Description and Applications
HJ300B is a low hydrogen type electrode. The hardness of deposited metal is approximately HV330 Vickers as welded. Machining is applicable in general.

For surfacing machine parts, such as the shaft, spindles, rollers gears, and carbon and cast steel that are difficult to weld.

Guideline in Usage

1. Preheat at more than 150℃

Keep the arc as short as possible.


Electrodes should be re-dried at 300350℃ for 60 minutes before using.


Remove dirt such as oil and dust from the grooves.

Typical Chemical Composition of Weld Metal(%)
C Si Mn P S Cr
0.08 0.10 4.20 0.015 0.0110 1.08
Typical Hardness of Weld Metal (Vickers Hardness)
As Welded After Work Hardening
295 406
Size & Recommended Current RangeAC
Diameter (mm)
3.2 4.0 5.0
Length (mm) 
350 400 450
Current (Amp) F 100~140 140~190 180~230
V. OH 90120 120170