Iveco DAILY M.Y. 2012, Инструкция для тренажера

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3-12
FITTING SUPERSCTRUCTURES D
AILY
Base - 02/2012 Printed 603.95.241
Connections between frame and counterframe
3.3.4 Elastic connections
When greater elasticity is required for the connection (e.g. vehicles with highly rigid structure, such as vans, tanks, etc. used on
winding roads or poor conditions or off-road, etc.), the fastenings shown in Figure 3.9 must be used in the area behind the cab. In
other words brackets fitted with silentblocks (1), Belleville washers (2) in line or in parallel or coil springs (3) must be used.
Figure 3.9
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2. Belleville washers
1. Rubber block
3
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3. Coil springs
The characteristics of the elastic element must be suitable for the structure rigidity, the wheelbase and the type of use of the vehicle
(road conditions).
Furthermore:
- rigidity must progressively increase for the fastenings that are closer to the rear part of the chassis;
- the total capacity of the connection must include also shear-resistant fastenings, which must be positioned near the rear
suspension.
Therefore, the first fastening behind the cab must always be performed with one of the solutions shown in Figure 3.9 and this solution
must be repeated also for the following fastening, changing only its rigidity, especially when the vehicle has a long wheelbase.
For example, when using brackets with silentblocks, elements having the same hardness (sh = 83) must be used and assembled
double in the first bracket and single in the following, with M10 screws and tightening torques of 15-18 Nm.
For all types of fastenings, observe the following:
- use materials that ensure good long-term flexible properties;
- provide appropriate instructions for periodic checking;
- retighten the tightening torque if necessary.
Also note:
a) when fitting structures generating high flexing and torqueing moments (e.g. crane behind cab), the sub-frame must have a size
suitable to support them;
b) in versions where the vehicle must be lifted by means of hydraulic stabilizers (e.g. cranes, lifted platforms), the yield of the elastic
element must be limited in order to ensure sufficient support of the sub-frame and to avoid excessive flexing moments on the
original chassis.