SRA250 Six-axis robotic arm (manipulator)
250kg / 2792mm
SRA250 Specifications
Nachi-Fujikoshi (NACHI) SRA250 spot welding robot, with a payload of 250kg and a reach of 2792mm.
Model introduction
SRA250: Rated load 250kg · Maximum reach: 2792mm · Repeatability± 0.2mm · Number of axles: 6 axes · Main body weight is 1030kg. Specifications are sourced from the official Nachi-Fujikoshi (NACHI) website.
SRA Series Spot Welding Robots · Series technical features
100-250kg · Automotive welding
Originating from the world's first servo motor spot welding robot in 1979.
SRA100J Short-arm high-speed design, SRA210/250 long arm covers large welding areas.
Wrist space supports welding machine cable packs, ensuring stable beats.
SRA Series Spot Welding Robots · Other models in the same series
Compare load and reach to choose the model that best suits your process.
SRA250 model positioning and working condition adaptation
SRA250 This is an industrial robot model belonging to the Nachi-Fujikoshi SRA series spot welding robots, with a rated load of 250kg, a motion radius of 2792mm, and a repeatability of ±0.2mm. Nachi-Fujikoshi's technical foundation is represented by Japanese compact models: the MZ series of low-load, high-speed models excel in lightweight arms and rhythmic beats; The control platform is the FD series controllers (FD8/FD11, etc.), and the program ecosystem is EX language + teach pendant.
From the perspective of working condition adaptation, the typical use for heavy-duty (250kg) positioning is:Vehicle body handling, large casting processing, building materials and heavy palletizing。 The extra-long reach (2792mm) is suitable for large workpieces and cross-line services, with attention to stiffness and vibration during large overhanging postures. ± 0.2mm repeatability meets handling and palletizing conditions; For precision assembly applications, it is recommended to use visual guidance for a closed-loop position. For heavy-duty models, the foundation is poured according to the manufacturer's drawings and settlement observation is conducted, with hoisting and maintenance space reserved during the layout phase.
| Parameters | Engineering interpretation and usage recommendations |
|---|---|
| Rated load capacity: 250kg | It is recommended to reserve a load margin of 20%–30%; Verification is made by combining end self-weight + workpiece + imbalanced load inertia, especially sensitive to high-speed conditions |
| Movement radius: 2792mm | Determine the radius of the workcell layout: bins, tooling, and fences are bounded by maximum arm span + safety distance; Verify the accessibility of each pick-and-place point during cross-station service |
| Repeatability: ±0.2mm | Repeatability ≠ absolute accuracy: Precision assembly requires external measurement closed-loop or visual guidance; Long-term accuracy trends rely on annual retest management |
| Number of axes: 6 | Six-axis all-posture capability, the preferred choice for complex trajectory and inclined surface operations |
| Main body weight: 1030kg | Installation base and foundation load-bearing check based on weight + dynamic load; Floor slab installation requires structural calculation, with heavy-duty models serving as independent foundations |
| Controller: FD series controllers (FD8/FD11, etc.) | Decide on the process ecosystem, spare parts channels, and second-hand residual value; Currently, spare parts channels are smooth, and repair and upgrade paths are mature |
Control systems and common failure modes
The SRA250 comes with FD series controllers (FD8/FD11, etc.), with EX language + teach pendant for its programming language and development environment. Maintenance of this generation of control platforms focuses on three basic components: power, storage, and cooling—most "sudden downtime" can be detected in advance when preventive maintenance is in place.
