Automatic Girth Welders
At Key Plant Automation, we specialize in advanced welding automation designed to meet the high demands of modern industry. Our Automatic Girth Welders (AGWs)—also known as girth welders, tank welders, or the “3 o’clock welder”—are trusted around the world to dramatically improve storage tank fabrication speed, consistency, and safety.
Whether you’re fabricating oil storage tanks in Texas, building water treatment vessels in California, or working in nuclear and petrochemical facilities across the U.S., our AGW solutions are engineered to help you work faster, smarter, and safer.
Why Choose Key Plant AGW Tank Welders?
Cut Fabrication Time by 40%
We know that project timelines are tighter than ever, and every hour saved on the job site counts. That’s why our Automatic Girth Welders are engineered to dramatically reduce welding cycle times—cutting fabrication time by up to 40% compared to traditional manual methods. This isn’t just a performance boost; it’s a game-changer for your bottom line.
From massive fuel storage tanks and municipal water towers to chemical processing vessels, our AGWs enable you to complete more welds in less time, reduce bottlenecks, and keep projects on schedule. By automating the girth welding process, you not only increase productivity but also reduce dependency on manual labor—lowering costs while delivering consistent, high-quality results every time.
Built-In Engineering Excellence
Every Key Plant AGW is the result of decades of engineering expertise. With both Single-Sided, Double-Sided, and Mini AGW options available, our systems are ready for tanks of all sizes and applications.
Operator Centric Design
Ergonomics and operator comfort are built into every machine. Reduce fatigue, increase uptime, and boost jobsite morale with a system that’s designed for real-world working conditions.
Versatility Across Industries
From oil & gas to renewables, chemical processing, and wastewater treatment, our AGWs are used globally in sectors that demand uncompromising performance. They’re suitable for carbon steel, stainless steel, and specialty alloys.
Enclosed Operator Cabins (Optional)
Safety is non-negotiable. Optional operator cabins provide a protected working environment—especially important on windy, dusty, or extreme temperature sites.
Automatic Girth Welder Models Available
We offer built-to-spec Automatic Girth Welders to suit every tank fabrication requirement—whether you’re tackling large-scale industrial projects or working within tight spaces. Each AGW is designed with productivity, precision, and versatility in mind.
Single-Sided AGW
Our Single-Sided Automatic Girth Welders are engineered for efficiency, accuracy, and ease of use—ideal for tank fabrication projects where welding from one side is preferred or required. Designed to travel around the circumference of vertical storage tanks, these units deliver high-quality welds with minimal setup and operator intervention.
Perfect for mid-size to large tank projects, the single-sided AGW offers a practical solution when access to both sides of the weld joint is limited. With smooth travel, stable arc control, and intuitive operator controls, it ensures fast, repeatable welds that meet demanding quality standards in industries such as oil & gas, water treatment, chemical processing, and power generation.
Key Features
- One-Sided Welding Capability – Weld the entire girth seam from a single side, ideal for applications with restricted access.
- Adjustable Travel Speed & Torch Positioning – Fine-tune weld parameters for precise control and optimal results.
- Robust Construction – Built to withstand tough jobsite conditions with a durable, heavy-duty frame.
- Quick Setup & Deployment – Minimize downtime with a fast assembly process and easy-to-use interface.
- Operator Control Console – Ergonomic controls for seamless operation and real-time weld adjustments.
- Compatible with Multiple Welding Processes – Suitable for SAW (Submerged Arc Welding), FCAW, or custom configurations.
- Optional Safety Enclosures – Add an operator cabin for improved safety and comfort on-site.
Looking to improve productivity on your next tank build? Our Single-Sided AGWs are the reliable, high-performance solution trusted by fabricators worldwide.
Double-Sided AGW
When time is critical and efficiency is non-negotiable, our Double-Sided Automatic Girth Welders (AGWs) are the ultimate solution. Engineered to weld both the inner and outer sides of a tank seam simultaneously, these high-performance systems double your output without doubling your effort—making them the go-to choice for large-scale, high-volume tank fabrication projects.
