Cylindrical viscous damper Cylindrical viscous damper, cost-effective simple device Advantages Durable viscous shear damper. Compact and cylindrical geometry provides installation flexibility. It is effective for absorbing a wide range of vibrations, from wind vibration to violent shaking caused by strong earthquakes. Simple structure contributes to cost saving and reduces mechanical problems. Seal free design relieves worry about leakage. Structure and Function CVD, a damper using the shearing resistance of a viscous fluid, consists of three concentric steel tubes filled with viscous fluid. Oiles viscous fluid Oiles viscous fluid is a high viscosity material, which has superior heat resistance, environmental resistance, as well as durability. It provides a stable resisting force during cyclic shearing without viscosity degradation. Basic Features This chart shows the relationship between resistance and displacement when the CVD is subjected to the displacemnet expected during a major earthquake, verifying the stable performance of the device. Performance Axial resistance Force of CVD can be expressed as shown in the formula. Test results Results show the design model coincide with actual measurement, demonstrating stability and accuracy of the design method. Standard dimension of CVD (draft) Resistance force of CVD is calculated by multiplying resistance per unit length by the attachable length of the CVD. Stroke can be changed. Contact us for more information. Type Outside diameter D2 (mm) Clearance d (cm) Stroke A (cm) Resistance per unit length F20 (kN) For 4 m effective length Attachable length L1 (mm) Shearing area S (cm2) Resistance force F20 (kN) Weight (kg) CVD-200 241 0.3 ± 6.0 121.5 4942 45503 486.1 661.4 CVD-250 299 0.3 ± 6.0 171.3 5159 58597 685.0 825.6 CVD-300 340 0.3 ± 6.0 189.9 5161 71113 759.5 990.9 CVD-350 400 0.3 ± 6.0 230.1 5263 85376 920.2 1167.0 Damping forces shown were obtained with a viscous fluid temperature of 20 °C and speed of 10 cm/sec. The values of attachable length and effective length are examples. Contact us for further information.