SIASUN SR220A-125/3.10 (SR220A-125/3.10)

On a welding line, the wrist is where a robot earns or loses its keep. The arm can be long and the base can be massive, yet if the joints nearest the tool struggle to control a heavy gun swinging into position, every cycle surrenders a fraction of a second to settling, and those fractions accumulate across a shift. The SIASUN SR220A-125/3.10 tackles the problem from the tool end. A custom high-inertia motor strengthens wrist torque, a backlash-free gearbox structure stiffens the machine, and motion planning is tuned to move briskly without unsettling the load. The outcome is a long-reach, heavy-payload arm conceived for cells in which speed and steadiness must coexist rather than compete.

Robots Middle East sells the SIASUN SR220A-125/3.10 to manufacturers, system integrators and engineering contractors throughout the Middle East. Our team prepares each quotation around the intended application, checks the configuration against the manufacturer's datasheet, and coordinates delivery to your site together with the technical support that continues after commissioning.

Background

SIASUN and its industrial robot range

SIASUN is a Chinese automation company whose activities span industrial robots, mobile robots and complete automation systems. Its articulated industrial robots are organised into families by payload class, and the SR220A-125/3.10 sits within the large-payload group, where each model represents a particular balance between the weight it carries and the distance it can cover. That structure is useful to a production engineer: rather than adapting a cell to whatever arm happens to be available, the engineer can select the model whose envelope suits the fixtures, the tooling and the floor space already planned.

Within that family, the SR220A-125/3.10 leans towards reach. It is the arm to consider when parts are large, fixtures are spread out, or one robot must serve several stations from a single position.

A wrist-first design philosophy

Three engineering decisions define this model. The first is the gearbox. SIASUN describes a forward-designed, all-new 220 five-axis backlash-free gearbox structure, and attributes to it an increase in overall machine rigidity. Backlash, the small free play between gear teeth, is precisely what allows a heavy tool to drift or oscillate when the arm stops, so removing it addresses accuracy and settling at the same time.

The second is the wrist drive. A custom high-inertia motor from SIASUN's own brand raises the allowable end-effector inertia, which matters whenever the tool is not only heavy but also bulky or offset from the flange, as welding guns and large grippers often are.

The third is software. Optimised dynamic algorithms, NURBS transitions between path segments and variable-speed, variable-acceleration planning are intended to keep motion smooth while shortening the time between points. Taken together, these choices treat the robot as a system in which mechanics and control are designed to support each other.

Technical Specifications

Specifications are as published by the manufacturer and are confirmed against the datasheet at quotation.

The manufacturer has not published the weight, the axis speeds, the axis motion ranges, the power supply, the controller model, the mounting options, the operating temperature or the scope of delivery; Robots Middle East confirms each of these with your quotation.

How does the SR220A-125/3.10 shorten spot welding cycles?

Spot welding is a sequence of short, heavy moves: the gun travels to a point, clamps, welds, releases and moves on, often dozens of times per part. Most of the cycle is therefore spent accelerating, decelerating and waiting for the tool to settle, rather than welding. SIASUN states that NURBS transitions combined with variable-speed, variable-acceleration motion planning improve spot welding cycle time by over 11%.

The mechanics support that gain. A stiffer structure, with overall rigidity improved by over 17%, means less deflection when the arm brakes, so the gun reaches a stable position sooner. The backlash-free gearbox removes play that would otherwise let the tool rock at each stop. The high-inertia wrist motor, with an allowable end-effector inertia raised by 8%, gives the controller the torque to swing a heavy gun decisively. With a repeatability of ±0.06mm, each weld point can be revisited consistently across thousands of cycles. For a body shop, the practical value is that time saved per point multiplies across every point, every part and every shift.

What do the IP54 and IP67 ratings mean for a working cell?

Protection ratings describe how well a machine resists the ingress of dust and water. The SR220A-125/3.10 carries IP54 for the whole machine and IP67 for the wrist, achieved in part through a customised aviation plug sealed cover. In general terms, an IP54 rating indicates protection against harmful dust deposits and splashing water, while IP67 at the wrist denotes a dust-tight enclosure that also withstands temporary immersion.

