Metal Mounting
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Metal Mounting Innovation for your future

Metal Mounting I - METAL MOUNTING SYSTEMS 3 III - VIBRACHOC RANGE APPLICATIONS 9 VIBRACHOC RANGE IV.1 Machine tools and impact machinery 10 IV.2 Rotating and vibrating machinery 11 • METALLIC CUSHIONS FOR PIPES 29 OTHER METAL SUSPENSIONS See current price list for availability of items. We reserve the right to modify the design and manufacture of the products and materials described in this The pictures of the products are supplied for information only. - the contract signed by both parties, or the purchase order and the acknowledgement of receipt, - eventually, special or specific...

I - METAL MOUNTING SYSTEMS VIBRACHOC have a range of all steel mountings whose essential element is the “steel cushion” made from compressed woven or knitted stainless steel wire mesh. Metal mounts have considerable mechanical strength as well as high damping characteristics in the order of 10 to 20%, depending on the application. ADVANTAGES Stability. Steel mounts provide stable characteristics and the height under load remains constant with time. Unaffected by corrosion. Steel dampers are unaffected by oil, grease, solvents, adverse weather and corrosive products. Unaffected by...

II - GENERAL INFORMATION ON VIBRATION AND SHOCK Purpose of an elastic suspension An appropriate elastic mount placed between the support and the equipment usually fulfils two functions: G It has an important static role: it provides better load distribution by absorbing certain manufacturing tolerances, thus allowing more reliable, cheaper installation. It has a dynamic role: it provides protection against vibration and shock, considerably reducing the surrounding vibration and increasing the life time of the equipment isolated. Theory Natural frequency An elastic mount characterised by its...

Natural frequency The purpose of a mount is to reduce the transmission of excitation forces between the suspended mass and the foundation. The degree of attenuation obtained depends firstly on the natural frequency of the mount or, more exactly, on the ratio of fe (excitation frequency) to fn (natural frequency). In the simplest case, that of a single degree of freedom (vertical translation), the natural frequency of the mass + isolator without damping and is written: fn = Hz K = Stiffness of isolator in N.m M = Kg Model of an elastic mount K = stiffness e = damping Transmissibility is the...

for fe/fp > √– attenuation improves with lower damping. 2, To limit amplification at resonance while achieving good attenuation, it is necessary to find a good compromise when choosing a damper. G Transmission coefficient ω = 1 λ > Resonance ωo amplitude at resonance which increases as εo decreases. ω – < √ 2, λ < 1 ωo Attenuation (or vibration isolation) region. ω As = increases, λ decreases. ωo εo has very little effect. For an efficient mounting system use: ω a high value of low value of ω0 low value of λ ω0 a high value of ε0 - limited amplification in the resonant region - minor effect...

Attenuation as a function of natural frequency and frequency of excitation (A theoretical graph for a mounting system without damping) Frequency of excitation (tr/mn) oo o o oooo o oooo ooooo • Select the running speed (rpm) or frequency of excitation (Hz) of the equipment to be mounted, • Project a vertical line to intersect with a horizontal line which passes through the natural frequency of the mounting system selected. • Where the two lines intersect, follow a diagonal line to find the level of isolation for the mounting system chosen.

Shock For impact machines like presses, forging hammers, etc, excitation is generated in the form of individual very short-time based shocks. In the same way as for vibration, where the importance of the relationship of fe to fn is paramount in determining the attenuation provided, here it is the fn/fs relationship (fn: natural frequency of the mounting - fs: shock frequency) which as to be considered. We can deduce from these curves that: G to obtain attenuation of a ½ sine shock (T < 1) the fn/fs ratio must be approximately less than 0.30. Beyond this limit the excitation force is...

III - VIBRACHOC RANGE APPLICATIONS Industry: Isolation of rotating machinery. Isolation of machine tools. G Protection of works of art. G G Defence: Protection of vehicle mounted electronics (tanks,shelters, off-road vehicles). Protection of inertial platforms, guidance systems, fire control and command and control electronics. G Protection of missiles, their associated equipment and components. G G Marine and Naval: Suspension of motors, engines, sructures, and exhaust systems. Protection of electronic cabinets. G Discrete acoustics. G G Aerospace: Protection of electronics. Helicopter...

IV - INDUSTRIAL APPLICATIONS OF THE VIBRACHOC RANGE IV.1 Machine tools and impact machinery - Lathes, horizontal and vertical mills, tapping machines, drills, etc. - Hydraulic and mechanical presses, shears, etc. - High speed presses, power hammers, etc. - Printing machinery, textile machinery, etc. Suspension of machine tools For example, lathes, drills, mills, planes, mortise cutters, saws, grinders, nibblers, gear cutter, borers, tapping machines, etc. The machinery is isolated actively (attenuation of the vibration generated by the machine) and passively (the machine is protected from...

IV.2 Rotating and vibrating machinery - Engines, generators sets, compressors, fans, crushers, centrifuges, dryers, pumps, etc. - Sieves, riddles, engine test benches, pipework, etc. Suspension of well balanced rotating machines This category includes most rotating machines, which develop free forces during operation which are quite low in comparison with their mass, such as: generator sets, air conditioning plants, most engines, fans (in clean air), compressors, pumps, etc. The choice of mounting depends mainly on the speed of rotation of the machine and the degree of attenuation required....