DH-280: 280A IGBT Rebar Butt Welding Machine — Construction Steel Bar Welder
DH-280
280A Rebar Butt Welding Machine
Part of the Custom Power Supplies product line. Designed and manufactured in Qingdao, China with IGBT inverter technology for reliable industrial performance. CE certified for global export.
Typical Applications: Construction rebar butt welding
DH-280 Rebar Butt Welder
The DH-280 is a 280A DC power supply specifically designed for flash-butt welding of reinforcing steel bars (rebar) in construction applications. Operating from a 380V three-phase input, this IGBT inverter-based machine delivers precisely controlled, high-current pulses for joining rebar diameters from 10 mm to 25 mm in end-to-end butt joints. The DH-280 is a specialised DC power source used as the electrical supply for rebar butt welding fixtures — it provides the controlled welding current while the mechanical clamping and upset forging are handled by a separate hydraulic or manual welding clamp assembly.
Rebar butt welding (also known as flash-butt welding or resistance butt welding) is the preferred method for joining reinforcing bars in cast-in-place concrete structures, precast elements, and bridge construction. Unlike lapped splices or mechanical couplers, a properly executed butt weld produces a full-cross-section joint with tensile strength equal to or exceeding the parent rebar. The DH-280 uses microprocessor-controlled current ramping with programmable preheat, flash, and upset forging phases, ensuring consistent weld quality across varying rebar grades (B400, B500, B600) regardless of operator skill level. The machine is built for site conditions: a sealed control panel (IP22S), a reinforced steel chassis with lifting eyes, and a 60% duty cycle at full rated output.
Detailed Specs — DH-280
| Parameter | Specification |
|---|---|
| Model | DH-280 |
| Rated Input Voltage (V) | AC 380V +/- 10% |
| Phase | Three-Phase |
| Frequency (Hz) | 50 / 60 |
| Rated Input Power (kVA) | 16.5 |
| Rated Output Current (A) | 280 |
| Output Current Range (A) | 50 – 280 |
| No-Load Voltage (V) | 8 – 12 |
| Rated Duty Cycle | 60% @ 280A (40degC) |
| Rebar Diameter Range (mm) | 10 – 25 |
| Welding Time per Joint (s) | 8 – 35 (diameter-dependent) |
| Clamping Force (kN) | 20 – 40 (via external fixture) |
| Upset Force (kN) | 15 – 30 (via external fixture) |
| Control Mode | Microprocessor with programmable phases |
| Weld Phases | Preheat / Flash / Upset Forge / Hold |
| Power Factor (cos phi) | 0.85 or above |
| Efficiency (%) | 85 or above |
| Insulation Class | F (155degC) |
| Protection Class (IP) | IP22S |
| Dimensions L x W x H (mm) | 580 x 360 x 520 |
| Net Weight (kg) | 35 |
| Output Connection | Copper bus bars / 70 mm2 cable lugs |
| Cooling Method | Forced Air (Fan Cooled) |
| Additional DC Applications | Electroplating rectifier, DC motor drive supply, lab power |
| Certification | CE (CSA, EAC available) |
Where the DH-280 Excels
High-Rise Building Construction
Butt welding of column and beam rebar cages from 16 to 25 mm diameter. Full-strength joints eliminate lap length congestion in heavily reinforced structural elements.
Bridge Deck Reinforcement
Continuous butt welding of bridge deck longitudinal rebar. Eliminates couplers and reduces steel waste compared to lapped splices on long-span bridge decks.
Precast Concrete Plants
Welding of rebar cages and mesh for precast beams, columns, and wall panels. Programmable weld parameters ensure repeatable joint quality across production batches.
Electroplating DC Supply
Reconfigurable as a regulated DC power supply for electroplating, anodising, and electrochemical processes. Constant-current mode with less than 1 % ripple for uniform coating deposition.
Laboratory & Test Power Supply
Serves as a high-current DC source for electrical testing, circuit breaker calibration, and transformer winding resistance measurement. Stable output with fine current resolution.
Dam & Water Treatment Plants
Welding of large-diameter rebar in mass concrete structures where joint integrity is critical. Proven performance on hydroelectric dam and wastewater treatment facility projects.
DH Series — Power Supply Comparison
| Parameter | DH-280 | DH-500 | DH-630 |
|---|---|---|---|
| Rated Current (A) | 280 | 500 | 630 |
| Input Power (kVA) | 16.5 | 28 | 36 |
| Rebar Dia. Range (mm) | 10 – 25 | 16 – 32 | 20 – 40 |
| Weld Time Range (s) | 8 – 35 | 12 – 50 | 15 – 65 |
| Duty Cycle | 60% @ 280A | 60% @ 500A | 60% @ 630A |
| Weight (kg) | 35 | 52 | 65 |
| Alternative DC Use | Yes | Yes | Yes |
| Best For | Mid-rise, precast, electroplating | High-rise, heavy columns | Bridges, dams, heavy construction |
Why Choose the DH-280
Programmable Multi-Phase Weld Control
Microprocessor-controlled welding sequencer with independently programmable preheat, flash, upset forge, and hold phases. Operators select the rebar diameter and grade on the front panel, and the controller automatically sets optimal current, time, and force parameters for each phase.
Dual-Purpose DC Power Supply
Beyond rebar butt welding, the DH-280 doubles as a general-purpose regulated DC power supply. Its low-ripple constant-current output (less than 1 %) makes it suitable for electroplating, anodising, battery charging, and laboratory testing applications where stable DC current is essential.
Full-Strength Joint Certification
When used with a suitable clamping fixture, the DH-280 produces butt-welded joints that meet or exceed the tensile strength of the parent rebar. This is verified through bend testing per ISO 17660-1 and tensile testing per ISO 15630-1, qualifying the joints for use in critical structural applications.
Site-Ready Construction
The 35 kg chassis features integrated lifting eyes and shock-absorbing rubber feet for operation on uneven construction site terrain. The IP22S-rated control panel is sealed against dripping water and construction dust, and the steel enclosure withstands the bumps and knocks of daily site handling.
Need Technical Advice? Talk to Our Welding Engineers
We will help you select the right model for your specific welding application and provide a detailed FOB quotation.
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