torque tightening.

For critical, large-scale joints (like wind turbines or high-pressure pipelines), a bolt tensioner is superior because it provides higher precision and eliminates friction errors. For small bolts, tight spaces, or general maintenance, a torque wrench is better because it is more portable, cost-effective, and easier to use.

Torque Check: Using a calibrated torque wrench to see if the nut moves at the target torque. Ultrasonic Measurement: Measuring the change in the physical length of the bolt using ultrasonic waves, which is the most accurate method. Marking: Using paint or a marker to draw a line across the nut and flange to visually check for rotation or loosening over time.