AWS 7018A1 H4R

Description

Outstanding welding electrode for welding the 0.50% Molybdenum steel and other low alloy steels. The coating is specially formulated to resist moisture pick-up of high heat and humidity. Offers resistance to moisture reabsorption which helps prevent hydrogen cracking and aids in elimination of starting porosity.

Applications

Welding Positions:

Single and multiple pass, DCEP, AC

• Pressure vessels

Category

Low Alloy Electrodes

Industries

Construction and boiler maintenance, piping, tubing

FEATURES

●Low moisture pick-up
●Low hydrogen, less than 4 ml/100 g
●Quick and easy slag removal
●Low spatter level
●Good arc characteristics

BENEFITS

●Prevents starting porosity
●Resistant to hydrogen-induced cracking
●Reduces clean-up time
●Improves weld bead appearance, higher deposition
●Stable, easy to control arc

TYPE OF CURRENT

Direct Current Electrode Positive (DCEP) or AC

RECOMMENDED WELDING TECHNIQUES

GENERAL: Electrode positive, work negative (DCEP) or AC
ARC LENGTH: Very short arc
FLAT: Angle electrode 10°-15° from 90°
VERTICAL-UP: Use weaving techniques
VERTICAL-DOWN: Not recommended
OVERHEAD: Use slight weaving motion within the puddle

STORAGE

After opening, store in holding oven (220°F to 350°F) until used.

TYPICAL WELD METAL PROPERTIES* (Chem Pad)

TYPICAL DEPOSITION DATA (at optimum)

TYPICAL MECHANICAL PROPERTIES* (SR) (1150°F for 1 hr.)

TYPICAL DIFFUSIBLE HYDROGEN

• Maintaining a proper welding procedure - including pre-heat and interpass temperatures - may be critical
depending on the type and thickness of steel being welded.

CONFORMANCES AND APPROVALS

• AWS A5.5, E7018A1 H4R
• ASME SFA 5.5, F-4, A-2, E7018-A1

• ABS E7018-A1

RECONDITIONING

If exposed to atmosphere for extended periods, reconditioned for one (1) hour at 600°F.

TYPICAL CHARPY V-NOTCH IMPACT VALUES*

Not required

STANDARD DIAMETERS AND PACKAGES