Mitsubishi Evolution X. Manual - part 33

ULTRA HIGH STRENGTH STEEL PLATE

TSB Revision

WELDED PANEL REPLACEMENT

3-2

ULTRA HIGH STRENGTH STEEL PLATE

M4030002800073

ADVANTAGES OF ULTRA HIGH 
STRENGTH STEEL PLATE

The ultra high strength steel plate has the following 
advantages as compared with conventional high 
strength steel plate.

• It has tensile strength approximately 1.7 times 

higher than the conventional high strength steel 
sheet.

• It has a higher yielding point and yielding ratio 

(yielding point/tensile strength).

These advantages allow thinner and lighter plates 
and better fuel efficiency than the high strength steel 
plate.

PRECAUTION UPON MAINTENANCE OF 
ULTRA HIGH STRENGTH STEEL PLATE

• Use a spot cutter for ultra high strength steel 

plate to ensure that the spot-welded area is cut 
off.

• For the part in which the ultra high strength steel 

plate is used, do not repair it by cutting and bond-
ing to avoid the reduction in strength by heat. 
Instead, replace the whole assembly including 
the part.

• Be careful with rough extending work, because 

the ultra high strength steel plate has higher ten-
sile strength and a higher yielding point than high 
strength steel plate and general steel plate. Care-
less work will cause symptom such as over-pull-
ing and springback. Do not extend it completely 
at a time. Do it gradually while removing the dis-
tortion by sheet metal processing with a hammer.

• Plug welding of φ 8 mm (0.31 inch) diameter plug 

for repair ensures the strength equivalent to spot 
welding for 2 steel sheets. For 3 sheets, weld 2 
sheets each time instead of welding from one 
side to give sufficient welding strength.

FRONT END CROSSMEMBER

TSB Revision

WELDED PANEL REPLACEMENT

3-3

FRONT END CROSSMEMBER

M4030003100237

AB700420

AB

Symbol

Operation description

Spot welding

MIG plug welding      : indicates two panels to be welded
                                  : indicates three panels to be welded

MIG spot welding

MIG arc welding (continuous)

Braze welding

Anti-corrosion agent application locations
(Use access holes to apply liberally to butt-welded joints.)

(                                                               )

AB601317

A

A

B

AB

B

REPAIR WELDS

FENDER SHIELD

TSB Revision

WELDED PANEL REPLACEMENT

3-4

FENDER SHIELD

M4030004001203

NOTE: Refer to the Front End Crossmember section on 

P.3-3

 for the welding point with front end crossmem-

ber.

AB700421

AB

Symbol

Operation description

Spot welding

MIG plug welding      : indicates two panels to be welded
                                  : indicates three panels to be welded

MIG spot welding

MIG arc welding (continuous)

Braze welding

Anti-corrosion agent application locations
(Use access holes to apply liberally to butt-welded joints.)

(                                                               )

AB700993

A

AB

A

I

REPAIR WELDS

FENDER SHIELD

TSB Revision

WELDED PANEL REPLACEMENT

3-5

AB700994

J

E

C

F

B

AB

B

G

C

H

D