The distinction is sensible. The wrist sits closest to the process, where weld spatter, coolant, cleaning fluids and fine particulate are most concentrated, so it receives the higher rating. For facilities in the region, where airborne dust can reach production halls and washdown routines are common, that sealing deserves attention during cell planning, and Robots Middle East will review it against your site conditions when preparing the quotation.

Who is the SIASUN SR220A-125/3.10 for?

The most natural buyers are automotive body shops and their tier suppliers, where spot welding cycles dominate line time and a shorter cycle translates directly into throughput. Fabricators handling large steel or aluminium assemblies form a second group, since the long reach allows one arm to cover generous fixtures or serve more than one station.

System integrators building turnkey cells for heavy tooling will find the combination of payload, reach and wrist inertia useful when end effectors are bulky or offset. Plants operating in dusty or wet environments, including those using washdown, should weigh the sealed wrist and protected machine body in their selection.

Where a project calls for a different balance of capacity and reach, Robots Middle East can compare this arm with neighbouring models such as the SIASUN SR220A-220/2.66 (SR220A-220/2.66) or the SIASUN SR270A-220/3.21 (SR270A-220/3.21), each of which is described on its own page. The wider family is presented under Large Payload, and the complete range under Industrial Robots.

What is the SIASUN SR220A-125/3.10 used for?

1. Spot welding: carrying heavy welding guns through dense point sequences on body-in-white lines.
2. Large-part handling: transferring sizeable panels and assemblies between fixtures, conveyors and stations.
3. Machine tending: loading and unloading presses or machining centres that sit some distance from the robot base.
4. Fixture loading: placing components into welding or assembly jigs with consistent positioning.
5. Heavy assembly: presenting bulky components for joining, fastening or inspection.
6. Harsh-environment cells: operating where dust, spatter or cleaning fluids demand a well-sealed wrist.

Pricing and Availability

Robots Middle East supplies the SIASUN SR220A-125/3.10 on a quotation basis, so that the configuration, tooling interface and cell requirements are agreed before any commitment. Please share your application, the parts to be handled and your site details, and our team will respond with a tailored proposal. Delivery, customs clearance and technical support are arranged together with the quotation. To begin, use the quotation request available on this page.

Frequently Asked Questions

What payload does the SIASUN SR220A-125/3.10 handle?

It has a payload of 125 kg (275.6 lbs). The final suitability of any tool also depends on its inertia and offset, which Robots Middle East reviews with you at quotation.

How far can the SR220A-125/3.10 reach?

The reach is 3100mm, making it suited to large fixtures and cells in which one robot serves several positions.

How repeatable is it?

Repeatability is ±0.06mm, which supports consistent weld point placement and part positioning over long production runs.

Is the robot protected against dust and water?

Yes. The whole machine is rated IP54 and the wrist IP67, aided by a customised aviation plug sealed cover.

What makes the gearbox notable?

It uses a forward-designed, all-new 220 five-axis backlash-free gearbox structure, which SIASUN credits with increasing overall machine rigidity by 17%.

Which controller and mounting options are available?

The controller model and mounting options have not been published. Robots Middle East confirms both, together with weight and power supply, when preparing your quotation.

Where can I buy the SIASUN SR220A-125/3.10 and what does it cost?

You can buy it from Robots Middle East, which supplies it across the Middle East. Pricing depends on configuration and project scope, so it is provided in a tailored quotation requested from this page.

Summary

The SIASUN SR220A-125/3.10 is designed on the premise that a heavy, long-reach robot is only as productive as its wrist and its stops. A stiffer backlash-free gearbox, a high-inertia wrist motor and smoother motion planning work together so that a substantial tool can travel quickly and settle promptly, which is why SIASUN can point to a measurable gain in spot welding cycle time. Add a sealed wrist, a protected machine body and fine repeatability, and the arm becomes a strong candidate for welding and heavy handling cells across the region. For a configuration confirmed against the datasheet and a quotation prepared by Robots Middle East, this page is the starting point.