LW.A Vibration-damping levelling elements Steel base and stem


  • RoHS
  • g8030

Description

Main specifications

Base

Zinc-plated steel.

Damping element

NR rubber, hardness 80 Shore A, black colour, matte finish.

Levelling plate

Zinc-plated steel.

Packing ring

NBR synthetic rubber O-Ring.

Threaded stem

Zinc-plated steel, supplied not assembled.

Nut and washer

Zinc-plated steel.

General information

Features

ELESA vibration-damping levelling elements have been designed to damp vibrations, shocks and noises produced by moving bodies or non-balanced vibrating masses of equipment and machines which can cause:
  • malfunctioning and reduction of the machine lifespan and/or of the adjacent ones;
  • damage to operator's health;
  • noise.

Technical data and guidelines for the choice

  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, that is to say the load that applied to the vibration-damping element produces a deflection of 1.0 mm [N/mm].
  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 graph 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 to every levelling element = 4,000 N; a 80% isolation degree is required;
    • diagram shows that with a 50 Hz disturbing frequency and an isolation degree of 80%, the deflection obtained is 0.6 mm;
    • divide the load applied by the deflection obtained to define the rigidity required, which is 4,000/0.6= 6,666 N/mm;
    • compare the rigidity value obtained (6,666 N/mm) with the values reported in the table. This value is within the rigidity value reported in the table for LW.A-120 (4,000 N/mm) and LW.A-160 (9,000 N/mm). Choose the vibration-damping element with the lower value that is LW.A-120.
    • graph shows that LW.A-120 (4,000 N/mm) deflection is 1mm.
    • by intersecting the deflection value with the disturbing frequency of 50 Hz in the diagram, the isolation degree obtained is 90%.
This value is even greater than the required one; your choice has proved to be correct.

Assembly instructions

  • Put the base of the vibration-damping element under the machine and insert the stem through the hole (not threaded) in the frame of the machine (fig.1)
  • Turn the square end of the stem to take the levelling plate in contact with the machine thus obtaining the levelling required. Then lock with nut and washer (fig.2)
Vibration-damping levelling elements Steel base and stem LW.A
LW.A
Filter
Code Description D d D1 l L1
min÷max
l l1 d2 s Max. limit static load
[N]
Stiffness
[N/mm]
Max. deflection
[mm]
Weight
415111 LW.A-80-M12x1.25x120 80 M12x1.25 72 133 35÷46 18.5 32 60 7x7 5000 2500 2 530
415121 LW.A-120-M16x1.5x130 120 M16x1.5 109 144 40÷51 23 36.5 80 9x9 10000 4000 2.5 1200
415131 LW.A-160-M20x1.5x170 160 M20x1.5 150 188 50÷63 29 43.5 130 12x12 20000 9000 2.2 2650
415141 LW.A-200-M20x1.5x170 200 M20x1.5 186 198 60÷73 36 54.5 130 12x12 40000 15000 2.7 4500