KT Group Members

Welding Instruction

1. Dry the electrodes at 300-350°C for 30-60 minutes before use.
2. Clean up the contaminations on the work piece. Keep the arc as short as possible.
3. Take the back-step method to prevent porosity at the arc starting.
4. Preheat and the Interpass temperature should be ≥ 200°C.
5. Use high tensile strength low hydrogen electrode for the buffer layer in multi-layer build-up.

Typical Chemical Composition of Weld Metal (wt. %)

C

Si

Mn

Cr

Ni

0.700

1.00

1.00

6.50

1.35

Typical Hardness of Weld Metal

        Hardness

Condition

Vicker’s hardness

（HV）

Rockwell’s hardness

（HRC）

Shore’s hardness

（HS）

As-welded

Interpass temp. ≤150°C

660

58

79

Continuous build-up

630

57

75

Work-hardened

630

56

75

High Temp.

Temperature (°C)

200

300

400

500

600

700

Vicker`s hardness

530

490

440

430

200

100

Size and Suggested Operating Range (AC or DC+)

Diameter x Length(mm)

3.2x350

4.0x350

5.0x350

6.0x400

Amp

70~120

100~170

160~220

200~280