Main Content Of Door Maintenance - Chery QQ Service Manual

Chery QQ Service Manual Body System
(5) Detect after disassemble. Generally speaking, it includes measurement for geometric
dimensions between sheet metal parts of all kinds, inspect concrete location of damage, make
clear the type of damage, analyze cause of damage, determine maintenance plan.

2.1.3 Main content of door maintenance

Generally speaking, cause of door damage has something to do with the following four aspects:
defect in structural design, defect during the process of production, chemical damage while being
used, physical damage while being used. Main damage causes are introduced as follows:
1. Abrasive wear. Caused by surface friction produced by relative movement because of sheet
metal parts surface touch together and being weighted; for example, door is hanging down,
coordination gap is enlarged because of long time abrasive wear between door hinge hole and
spindle.
2. Corrosion
Oxidizing reaction of sludge-liquid and filth accumulated on surface of the metal; or rust
produced by not adopting preservative treatment after welding repair or corrosion resulted by
touching chemical substance. It occurs frequently in sandwich position and spot welding article
joint .
3 Fissure or rupture
Fissure and rupture when it is serious, caused by sheet metal fatigue in the position of stress
concentration and weak link of structure because sheet metal suffers from internal and external
stress repeatedly.
4 The hollowness and fold damage.
The hollowness means that deformation of elasticity or plasticity because of collision and forcing
of door panel.
5 The crooked and twisted damage. That kind of damage means crooked or twisted damage
because the door undertakes too much burden.
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Chery Automobile Co., Ltd