OK Flux 429 is a neutral, bonded flux intended for butt and fillet welding of carbon and low alloy steel plate.
OK Flux 429 is a neutral, bonded flux intended for butt and fillet welding of carbon and low alloy steel plate. It combines good as welded and stress relieved mechanical properties with excellent performance. Its slag is generally self peeling, even in tight, narrow groove butt welds. It provides moderate tolerance of rust and mill scale. OK Flux 429 is used in offshore oil rig, bridge, ship, pressure vessel, and structural fabrication. It will operate with DC and AC, single and multiwire systems at currents up to 1000 amps.

| Typical Mechanical Properties | |
|---|---|
| As Welded | |
| Spoolarc 81 | |
| Tensile Strength | 79 ksi, 545 MPa |
| Yield Strength | 66 ksi, 455 MPa |
| Elongation in 2" | 28 % |
| CVN | 48 ft.-lbs., 65 J |
| Temperature | -20 °F, -29 °C |
| Spoolarc 40B | |
| Tensile Strength | 88 ksi, 605 MPa |
| Yield Strength | 77 ksi, 530 MPa |
| Elongation in 2" | 25 % |
| CVN | 21 ft.-lbs., 28 J |
| Temperature | -20 °F, -29 °C |
| Spoolarc 29S | |
| Tensile Strength | 83 ksi, 570 MPa |
| Yield Strength | 67 ksi, 460 MPa |
| Elongation in 2" | 27 % |
| CVN | 38 ft.-lbs., 42 J |
| Temperature | -20 °F, -29 °C |
| Spoolarc 53 | |
| Tensile Strength | 85 ksi, 585 MPa |
| Yield Strength | 71 ksi, 490 MPa |
| Elongation in 2" | 28 % |
| CVN | 30 ft.-lbs., 52 J |
| Temperature | -40 °F, -40 °C |
| Spoolarc 75 | |
| Tensile Strength | 86 ksi, 595 MPa |
| Yield Strength | 73 ksi, 505 MPa |
| Elongation in 2" | 28 % |
| CVN | 40 ft.-lbs., 54 J |
| Temperature | -40 °F, -40 °C |
| Spoolarc ENi4 | |
| Tensile Strength | 93 ksi, 640 MPa |
| Yield Strength | 82 ksi, 565 MPa |
| Elongation in 2" | 25 % |
| CVN | 44 ft.-lbs., 60 J |
| Temperature | -40 °F, -40 °C |
| Stress Relieved 1 hr. @ 1150°F | |
| Spoolarc 81 | |
| Tensile Strength | 75 ksi, 515 MPa |
| Yield Strength | 60 ksi, 415 MPa |
| Elongation in 2" | 30 % |
| CVN | 50 ft.-lbs., 68 J |
| Temperature | -40 °F, -40 °C |
| Spoolarc 71 | |
| Tensile Strength | 80 ksi, 550 MPa |
| Yield Strength | 63 ksi, 430 MPa |
| Elongation in 2" | 32 % |
| CVN | 20 ft.-lbs., 28 J |
| Temperature | -20 °F, -29 °C |
| Spoolarc 40B | |
| Tensile Strength | 88 ksi, 605 MPa |
| Yield Strength | 75 ksi, 515 MPa |
| Elongation in 2" | 26 % |
| CVN | 26 ft.-lbs., 35 J |
| Temperature | 0 °F, -18 °C |
| Spoolarc ENi4 | |
| Tensile Strength | 89 ksi, 615 MPa |
| Yield Strength | 77 ksi, 530 MPa |
| Elongation in 2" | 26 % |
| CVN | 24 ft.-lbs., 33 J |
| Temperature | -40 °F, -40 °C |
| Typical Undiluted Weld Metal Analysis | |
| As Welded | |
| Spoolarc 81 | |
| C | 0.06 % |
| Mn | 1.40 % |
| Si | 0.45 % |
| P | 0.020 % |
| S | 0.015 % |
| Spoolarc 40B | |
| C | 0.06 % |
| Mn | 1.40 % |
| Si | 0.40 % |
| P | 0.023 % |
| S | 0.012 % |
| Mo | 0.48 % |
| Cu | 0.48 % |
| Spoolarc 29S | |
| C | 0.07 % |
| Mn | 1.70 % |
| Si | 0.70 % |
| P | 0.020 % |
| S | 0.012 % |
| Spoolarc 53 | |
| C | 0.06 % |
| Mn | 1.80 % |
| Si | 0.50 % |
| P | 0.026 % |
| S | 0.010 % |
| Spoolarc 75 | |
| C | 0.05 % |
| Mn | 1.50 % |
| Si | 0.60 % |
| P | 0.018 % |
| S | 0.012 % |
| Ni | 0.80 % |
| Spoolarc ENi4 | |
| C | 0.06 % |
| Mn | 1.30 % |
| Si | 0.40 % |
| P | 0.021 % |
| S | 0.009 % |
| Cr | 1.7 % |
| Ni | 1.79 % |
| Mo | 0.15 % |
| Cu | 0.15 % |
| Spoolarc 71 | |
| C | 0.06 % |
| Mn | 1.58 % |
| Si | 0.58 % |
| P | 0.018 % |
| S | 0.009 % |
| Basicity Index: | 1.1 |
| Chemical Composition: | |
| SiO2 + TiO2 | 20 |
| Al2 + MnO | 40 |
| CaO + MgO | 25 |
| Fluorides | 10 |
| Flux Consumption | |
| (lb. Flux / lb. Wire) | |
| Voltage | DC+ |
| 26 | 0.73 |
| 30 | 1.02 |
| 34 | 1.33 |
| 38 | 1.46 |
All listed prices are in U.S. dollars and represent the Manufacturer's Suggested Retail Price (MSRP) for sale in the United States. Actual selling price will be determined by the Distributor. Prices are subject to change without notice.