Ideal for industries such as oil & gas, power generation, petrochemical, and bulk liquid storage, our double-sided AGWs significantly reduce welding cycle times, improve weld penetration, and ensure uniformity on both sides of the seam. Whether working on-site or in a fabrication yard, they deliver unmatched speed, consistency, and quality—all while reducing labor requirements.
Key Features
- Simultaneous Inside & Outside Welding – Boost productivity by completing both sides of the girth weld in a single pass.
- High-Speed Travel System – Designed for continuous operation with adjustable speed controls to match project requirements.
- Independent Torch Adjustment – Fine-tune each torch separately for precise alignment and consistent weld integrity.
- Heavy-Duty Frame Construction – Built to withstand rugged environments and heavy industrial use.
- Integrated Control System – Centralized operator panel for easy monitoring and adjustments during operation.
- Compatible with SAW & FCAW Processes – Flexible design to support various welding configurations and materials.
- Rapid Setup & Mobility – Quick deployment with minimal disruption to your workflow.
- Optional Operator Cabin – Enclosed workstation available for enhanced safety and comfort in harsh conditions.
If your goal is to reduce turnaround times and elevate weld quality, the Key Plant Double-Sided AGW is the high-performance machine you can depend on. Rugged, reliable, and built to work—project after project.
Double-Sided AGW
When time is critical and efficiency is non-negotiable, our Double-Sided Automatic Girth Welders (AGWs) are the ultimate solution. Engineered to weld both the inner and outer sides of a tank seam simultaneously, these high-performance systems double your output without doubling your effort—making them the go-to choice for large-scale, high-volume tank fabrication projects.
Ideal for industries such as oil & gas, power generation, petrochemical, and bulk liquid storage, our double-sided AGWs significantly reduce welding cycle times, improve weld penetration, and ensure uniformity on both sides of the seam. Whether working on-site or in a fabrication yard, they deliver unmatched speed, consistency, and quality—all while reducing labor requirements.
Key Features
- Simultaneous Inside & Outside Welding – Boost productivity by completing both sides of the girth weld in a single pass.
- High-Speed Travel System – Designed for continuous operation with adjustable speed controls to match project requirements.
- Independent Torch Adjustment – Fine-tune each torch separately for precise alignment and consistent weld integrity.
- Heavy-Duty Frame Construction – Built to withstand rugged environments and heavy industrial use.
- Integrated Control System – Centralized operator panel for easy monitoring and adjustments during operation.
- Compatible with SAW & FCAW Processes – Flexible design to support various welding configurations and materials.
- Rapid Setup & Mobility – Quick deployment with minimal disruption to your workflow.
- Optional Operator Cabin – Enclosed workstation available for enhanced safety and comfort in harsh conditions.
If your goal is to reduce turnaround times and elevate weld quality, the Key Plant Double-Sided AGW is the high-performance machine you can depend on. Rugged, reliable, and built to work—project after project.
Complete AGW Tank Welder Packages – Ready to Work
Every Key Plant AGW is shipped fully equipped for immediate deployment, including:
Advanced Welding Systems
High-performance SAW (Submerged Arc Welding) or FCAW-ready welding heads with precise heat input control for consistent, high-quality welds.
Flux Delivery, Recovery & Transfer Systems
Integrated flux handling systems ensure continuous operation, reduce waste, and keep your welds clean and contaminant-free.
All Necessary Controls & Cabling
Fully wired with pre-installed control panels, cables, and connectors—engineered for quick setup and seamless integration with your existing infrastructure.
Operator Platform or Cabin (Optional)
Ergonomic operator stations or enclosed cabins provide enhanced comfort and protection—ideal for long shifts or harsh weather conditions.
Tailored Solutions for Thin-Wall Tanks
Not all tanks are built the same. Thin-walled storage tanks demand a delicate balance of heat input and control. Our specially developed AGW systems offer low-distortion welding to preserve structural integrity and extend tank lifespan.
GLOBAL REACH. PROVEN PERFORMANCE.
