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 (182 Ko)
Any mechanical assembly is built of parts manufactured to specified machining tolerances. In a complex assembly of several hundred or thousand parts these tolerances soon add up. Unpredictable and undesirable clearances will generally be discovered once the assembly is completed. Bad fit leads to harsh wear and tear in use and early, possibly catastrophic mechanical failure.
Before the invention of laminated shims engineers had resort to one of two possible solutions (which have today been rendered obsolete).
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First Method :
Grinded Adjustment Shims |
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Second Method :
Solid Shims |
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Principle : after measuring the clearance which demands compensation, technicians must individually grind down oversize spacers until they finally correspond to the missing dimensions. These accessories are named adjustment shims.
Disadvantage : the manufacturing process is a highly skilled, time intensive and costly operation. It requires the provision of a grinding machine and generally implies an outage of the production line. |
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Principle : technicians make a stack of metal plates which are inserted into the ailing mechanism.
Disadvantage : this method risks dangerous imprecision. It is very easy to accumulate dust, grease or material fragments as the metal plates are stacked. The quality of the final result remains very uncertain. |
| The LAMECO Solution :
Laminated Shims | |
LAMECO offers a third solution, the superior technology-oriented solution: the Laminated Shim.
Principle : precision manufactured from metals or high technology composites* which have the property of being easily peelable into micro fine strips of a few hundredths of a millimeter. |
An extremely fine resin film (in the order of 0.00008” / 0.002 mm) is laid out between the material foils. A combination of enormous pressure and a prolonged thermal treatment bonds the sandwiched materials together.
By this long developed proprietary technique not only is the optimal hardening of the resin is achieved, but also the adhesive film's thickness is reduced to such proportions that it can no longer be measured.
Use Factors : (147 ko)
New to laminated shims? Or maybe just wondering which type would best meet your requirements?
There are two key issues to be born in mind:
| First factor :
Maximum use temperature |
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Second factor :
Mechanical stress |
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It should be born in mind that the special binder film is extremely fine. After thermal treatment its thickness can be virtually discounted it is so thin.
But above 446°F (230°C), the binder will be destroyed. However, its disappearance does not influence in any way the continued use of the LAMECO shim. The part will continue to work until it is replaced during the maintenace disassemblies.
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You must first know what pressure and stress will be exerted on the laminated material.
You must avoid situations where shim faces would be submitted to friction - there will be a risk of de-lamination unless you specify a PTFE treatment.
If your parts are provided with fixation holes, the only pressure will be that exerted by the tightening of fixing screws. This is only a small pressure. In this case all LAMECO laminated materialscan be used without any limitations.
For all other cases, please refer to the following table.
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Temperature/
Mechanical Stresses |
Less than 302°F (150°C) / no pressure |
Less than 302°F (150°C) / with pressure |
More than 302°F (150°C) / no pressure |
More than 302°F (150°C) / with pressure |
Aluminum
Pressure Resistance =
14,223 psi* (10 kg/mm2) |
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√ |
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Brass
Pressure Resistance =
64,005 psi* (45 kg/mm2) |
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√ |
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INTERCOMPOSITE®
Pressure Resistance =
28,446 psi* (20 kg/mm2) |
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√ |
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Stainless Steel
Pressure Resistance =
99,563 psi* (70 kg/mm2) |
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Stainless Steel SILENTLINE®
Pressure Resistance =
113,786 psi* (80 kg/mm2) |
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√ |
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Steel
Pressure Resistance =
120,898 psi* (85 kg/mm2) |
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√ |
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Steel SILENTLINE ®
Pressure Resistance =
135,121 psi* (95 kg/mm2) |
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√ |
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X.FIBER®
Pressure Resistance =
56,893 psi* (40 kg/mm2) |
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*psi
= pound / square inch
Once you have taken these two factors into account, you can choose which material best suits your requirements by considering the following points:
| Is LIGHTNESS a primary factor? |
If weight reduction is your primary concern (for portability, or more useful carrying capacity, etc.) :
INTERCOMPOSITE® and X.FIBER® would be perfectly suited to your needs.
They are best recommended as they are the lightest of our products. INTERCOMPOSITE® has an excellent weight/mechanical characteristic ratio whenever minimum weight and outstanding performance are demanded together .
X.FIBER® is EVEN stronger and can be used as a fine replacement for carbon or stainless steels .
An extra plus with these products is that both INTERCOMPOSITE® and X.FIBER® can be easily peeled with forefinger alone - no tools required!
INTERCOMPOSITE® is not only very fast to use, but is the least expensive of all laminated materials.
Find more information on INTERCOMPOSITE® or X.FIBER®.
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| Does your assembly have 'DIFFICULT' shapes? CURVED profiles? |
| If you want to wedge on curved shapes, you have to choose
INTERCOMPOSITE®. This
material can be quickly and easily adapted to most curves without any loss of utility or precision.
Please visit this page for more information.
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| Would NOISE REDUCTION prove a useful asset? |
| If you are inserting laminated shims into systems or machines whose operation is noisy due to considerable vibrations: choose SILENTLINE®. This laminated material, said “ silent ”, has the property of dispersing, in emission duration and amplitude, over 50% of the harmful frequencies.
SILENTLINE® is also the most resistant of LAMECO's special shims. Please visit this page for more information.
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| Two final hints: |
| Steel is best avoided in assemblies presenting a corrosion risk.
It is better to avoid aluminum, whenever productivity improvement is being sought. The peeling of aluminum is namely more delicate, therefore longer.
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Bearing in mind the temperature at which the shim will be performing, the
mechanical stresses exerted, the possible benefits of noise reduction, the presence of difficult curved mating surfaces, or the desirability to save weight in your final assembly should guide you to selecting the correct LAMECO laminated shim for your precise application.
Once the
material has been set out, avoid planning said "solid" parts (or "S.P.") in strong thicknesses. For in contrast to what one would be
led into thinking, by thus inserting solid parts, the shim mechanical qualities are being lowered. Moreover, the shim price is substantially increased since the
shims require a delicate machining (for instance tool jumping at sliding feed). The more so as they belong to the class of special manufacturings without available stock.
Consequently, the solid part will be used only in case of special technical constraint. This notably occurs whenever it is necessary
to carry out a threaded portion within the shim or chamfer thickness.
You can use our enquiry's form
here.Or you can send us an e-mail :
sales@LamecoGroup.com
*,or a fax, Lameco Usa : 310 496 4271 - Lameco : + 33 / (0)1 30 68 14 47*.
*Since 99% of LAMECO shims are manufactured according to our client's drawings. Please provide the following details for an accurate quote:
1 Drawings (not necessary for simple shims)
2 Dimensions
3 Materials
4 Total thickness of shims
5 Thickness of each lamination
6 Quantities |
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You can send us your
information like as following :
| 1 |
2 |
3 |
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4 |
5 |
Square : |
8" x 8" |
Intercomposite® |
Thickness : |
.08 / |
.0004 |
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Rectangle : |
5'' x 7'' |
Steel Silentline® |
Thickness : |
.09 / |
.002 |
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Washer : |
Ø80 X Ø40 |
Stainless |
Thickness : |
.16 / |
.003 |
| 1 = Geometric shape |
4 = Total Thickness of shims |
| 2 = Dimensions (Øexternal X Øinternal) |
5 = Thickness of each lamination |
| 3 = Material |
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