Material Properties
and Impact Insulation
Technical Information

Sylodamp® – an overview
Sylodamp® is a high-damping polyurethane elastomer thathas been specially developed to absorb the loads caused
by impacts. Sylodamp® can also be employed as an elastic
component in conventional vibration insulation applications in which, in addition to permanent elasticity, a highlevel of damping of the elastomer is required. Typical applications can be found in situations where machinery, building structures, technical equipment or even people need tobe protected.
The following benefits have been identified in the area ofimpact and vibration insulation:— Reduces the loads caused by impacts— Reduces impact-induced structure-borne noise— Reduces resonance phenomena— Damping of components or structures— Rapid decay of vibrations
In most cases, Sylodamp® is employed as a pressurised
spring, the material properties of which can be ideallyadapted to the application in hand by the careful choice ofmaterial type, contact area and elastomer thickness.
The Sylodamp® range covers the following static rangesof use:

The static range of use is the maximum compressive
stress defined for stationary loads at which the elastic
properties of an elastomer are permanently retained.
The material type refers to the compressive hardness at
10 % deformation. This is an individually defined measurefor the load-bearing property of an elastomer, but does
not give any information on the behavior during longterm loading. For example, the compressive hardness ofSylodamp® SP 100 is 100 kN/m2.

Vibration insulation with Sylodamp®
Vibration insulation uses the principle of mass force
compensation to reduce the propagation of mechanicalvibrations caused by external forces or excitations. The
principle area of application of Sylomer® and Sylodyn®
materials is in conventional vibration insulation.
Using Sylodamp® enables even higher levels of vibration
insulation to be achieved, especially when the impulsive
loads or strong resonance phenomena that typically occur when machinery is being started up or shut down arepresent.
In addition to the presence of Sylodamp® bedding, a combination of Sylodamp® and Sylomer® springs can also beused in parallel.

SP
1000
SP
500
SP
300
SP
100
SP
30
SP
1010.10.01

Vibration damping with Sylodamp®
Vibration damping is understood to be the conversion of
kinetic energy into another form of (renewable) energythat no longer has any impact on the vibration system.
Due to its high level of material damping, Sylodamp® is aparticularly effective way of keeping the resonance phenomena occurring in components or structures within therequired tolerances.

0.001
Specific load in N/mm2Fig. 1: Sylodamp® range

www.getzner.com

Impact insulation with Sylodamp®
Impact insulation is a special type of vibration insulation that is used to reduce the propagation of the forces
generated by impacts. Here, a brief exciting force witha relatively high peak force is converted into a longer
lasting ground force with a lower peak value.

ds
Sylodamp®
mv

The material damping features of Sylodamp® result in therapid damping of kinetic parameters, reducing the decay
time of components and structures.

Examples of impacts
Figs. 2 to 4 illustrate some examples of impacts in whicha mass m collides with a structure at a velocity v. The
high-damping vibration insulator made from Sylodamp® isshown in orange.

Fig. 3: Horizontal impact – mass moving horizontallyds
Sylodamp®

mv

mFig. 4: Oblique impact – mass moving at an angle

hSylodamp®

vsFig. 2: Vertical impact – free-falling mass

2dm = Mass of the moving bodyv = Impact velocity of the moving massd = Thickness of the elastomers = Maximum deformation of the elastomer
h = Free-fall drop heightDegree of insulation
The impact-insulating effect introduced by the use of elastic bedding can be described by the degree of insulation I.
This is defined as the reduction in the maximum response
loading in an installation with elastic bedding compared toone without:

1IFmax, 0 – Fmax
Fmax, 0I
= Degree of insulation in %F max, 0 = Maximum value of the propagatedground force without elastic bedding
Fmax = Maximum value of the propagatedground force with elastic bedding

Principle of the conservation of energy
The principle of the conservation of energy forms thebasis for the selection of the appropriate material for animpact application. This equates the mechanical impact
energy Ekin (kinetic energy) with the deformation energy
Edef (energy absorption) of the high-damping Sylodamp®
material:

2

Ekinm · v2
23

EkinEdef

Ekin = Impact energy (kinetic energy) in J
Edef = Deformation energy (energy absorption) in J

Material selection
There are two ways of selecting the most suitable materialfor impact applications:— Computational model (finite element method)— Using diagrams showing the energy absorption ofSylodamp®

Finite element method model
For straightforward impact applications, Getzner has
developed a computational FEM model. The material andimpact modelling makes use of drop test stand investigations with high-damping Sylodamp® materials and impactors with impact velocities of up to 5 m/s.
An FEM impact simulation allows the most suitable material design from the Sylodamp® range to be selected forthe application.

