About High-Tensile Steel Sheets Of 980 Mpa Class Or More; Drill Holes For Plug Welding Of Steel Sheet - Subaru Forester 2019 Repair Manual

C: NOTE

1. About high-tensile steel sheets of 980 MPa class or more

To drill high-strength steel sheets of 980 MPa class and 1,500 MPa class, use a tool that can machine objects
of 500 Hv or more hardness (e.g., C-20VR made by Cyuotokenzai).
It is recommended to perform the weldings using 980 MPa class and 1,500 MPa class high-strength steel un-
der the following conditions.
• It is recommended to perform spot welding according to board thickness and number of overlapping
sheets under the following conditions ([a] — [e])
• When conditions can't be met, it is recommended to use the plug welding method [f] — A or [f] — B as de-
scribed below.
Spot welding
Plug welding [f]
CAUTION:
• For new spot welding, avoid previously welded locations.
• After spot welding, inspect the welding locations, and if the weld appears to be insufficient, per-
form plug welding.
• Shape correction by heating and splice welding shall not be performed for components using 980
MPa class or more higher-tensile steel; otherwise this may decrease the strength of the material.

2. Drill holes for plug welding of steel sheet

At locations where spot welding is not possible, use a punch or a drill to open holes for plug welding accord-
ing to the following table.
Plate thickness of the welding material
Less than 1.0 mm (0.04 in)
1.0 mm — 1.6 mm (0.04 — 0.06 in)
1.7 mm — 2.3 mm (0.07 — 0.09 in)
2.4 mm (0.09 in) or more
Compression 4.0 kN
[a] Current 7.5 kA
Welding time 17 cyc
Compression 3.0 kN
[b] Current 8.0 kA
Welding time 23 cyc
Compression 4.0 kN
[c] Current 7.0 kA
Welding time 20 cyc
Compression 4.0 kN
[d] Current 8.0 kA
Welding time 20 cyc
Compression 4.0 kN
[e] Current 8.5 kA
Welding time 20 cyc
Plug diameter 8.5 mm (0.33 in) or more
A Wire YGW12
Gas CO2
Plug diameter 8.5 mm (0.33 in) or more
B Wire YGW16
Gas Gas mixture (argon: 80 %, CO2: 20 %)
Foreword
Plug welding hole diameter
 5.0 mm (0.20 in) or more
 6.5 mm (0.26 in) or more
 8.0 mm (0.31 in) or more
 10.0 mm (0.39 in) or more
BS - 8
Total number of 2 overlapping
sheets
Total number of 3 overlapping
sheets