Unitized Structural Body Repair
Study online at https://quizlet.com/_1fj95j
1. Unibody Lightweight stamped sheet metal components that are welded to each other to
create a single unit.
2. Space Frame Body panels can be made from plastic are steel. Steel may be Mild, Intermediate,
or HSS. Panels may hide damage to frame or structure.
3. Crush Zones Structural components such as rails are designed to collapse and bend at specific
points.
4. Collision Energy Goal is passenger protection. Front and rear structures act as crush-able energy
Management absorbers.
5. Direct Damage POI. Easily located and diagnosed.
6. Indirect Damage transmission of collision energy beyond the area of immediate impact. Examples;
Split seam sealers, pulled spot welds, misaligned panels, buckles in steel, cracked
glass, and cracked or chipped paint.
7. Passive Restraint Must have service manual. No two are alike.
Systems
8. Datum Imaginary plane or line beneath the vehicle. Measures height.
9. Centerline Vertical plane that passes from the front of the vehicle to the rear. Measures Width.
May have stamped marks on vehicle body structure. Is confirmed by referencing
at last 3 width measurements in the undamaged portion of the vehicle.
10. Zero Planes Vertical plane that passes from side to side. Confirmed by measuring 3 length
measurements from the undamaged portion of the vehicle.
11. Symmetry Equal on each side of the vehicle.
12. Asymmetrical Unequal on each side of the vehicle. (spare tire well)
13. Reference Points
1/9
, Unitized Structural Body Repair
Study online at https://quizlet.com/_1fj95j
Bolts or nuts, Holes, Mechanical attachment points, Edges of panels, Door strikers,
Corner of openings. Common tolerance is =/.3mm (1/8) or all the way to 1mm
(1.32).
14. Loaded Measure- Drivetrain In
ments
15. Unloaded Mea- Drivetrain out
surements
16. Point to Point shortest distance between 2 reference points. AKA "as the crow flies". Uses tram or
Measurements steel tape measure.
17. Datum Measure- Taken at Datum plane, height differences between reference points. Laser mea-
ments suring system
18. Computerized compare data stored in a software program or a central database. Get hard copy
Measuring of measurements. Can watch while pulling.
System
19. Steel Cannot know what kind by visible. Must check service manual.
20. Tensile Strength Amount of pressure/force necessary to fracture or tear steel.
21. Yield Strength Amount of force/pressure necessary to deform steel permanently.
22. PSI Pounds per inch /// tensile and yield strengths are expressed. Higher the number
the stronger the steel.
23. Mild Steel Cosmetic, used on Space frames, May be stressed relieved with heat, tears can be
welded without a loss of strength. Yield strength 30,000 PSI
24. Intermediate Yield strength 30,000-70,000 PSI, structural and cosmetic, may be affected by
Steel excessive heat, small tears can be welded w/o loss of strength.
2/9
Study online at https://quizlet.com/_1fj95j
1. Unibody Lightweight stamped sheet metal components that are welded to each other to
create a single unit.
2. Space Frame Body panels can be made from plastic are steel. Steel may be Mild, Intermediate,
or HSS. Panels may hide damage to frame or structure.
3. Crush Zones Structural components such as rails are designed to collapse and bend at specific
points.
4. Collision Energy Goal is passenger protection. Front and rear structures act as crush-able energy
Management absorbers.
5. Direct Damage POI. Easily located and diagnosed.
6. Indirect Damage transmission of collision energy beyond the area of immediate impact. Examples;
Split seam sealers, pulled spot welds, misaligned panels, buckles in steel, cracked
glass, and cracked or chipped paint.
7. Passive Restraint Must have service manual. No two are alike.
Systems
8. Datum Imaginary plane or line beneath the vehicle. Measures height.
9. Centerline Vertical plane that passes from the front of the vehicle to the rear. Measures Width.
May have stamped marks on vehicle body structure. Is confirmed by referencing
at last 3 width measurements in the undamaged portion of the vehicle.
10. Zero Planes Vertical plane that passes from side to side. Confirmed by measuring 3 length
measurements from the undamaged portion of the vehicle.
11. Symmetry Equal on each side of the vehicle.
12. Asymmetrical Unequal on each side of the vehicle. (spare tire well)
13. Reference Points
1/9
, Unitized Structural Body Repair
Study online at https://quizlet.com/_1fj95j
Bolts or nuts, Holes, Mechanical attachment points, Edges of panels, Door strikers,
Corner of openings. Common tolerance is =/.3mm (1/8) or all the way to 1mm
(1.32).
14. Loaded Measure- Drivetrain In
ments
15. Unloaded Mea- Drivetrain out
surements
16. Point to Point shortest distance between 2 reference points. AKA "as the crow flies". Uses tram or
Measurements steel tape measure.
17. Datum Measure- Taken at Datum plane, height differences between reference points. Laser mea-
ments suring system
18. Computerized compare data stored in a software program or a central database. Get hard copy
Measuring of measurements. Can watch while pulling.
System
19. Steel Cannot know what kind by visible. Must check service manual.
20. Tensile Strength Amount of pressure/force necessary to fracture or tear steel.
21. Yield Strength Amount of force/pressure necessary to deform steel permanently.
22. PSI Pounds per inch /// tensile and yield strengths are expressed. Higher the number
the stronger the steel.
23. Mild Steel Cosmetic, used on Space frames, May be stressed relieved with heat, tears can be
welded without a loss of strength. Yield strength 30,000 PSI
24. Intermediate Yield strength 30,000-70,000 PSI, structural and cosmetic, may be affected by
Steel excessive heat, small tears can be welded w/o loss of strength.
2/9