Direct from the Manufacturer – Trusted Worldwide
As the original equipment manufacturer (OEM), Key Plant Automation offers full in-house design, production, and support for all our AGW systems. That means lower costs, faster lead times, and unmatched quality control—with dedicated customer service to match.
Frequently Asked Questions (FAQ)
What is an automatic girth welder?
An automatic girth welder (AGW) is a specialized welding machine designed to automate the welding of horizontal or circumferential seams—known as girth welds—on large cylindrical structures like storage tanks and pressure vessels. Commonly referred to as a “3 o’clock welder”, the AGW travels around the circumference of the tank, delivering consistent, high-quality welds with minimal operator input. These machines are engineered for speed, precision, and reliability in heavy-duty industrial environments.
What is automatic girth welder used for?
Automatic girth welders are primarily used in the fabrication of large-diameter storage tanks and vessels. They are ideal for welding carbon steel, stainless steel, and alloy tanks in vertical or horizontal orientations. Typical applications include fuel and oil tanks, water towers, chemical vessels, silos, and LNG/LPG storage units. By automating the girth weld process, these machines significantly reduce manual labor, increase welding speed, and ensure repeatable, high-quality results.
What are the benefits of investing in automatic girth welder?
Investing in an AGW system offers numerous advantages for fabrication shops and contractors, including:
- Up to 40% reduction in welding time compared to manual methods
- Consistent, high-quality welds with improved fusion and bead appearance
- Lower labor costs through reduced manual input and faster job completion
- Enhanced operator safety and comfort, especially with optional enclosed cabins
- Minimized rework and weld defects, thanks to precise travel and arc control
These benefits translate to higher productivity, reduced costs, and improved project timelines, making AGWs a smart long-term investment for tank fabrication.
Which industries use an automatic girth welder?
Automatic girth welders are used across a wide range of heavy industries where large storage tanks or vessels are essential. These include:
- Oil & Gas – crude storage, refineries, LNG/LPG tanks
- Water & Wastewater Treatment – potable water tanks, clarifiers
- Chemical & Petrochemical – process vessels and chemical storage
- Power Generation – cooling water tanks, nuclear containment
- Renewables – biofuel and energy storage applications
- Food & Beverage – sanitary tanks and fermentation vessels
Any industry that relies on cylindrical tank structures can benefit from the efficiency and precision of an AGW system.
Can my automatic girth welder be customized?
Yes, absolutely. At Key Plant Automation, we offer customized AGW solutions to meet the specific requirements of your operation. Whether you need:
- Single-sided or double-sided welding configurations
- Specialized setups for thin-walled tanks
- Adjustable track systems for varying tank diameters
- Integration with specific welding processes (SAW, FCAW, etc.)
- Optional operator cabins or custom control panels
Our in-house engineering team will work with you to build a system that’s tailored to your production environment, safety needs, and performance goals.
Why Choose Key Plant?
- Engineered & Manufactured In-House in the UK – Every system is proudly designed and built at our UK headquarters to ensure full control over quality, performance, and reliability.
- Supported Across North America – Our dedicated Key Plant USA team ensures fast, responsive service, technical support, and streamlined delivery across the United States.
- Custom solutions – Need something specific? Our in-house design and control systems teams work with you to build exactly what your operation demands.
- Trusted by industry leaders from training and installation to ongoing technical support, we’re committed to your success long after delivery.
Let’s Get You Set Up
Need a reliable automatic girth welder? Contact Key Plant USA today to discuss your operation requirements. We’ll help you build a system tailored to your application, timeline, and budget.
📞 Call now +1 832 770 9173 or request a quote online — and take your welding productivity to the next level with automated solutions that work as hard as you do.
Looking to Rent a Welding Automation Option Instead?
If you’re not looking to purchase, we offer a wide selection of welding automation systems available for short-term or long-term rental
Whether you’re ready to invest or upgrade your existing setup, we’ll help you find the right fit.
Still Exploring Your Welding Automation Options?
Not sure if a automatic girth welder is the right solution for your operation?
Considering a side beam system, welding manipulator, or another type of automated welding setup?
We design, manufacture and supply a wide range of weld automation, handling and positioning solutions—ready when you are.