Generalities on repair instructions
The repair instructions represent a base for the correct and technical maintenance and repair.
The content of the prescribe work procedures is based on the instruction level of the fitter with a complete professional formation and a good knowledge of the products. This expertise is indispensable to carry out jobs described.
Basic conditions to correctly carry out a body repair:
Utilization of original Mercedes-Benz replacement parts.
Strict observation of the Mercedes-Benz directives for body work.
Workshop facilities with special tools and appropriate workshop equipment.
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Indications on occupational protection and safety
With the objective of excluding body injuries, as well as to avoid unnecessary jobs under the influence of the vehicle traffic safety that may have vehicle damage as consequences, these indications are to be read carefully and followed strictly.
Inevitably, it is impossible for Daimler AG to evaluate to the last consequences all the situations of risk of injuries that may arise as consequence. Due to this fact, it becomes extremely necessary that everyone that carries out repair and maintenance work on MB cars is sure of his actions, applying his/her expertise in order that his/her own safety is not put at risk and that the vehicle does not receive any negative influence, chiefly from the technical safety point of view, by the chosen way of repair/maintenance.
Due to this fact, special attention is demanded so that all jobs of the described procedures are carried out considering only the valid directives and prescriptions of the local institutions responsible for the protection of health, accidents and the environment.
Repair of parts
For the repair of body parts and separate parts we recommend the following way of procedure:
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Components
For the repair work following an accident, separate and test the electronic components, the steering and the seat belts.
Air conditioning
Do not do any welding or carry out other similar work processes on the closed air conditioning parts or in its vicinity.
Drilling and sawing
Remove from the risk area, before drilling or sawing, all the electric wires and pipes installed in hollow spaces, as well as covered reservoirs installed (for ex. battery).
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Metal shavings
During or after jobs that produce shavings, do not blow them with compressed air jets, but do remove them with a vacuum cleaner.
Engine and additional aggregates
Before jobs that produce shavings (spherical milling, for instance), cover the engine and the additional aggregates (alternator, electromagnetic couplings, etc. for instance) to prevent damages caused by metal shavings.
Aligning jobs
For the aligning jobs that are not placed in straight line before the traction chain, when the aligning forces do not become efficient on the chassis frame or on the body.
Protect the traction chains against jumps with retaining cables or chains.
Observe the indications on jobs of alignment and correction of shapes, as well as checking the control holes. Should it be necessary, loosen the body from the alignment bench and align again.
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Continuation: Welding and similar processes work
The respective adjustment parameters on the spot welding apparatuses tested, approved and released by Daimler AG are published in the specific WIS for the category P. The parameters are used as basic adjustments of the spot welding apparatuses.
Adjustment data are to be maintained without fail, for reasons of operation strength. A spot welding test is to be carried out before the repair.
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Welding methods, welded joints and traces of welding
Spot welding
Spot welding in a single string
Spot welding in two strings
Spot welding in two displaced strings
Indications on the repair method
The maintenance of damaged body sheet metal counts as the favorable cost measures and time saving and must be given preference in the replacement of assembly groups.
In any case, it should be correctly checked which repair process is the most favorable. The maintenance for the repair should be always considered as the “first option”; with this the strength, the dimensional stability, the anti-corrosive resistance, etc. obtained at the factory, are less influenced.
If the repair is not possible, then are to be observed in the repair, the priorities of type of joints as follows:
1 Spot welding
2 Rivets
3 MAG core welding and other welded joints
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The arc welding with gas protection that are not covered by the assembly parts that are nor found in the visible area or after preparation of the vehicle, for reasons of resistance to operation and of costs, are not to be machined in flat form or must not receive putty.
Means of protection at work
Besides the personal work clothing with protection cap and shoes, also to be utilized during the work according to the needs, protection gloves, protection glasses, hearing protection, masks, etc.
Battery
Before the welding jobs or other jobs that generate sparks in the area of the vehicle battery, this has to be removed and kept in a safe location.
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Helicoidal thread
Metric threads with fault (as from M8) are helical in consonance with the Daimler development area. This is only possible in the tubes that have been produced by the MBN 10349. Tubes diverging from this norm are to be checked for their repair suitability. Further information is found in the KG 00 “Indications on threaded joints with self-molding bolts”.
Vehicles
The vehicles found in the body repair area are to be protected with movable walls or covered with fire-resistant tarpaulin due to the possible destruction of the painted surfaces and glass, as well as the risk of fire by the sparks.
Elevating platform
Due to the parts removed (for ex. engine, axles, etc.) and the weight displacement the vehicle may fall-off the elevating platform. Protect the vehicle or place sand bags for weight compensation.
Anti-corrosive protection
After the painting, the areas affected by the repair are to be treated with an anti-corrosion protection (for ex. wax, sealing of hollow parts, protection of the floorboard when existing).
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Welding smoke
Utilize an exhaust fan in the working area to pull out the health hazardous gases, vapors, dust and welding smoke.
Weldings and similar work processes
For all welding jobs observe the prescription of accidents prevention (UVV) for weldings, re-cuts and similar work processes.
Also, before arc welding jobs, carry out the safety measures for the electronic modules.
Besides, remove from the risk area the flammable substances and liquids and combustible materials. Use protection against sparks and heat jumping, as well as protect the electric wires and installed pipes in the cavities.
For spot welding, maintain approximately 20 mm distance between the spots. Clean and smooth welding rod tips are required. The time of the current or the power has to be adjusted on the spot welding apparatus, relative to the sheet metal thickness (new part).
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Regions of the in series structure
For regions of the structure glued in series, those that are not glued again after an accident repair, is indicated in the respective repair description the quantity of welding spots.
These indications are to be maintained without fail, for reasons of operation strength.
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Strong welding
Arc welding with gas protection
Inter-spaced bead
Solid bead
Solid interrupted bead
Bead in holes
D60.00-0006-09
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Examples of assembly for spot welded instruments