Welding

Table 1: Weldability Guide

Grade Designation	Group Number	Qualifying Notes
XLERPLATE® Structural Grades - AS/NZS 3678
250, 250L15 300, 300L15 350, 350L15 400, 400L15 450 WR350 (AUS TEN)	4 4 5 5 5 5	O H/O H/O H/O H/O H/O
XLERPLATE® Analysis Grades - AS/NZS 3678
A1006 K1042	1 8	O H, SC,SR
XLERPLATE® Boiler & Pressure Vessel Grades
AS 1548 - 7 - 430 AS 1548 - 7 - 460 AS 1548 - 7 - 490 AS 1548 - 5 - 490	4 4 5 5	O O H/O H/O
XLERPLATE® Coil Plate
HA1 HA1006 HA1010 HA200 HA250 HU300, HA300/1 HA350 HW350 HXK15B2B	1 1 1 1 3 3 4 5 8	O O O O O O O H/O H, SC, SR

To find the welding energy input and the preheat temperature required for use with a particular welding process on a particular steel of known thickness, the steps given below should be followed:

Step 1: From Table 1 find the "Group Number" for the steel grade. For joints containing different steels use the higher Group Number.

Step 2: Using Figure 1 calculate the "Combined Thickness" of the joint.

Step 3: From Figure 1 find the closest curve to the intersection of Combined Thickness and Group Number. This curve designates the "Joint Weldability Index Letter".

Step 4: From Figure 2 and using the curve bearing the same Joint Weldability Index Letter found from Step 3, read off the preheat temperature for the welding energy input or vice versa.

Steel Grades and Group Numbers

Qualifying Notes

O - Any electrode type or welding process is satisfactory,
H/O - Hydrogen controlled electrodes, or semi-automatic, or automatic processes are recommended; but rutile or other electrodes may be used.
H - Hydrogen controlled electrodes, or semi-automatic, or automatic processes are essential for good welding.
SC - Slow cooling from welding or preheat temperature is recommended.
SR - Postweld heat treatment (stress relief) is suggested for high quality work, particularly where severe service conditions apply to the component.

Figure 1: Method of establishing Joint Weldability Index (A to L) from Grade Group Number and Joint Combined Thickness

Figure 2: Method of establishing Pre-heat Temperature using Joint Weldability Index Letter and Welding Energy Input

Pre-heat and Energy Input Requirements for
Low Hydrogen Electrodes (EXX15, EXX16, EXX18, EXX28)
Semi-automatic and Automatic Welding Processes.

Pre-heat and Energy input Requirements for Manual Metal
Arc Welding with other than Low Hydrogen Electrodes.

Typical Energy Input Requirements for Various Welding Processes.
(Electrode wire sizes shown in brackets - mm.)

Reproduced from WITA Tech Note 1 with permission.