| Failure mode | Typical performance | Disposal recommendations |
|---|---|---|
| Driver alarm and power unit aging | Driver alarm and power unit aging | Included as a mandatory inspection item for annual maintenance, with spare parts stocked in advance |
| The encoder battery is depleted | Encoder battery depleted (origin lost) | Initial interpretation of alarm codes by reference with manuals, remote diagnosis allows for early positioning |
| Teach pendant cable core breakage | Teach pendant cable core breakage | Daily inspection coverage, with abnormal trends (abnormal noises/temperature rise/errors) recorded |
| Reducer lubrication deterioration | Reducer lubrication deterioration (temperature rise at high speeds) | Quarterly dust removal maintenance and cabinet temperature monitoring |
| Maintenance projects | Cycle recommendations | Key points |
|---|---|---|
| Battery Annual Replacement (Powered Operation) | Year | Battery Annual Replacement (Powered Operation) |
| High-speed model reducer grease is managed according to shortened cycles | According to the manufacturer's manual cycle | High-speed model reducer grease is managed according to shortened cycles |
| Quarterly inspection of control cabinet fans | Quarterly | Quarterly inspection of control cabinet fans |
| Cable and drag chain inspection | every six months | Insulation, shielding, and bending radius inspection of power and encoder lines, as well as wear of cables inside the drag chain, are the main causes of intermittent faults |
| Zero point and accuracy retest | Every year | Repeatability measured by dial gauges or laser trackers, drift trend digitization—accuracy degradation can be seen six months in advance |
| Control cabinet dust removal and fans | Every quarter | Filter cleaning, fan speed and noise checks, cabinet temperature recording; Dust environments shorten the cycle |
Henghuan's service capabilities for SRA250
This site is a third-party robotics technology service provider. The SRA250 supports eight major business services (listed by service frequency for each model):
- Maintenance and repair: For SRA250 on-site diagnostics, board-level repairs, and annual maintenance contracts—we will follow SOPs for annual battery replacement (live operation) and other brand-exclusive items, with same-day response from Sichuan and Chongqing.
- Used & in-stock robot sales: The MZ series has stable second-hand circulation, offering high speed sorting and cost-effective loading and unloading conditions, making it a cost-effective Japanese choice. Models in the SRA250 or equivalent class come with a full-function test report and a 12-month warranty.
- Sales of new industrial robots: When adding new production lines or replacing entire batches, we conduct cross-brand selection comparisons based on process requirements (including Nachi-Fujikoshi models of the same class) and provide configuration and pricing plans.
- Applied technology services: Process programming, trajectory optimization, tap time potential, and model change formula management for SRA250, with targeted tuning for vehicle body handling, large casting handling, building materials, and heavy-duty palletizing conditions.
- Research and development of automation equipment: Custom fixture ends, peripheral tooling, and safety fences for SRA250, with interfaces designed according to Chifujietsu flange and IO standards.
- Robot rental: For short-term production capacity or process validation periods, SRA250 equivalent in-stock models can be rented, including transportation, installation, and commissioning; flexible lease periods allow for repurchasing.
Common issues with this device
Is it easy to find SRA250 spare parts?
Nachi-Fujikoshi: Spare parts channels for this generation are smooth; we have in-stock or short-cycle channels for regular parts such as drivers, power modules, batteries, and teach pendant components; It is recommended to allocate consumables for annual battery replacement (live operation) according to the annual maintenance contract.
With a nominal load of 250kg, how much can it actually handle?
The rated load is the static load limit of the flange surface. In actual selection, three factors must be considered: the self-weight of the end fixture (vacuum suction cup groups or grippers often account for 2–5kg), the inertia generated by the workpiece offload (checked according to the inertia ratio when the center of gravity deviates from the flange center), and the dynamic load during high-speed movement. The conventional engineering practice is to keep the "end + workpiece" within 70%–80% of the rated value to ensure cycle time and service life.
If the equipment's accuracy deteriorates after several years of use, how can it be restored?
According to the inspection order: first check whether the zero point is drifting (common after collision or battery depletion), then perform zero calibration; Check the reducer's return error (actual measurement of forward and reverse positioning deviation; if exceeded, disassemble or replace); Then check the installation base fastening and foundation settlement; Finally, trajectory compensation parameter restructuring. Most accuracy issues can be mostly restored after calibration and maintenance, so there is no need to rush into major repairs—we first release the inspection data before deciding on the plan.
Is the used SRA250 worth buying?
The MZ series is a Japanese choice for stable second-hand circulation, offering high speed sorting and cost-effective loading and unloading conditions. Three essential items for second-hand procurement: comprehensive inspection reports (axial accuracy, driver status, insulation and battery), maintenance history and operating hours, controller generation, and software license integrity. Every used machine we sell comes with inspection records and a 12-month warranty, and we can also accept third-party inspections designated by customers.
Need technical support or procurement for this model?
Whether it's model selection comparison, installation and commissioning, or maintenance of in-use equipment, you can contact Henghuan. Tell us about your processes, loads, and equipment status, and we will provide third-party technical support and solution recommendations.
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