Input parameters for the FEM simulation
The following input parameters for the impact simulationmust be known:— Mass of the moving body
— Impact velocity of the body
— The covering of the elastomer surface
to be struck by the impactor— Required elastomer thickness

Results of the FEM simulation
An FEM impact simulation calculates the following results:— Plots against time of ground force, elastomer
deformation, energy absorption and/or brakedelay during the impact— Maximum propagated ground force— Maximum deformation of the elastomer— Maximum brake delay

3

3.0

Deflection in mm

Force in kN

Results of FEM impact simulations
Figs. 5 to 8 show the results of a typical FEM impact simulation with Sylodamp®.

Maximumground force Fmax

2.5
2.0

5Maximum deflection smax

43Recovery

1.5
21.0
Deflection
10.5
000.0050.010

000.015
Time in s

0.010

0.015
Time in s

Fig. 6: Impact simulation – plot against time of deformation

1.5

Energy absorption in J

Speed in m/s

Fig. 5: Impact simulation – plot against time of ground force

0.005

Impact velocity v
1.00.5
Reversal pointat smax

8Maximum energy absorption

640.0
2-0.5
Recovery-0.1
00.0050.010

Fig. 7: Impact simulation – plot against time of velocity of mass

40.015Time in s

000.005

0.010

Fig. 8: Impact simulation – plot against time of energy absorption

0.015
Time in s

1000

Specific energy absorption in mJ/mm2

Specific energy absorption in mJ/mm2

Energy absorption of Sylodamp®
As an alternative to FEM simulations, the choice of the most suitable Sylodamp® material for straightforward impact
applications can also be made using the following diagrams (Figs. 9 to 12).

1001011000

100

1010.1

0.1
2030

40

5060
7080
Linear compression in %204050607080
Linear compression in %Fig. 10: Energy absorption of Sylodamp® – thickness 25 mm

Fig. 9: Energy absorption of Sylodamp® – thickness 12.5 mm

1000

Specific energy absorption in mJ/mm2

Specific energy absorption in mJ/mm2

30100

1010.1

1000

1001010.1
20304050607080
Linear compression in %Fig. 11: Energy absorption of Sylodamp® – thickness 37.5 mm

SP 10

SP 30

SP 100SP 300SP 50020304050607080
Linear compression in %Fig. 12: Energy absorption of Sylodamp® – thickness 50 mm

SP 1000

The impact energy exerted on the elastomer surface
is used as an input parameter when choosing the mostsuitable material design.
The impact velocity has no significant effect on the specific energy absorption of Sylodamp®. The specific energy
capacities shown in the diagrams can be used for impact
velocities of between 0.5 m/s and 5 m/s.

5

Ideal deformation ranges
A corresponding deformation path must be provided forthe elastomer so that Sylodamp® can provide the best
possible absorption of impact loads.

Impact force propagation
The aim of impact insulation is to dissipate the kinetic
energy of the impactor with minimum levels of force overas long a period as possible.

We recommend the following linear compression figureswhen using Sylodamp® in impact applications:

The maximum force propagated during an ideal elastic
impact can be determined from the deformation energy
Edef and the deformation path s:Material type

Ideal deformation range

Sylodamp® SP 10

40 % to 60 %Sylodamp® SP 30

40 % to 60 %Sylodamp® SP 100

35 % to 55 %Sylodamp® SP 300

30 % to 50 %Sylodamp® SP 500

25 % to 45 %Sylodamp® SP 1000

20 % to 40 %4Fmax, 02·EdefsFmax, 0 = Maximum value of propagated ground force in N
Edef= Deformation energy (energy absorption) in Js= Deformation path in m

Tab. 1: Recommended deformation ranges of Sylodamp® under impact loading

The specified deformation ranges of the individual
Sylodamp ® products result in the energy absorption
shown below for the respective elastomer thickness
values:Material type

Energy absorption

Thickness

12.5 mm

25 mm

37.5 mm

50 mm

Sylodamp® SP 10

0.4 to 0.9

1.0 to 1.8

1.6 to 2.9

2.3 to 4

Sylodamp® SP 30

1.4 to 2.6

2.7 to 5

4.4 to 8.2

6.3 to 11

Sylodamp® SP 100

3.5 to 6.3

7 to 13.3

11.9 to 20.6

15 to 26Sylodamp® SP 300

8.8 to 16.8

17.5 to 34.5

25 to 43.5

30 to 50.5

Sylodamp® SP 500

13.9 to 27.5

27.8 to 57.3

43 to 81.3

56.5 to 101

Sylodamp® SP 1000

21 to 44

40 to 95

70 to 140

100 to 200

Tab. 2: Recommended specific energy absorption in mJ/mm2 of Sylodamp®

6In cases where Sylodamp® is being used as the impactinsulating element, the kinetic energy of the impactor isconverted not just by an elastic process, but by damping(dissipation) as well, further reducing the maximum propagated impact force. The maximum propagated force in theabove scenario can be estimated as follows:

5EFmax, 0 ≈ 1,5 · sdef

Fmax, 0 = Maximum value of propagated ground force
with elastic Sylodamp® bedding in N
Edef
= Deformation energy (energy absorption) in Js= Deformation path in m

The elastic portion of the elastomer provides soft cushioning of the impactor, whereas the dissipative portion
ensures that after the impact the bulk of the energy is nolonger available to the system as kinetic energy.
Due to the high levels of material damping provided bySylodamp®, the impactor only rebounds very slightly
following the impact.
The impact resilience of Sylodamp® is around 15 %, whichmeans that 85 % of the kinetic energy of the impactor isdissipated on impact.

Input parameters
Massm = 80 kg

Impact velocity

v = 2 m/s

Impact area

A = 15,625 mm2 (125 mm × 125 mm)

Calculation of impact force for an elastic Sylodamp® beddingm · v280 · 22== 160 J
22Impact energy

Ekin =

Deformation energy

EDef = EKin = 160 J

Specific energy absorption

EDef, A =Elastomer

Sylodamp® SP 100/25 (as per Fig. 10)

Linear compression

ɛ = 50 % (as per Fig. 10)

Max. deformations = ɛ · Material thickness = 50 % · 25 mm = 12.5 mm

Max. impact force with elastic bedding

Fmax, 0 ≈ 1.5 ·Edef
160== 10.24 mJ/mm2
A
15.625

EDef
160= 1.5 · 0.0125
s= 19.2 kN

Calculation of impact force without elastic bedding with the assumption of an elastic
impact with subsoil resilience of 0.5 mm
Resilience of subsoil/max. deformations = 0.5 mm

Max. impact force without elastic bedding

Fmax, 0 = 2 ·EDef
160= 2·= 640 kN
s0.0005

Impact-insulating effect of elastic bedding
Degree of insulation

I=Fmax, 0 – Fmax
Fmax, 0=640 – 19.2
640

= 97 %

Tab. 3: Sample calculation for a impact isulation with Sylodamp®

7

Getzner Vibration Solutions Pty Ltd
Unit 1 Number 2-22
Kirkham Road West,
Keysborough Victoria 3173
Australia

Getzner Werkstoffe GmbHAm Borsigturm 1113507 Berlin
Germany
T +49-30-405034-00
F +49-30-405034-35
info.berlin@getzner.com

Getzner Werkstoffe GmbHMiddle East Regional OfficeAbdul - Hameed Sharaf Str. 114Rimawi Center - Shmeisani
P. O. Box 961294
Amman 11196, Jordan
T +9626-560-7341
F +9626-569-7352
info.amman@getzner.com

Getzner Werkstoffe GmbH
Grünwalder Weg 3282041 Oberhaching
Germany
T +49-89-693500-0
F +49-89-693500-11
info.munich@getzner.com

Getzner India Pvt. Ltd.
1st Floor, Kaivalya
24 Tejas Society, Kothrud
Pune 411038, India
T +91-20-25385195
F +91-20-25385199
info.pune@getzner.com

Getzner Spring Solutions GmbH
Gottlob-Grotz-Str. 174321 Bietigheim-Bissingen
Germany
T +49-7142-91753-0
F +49-7142-91753-50
info.stuttgart@getzner.com

Nihon Getzner K.K.
6-8 Nihonbashi Odenma-cho
Chuo-ku, Tokyo
103-0011, Japan
T +81-3-6842-7072
F +81-3-6842-7062
info.tokyo@getzner.com

Getzner France S.A.S.
Bâtiment Quadrille
19 Rue Jacqueline Auriol
69008 Lyon
FranceT +33-4 72 62 00 16
info.lyon@getzner.com

Getzner Materials (Beijing) Co., Ltd.
No. 905, Tower D, the Vantone Center
No. Jia 6, Chaowai Street, Chaoyang District
10020, Beijing, the P.R.C.
T +86-10-5907-1618
F +86-10-5907-1628
info.beijing@getzner.com

Getzner France S.A.S.
19 Rue Hans List
78290 Croissy-sur-Seine
FranceT +33 1 88 60 77 60

Getzner USA, Inc.
8720 Red Oak Boulevard, Suite 400
Charlotte, NC 28217, USA
T +1-704-966-2132
info.charlotte@getzner.com

www.getzner.com

DB WS SP en © Copyright by Getzner Werkstoffe GmbH l 12-2020
Subject to change without notice.

Getzner Werkstoffe GmbH
Herrenau 56706 Bürs
Austria
T +43-5552-201-0
F +43-5552-201-1899
info.buers@getzner.com