Iveco NEW DAILY, Инструкция по эксплуатации

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NEW DAILY
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APPLICATIONS OF SUPERSTRUCTURES
APPLICATIONS OF SUPERSTRUCTURES
3.3
CONNECTION BETWEEN CHASSIS AND COUNTER CHASSIS
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Printed 603.95.789
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1 Ed. - Base 02/2014
Alternatively, use the connection in Figure 11, using the screws that connect the rear crossbar to the frame.
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In all other cases, it is absolutely forbidden to put holes in the wings.
Connection characteristics
Elastic connections (see Figures 8, 9 and 10) allow limited movement between the chassis and the counter chassis; These connec-
tions make it possible to consider parallel cooperation of the two resistant sections, where each assumes a share of the bending
moment proportional to its moment of inertia.
In the rigid connections (see Figure 11), a single resistant section can be considered for the two profiles, on the condition that the
number and distribution of the connections are such as to withstand the consequent cutting forces.
The possibility of establishing a single resistant section between the chassis and the counter chassis allows you to achieve greater
resistant capacity compared to the connections with brackets or clamps, obtaining the following benefits:
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lower height of the counter chassis profile to equal bending moment acting on the section;
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greater bending moment allowed, equal to the dimensions of the counter chassis profile,
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further increase in the resistance capacity if materials with high mechanical properties are adopted for the counter chassis.
Connection with brackets
Some examples of this type of connection are shown in Figures 8 and 9.
102460
Figure 8
1. Counter chassis
2. Chassis
3. Shims
For the elasticity of the connection it is necessary that, before the closure of the clamping screws the distance between the brack-
ets of the chassis and the counter chassis is 1 ÷ 2 mm; greater distances should be reduced by means of suitable spacers. At the
closure of the screws, brackets must be brought into contact.
The adoption of screws of a suitable length promotes the elasticity of the connection.
The brackets must be fixed to the rib of the side members of the vehicle by means of screws or nails.
In order to better contain the loads in the transverse direction, the brackets are normally applied so that there is a slight protrusion
perpendicular to the upper edge of the chassis. If instead the brackets must be applied exactly to the wire, the side guide for the
superstructure must be assured with other devices (e.g. using guide plates connected only to the counter chassis, or only to the