DVA Vibration-damping elements technical informations Base - DVA: glossy zinc-plated steel. - DVA-SST: AISI 304 stainless steel. Vibration-damping body Natural rubber NR, hardness 555 Shore A, black colour. Standard executions - DVA.1: glossy zinc-plated steel threaded studs. - DVA.1-SST: AISI 304 stainless steel threaded studs. - DVA.2: thredead stud and boss in glossy zinc-plated steel, threaded blind hole. - DVA.2-SST: thredead stud and boss in AISI 304 stainless steel, threaded blind hole. - DVA.3: glossy zinc-plated steel bosses, threaded blind hole. - DVA.3-SST: AISI 304 stainless steel bosses, threaded blind hole. - DVA.4: glossy zinc-plated steel threaded stud. - DVA.4-SST: AISI 304 stainless steel threaded stud. - DVA.5: glossy zinc-plated steel boss, threaded blind hole. - DVA.5-SST: AISI 304 stainless steel boss, threaded blind hole. - DVA.6: glossy zinc-plated steel threaded stud. - DVA.6-SST: AISI 304 stainless steel threaded stud. - DVA.7: glossy zinc-plated steel boss, threaded blind hole. - DVA.7-SST: AISI 304 stainless steel boss, threaded blind hole. Special executions on request - Natural rubber NR, hardness 405 Shore A. - Natural rubber NR, hardness 705 Shore A. Features and applications Elesa+Ganter vibration-damping elements have been designed to damp vibrations, shocks and noises produced by moving bodies or vibrating masses which can cause: - malfunctioning and reduction of the machine lifespan and/or of the adjacent ones - noise - damage to mens health. Technical data and guidelines for the choise 1) Basic data required: - disturbing frequency: the frequency of the disturbing vibration produced by a on-duty machine. In general, it is obtained by the number of rotations of the engine Hz=r.p.m./60 - the load applied to every single vibration-damping element N - the isolation degree required % - the deflection value of the vibration-damping element under a given load mm - the rigidity N/mm , that is to say the load that applied to the vibration-damping element produces a deflection of 1.0 mm. For DVA.6 and DVA.7 the non-linear progress of the rigidity as reported in the graphs. 2) How to choose the vibration-damping element: - with reference to the diagram for checking the isolation degree, intersect the disturbing frequency value with the isolation degree required (each isolation degree corresponds to a line in the diagram) and define the deflection in mm - divide the load applied onto the vibration-damping element by the deflection value to obtain the required rigidity of the vibration-damping element - compare the rigidity obtained with the rigidity shown in the table and choose the vibration-damping element which presents the nearest value (lower) to the calculated one. 3) Check: - the deflection of the vibration-damping element chosen can be obtained in the graphs (DVA.6-DVA.7) on the basis of the load - intersect the disturbing frequency value with the vibration-damping element deflection value in the diagram to obtain the isolation degree offered by the vibration-damping element chosen - compare the obtained value with the isolation degree required. 4) Example: Conditions of use: - disturbing frequency= 50 Hz (3,000 r.p.m.) - load applied on each vibration-damping element 120 N - 90% isolation required - diagram shows that with a 50 Hz disturbing frequency and an isolation degree of 90%, the deflection obtained is 1.0 mm - divide the load applied by the deflection obtained to define the rigidity required, which is 120/1.0 = 120 N/mm - compare the rigidity value obtained (120 N/mm) with the values reported in the table - the values reported in table, for type DVA.1, show that the vibration-damping element which should be used is DVA.1-25-20- M6-18-55.