Welding Services at METCO

Modern manufacturing depends on reliable welding, consistent quality, and efficient production. METCO supports OEMs with welding, fabrication, machining, finishing, and assembly services from a single facility. As a result, customers simplify their supply chains and streamline project management.

MIG, TIG, and Production Welding

METCO uses multiple welding processes to match application requirements. MIG welding delivers high productivity and cost efficiency for production work. TIG welding provides exceptional control for precision assemblies and appearance-critical components. Furthermore, our welding process selection considers material type, joint geometry, production volume, cosmetic requirements, and performance expectations.

Sheet Metal Fabrication and Welding

Many OEM products begin as sheet metal components. Therefore, METCO combines laser cutting, CNC forming, and welding to create complete assemblies. This approach produces electrical enclosures, equipment covers, machine guards, control cabinets, and production components. Moreover, formed sheet metal designs improve stiffness while reducing material consumption.

Structural and Equipment Weldments

The company manufactures welded structures that support demanding industrial applications. These assemblies include machine frames, equipment bases, conveyor structures, support systems, and OEM production weldments. Furthermore, successful structural fabrication requires attention to strength, dimensional control, weld quality, and manufacturability. Consequently, engineers achieve reliable performance without unnecessary manufacturing cost.

Machined Weldments

Some assemblies require both structural strength and precision features. In response, METCO produces machined weldments that combine fabrication and CNC machining. Welding creates the primary structure, while machining refines critical interfaces. As a result, customers obtain accurate mounting surfaces, precision hole locations, bearing bores, and alignment features without machining entire components from solid material.

OEM Manufacturing Support

OEM manufacturers face constant pressure to reduce costs, improve quality, and maintain reliable delivery schedules. Therefore, METCO works closely with engineering and purchasing teams throughout the project lifecycle. Early collaboration helps identify manufacturability improvements, reduce fabrication complexity, and eliminate unnecessary cost. Additionally, strong communication supports accurate quotations, smoother production, and predictable outcomes

Chattanooga Manufacturing Capabilities

METCO serves OEM manufacturers from Chattanooga, Tennessee. The company supports regional and national customers with fabrication, welding, machining, finishing, and assembly services. Furthermore, the facility combines manufacturing expertise with integrated production capabilities. As a result, customers receive complete welded assemblies from a single manufacturing partner.

Learn more about Welding:

MIG Welding

TIG Welding

Weld Distortion

Weld Inspection

Welding Material Selection

1. Introduction to Industrial Welding

What Is Industrial Welding?

Industrial welding permanently joins metal components through fusion. Manufacturers use welding to create strong and reliable assemblies. Moreover, welding allows engineers to build large structures from individual components. This approach often reduces material waste and manufacturing costs. Consequently, welding supports products that would be expensive to machine from solid material.

Industrial welding serves many industries. For example, manufacturers use welded assemblies in machinery, transportation equipment, material handling systems, automation equipment, and industrial infrastructure. As a result, welding remains one of the most important manufacturing processes in modern industry.

How Welding Fits Into OEM Supply Chains

Many OEM products depend on welded assemblies. Machine frames, equipment enclosures, support structures, skids, battery enclosures, and conveyor systems frequently use welded construction. Therefore, welding often serves as a critical step within the manufacturing process.

OEM manufacturers rarely evaluate welding alone. Instead, they evaluate complete manufacturing capability. As a result, suppliers often combine welding with laser cutting, forming, machining, finishing, and assembly services. This approach reduces supplier complexity and improves project coordination. Furthermore, integrated suppliers help simplify procurement activities and production scheduling.

Successful supply chains also depend on communication. Consequently, engineers, buyers, and fabricators must clearly define materials, weld requirements, tolerances, inspection needs, and delivery expectations. Strong collaboration helps reduce risk, improve quality, and support reliable production outcomes.

Understanding Fabricated Weldments

A fabricated weldment is an assembly of components joined through welding. Manufacturers typically create weldments from plate, tubing, sheet metal, structural shapes, or machined parts. Furthermore, many welded designs include secondary operations such as machining, finishing, and assembly.

Fabricated weldments appear throughout modern industry. Common examples include machine bases, equipment frames, conveyor assemblies, structural supports, automation systems, transportation equipment, and industrial skids. As a result, weldments form the foundation of countless manufactured products.

Engineers often choose this method of design because they balance structural performance with manufacturing efficiency. Instead of machining large components from solid stock, manufacturers fabricate structures from smaller pieces and machine only critical features. Therefore, welding frequently deliver the best combination of strength, precision, and cost control.

Successful metal joining requires more than strong welds. Designers must consider joint design, material selection, distortion control, dimensional accuracy, inspection requirements, manufacturability, and service conditions. When these factors work together, welded assemblies deliver reliable performance throughout their operating life.

2. Types of Fabricated Weldments and Industrial Applications

Structural Welding

Structural weldments support loads and resist mechanical forces. Manufacturers commonly build these assemblies from plate, tubing, channel, angle, and structural shapes. As a result, structurally joined metal components appear throughout industrial facilities and equipment.

Common applications include equipment supports, conveyor structures, platforms, catwalks, mezzanines, and machinery frames. Furthermore, engineers value structural steel because they provide an efficient balance of strength, stiffness, and material utilization.

Successful structural designs require more than strong welds. Designers must also consider load paths, manufacturability, inspection requirements, and lifecycle performance. Consequently, good design improves both reliability and cost efficiency.

Machine Bases and Equipment Frames

Machine bases and equipment frames form the backbone of industrial equipment. These structures support motors, tooling, automation systems, actuators, and production machinery. Therefore, dimensional stability becomes critical to long-term performance.

Engineers rarely machine these large structures from solid stock. Instead, they fabricate them from plate and tubing and machine only critical interfaces afterward. As a result, manufacturers reduce material consumption while maintaining precision where it matters most.

Common examples include CNC machine bases, robotic cells, packaging equipment, process skids, and automation platforms. Moreover, these structures often combine fabrication and machining into a single manufacturing strategy.

Precision Machined Weldments

Welded fabrication with precision machining follows a flow: First, manufacturers assemble and weld the structure. Next, they machine critical surfaces and features to final dimensions. This approach balances structural efficiency with dimensional accuracy.

Typical machined features include mounting surfaces, bearing bores, precision holes, alignment pads, and interface locations. Consequently, precision machined weldments support applications that require both strength and precision.

Industries frequently use machined weldments in heavy machinery, automation equipment, material handling systems, energy equipment, and transportation products. Furthermore, this method often costs less than machining an entire assembly from solid material.

Sheet Metal Weldments

Sheet metal weldments begin with laser-cut and formed sheet metal components. Fabricators then assemble these components through welding. As a result, manufacturers can create lightweight and highly repeatable products.

Common examples include electrical enclosures, machine guards, battery enclosures, equipment covers, access panels, and control cabinets. Additionally, formed bends increase stiffness without adding excessive weight

Sheet metal weldments often provide excellent strength-to-weight performance. Therefore, engineers frequently select them when material efficiency and production scalability matter

Tubular Weldments

Tubular weldments use round, square, or rectangular tube as the primary structural element. These hollow sections provide excellent stiffness while minimizing weight. Consequently, tubular designs remain popular across many industries.

Manufacturers use tubular weldments for vehicle frames, equipment chassis, safety guarding, carts, racks, agricultural equipment, and material handling systems. Furthermore, tubular structures often simplify fabrication compared to alternative designs.

When weight reduction becomes a priority, tubular weldments often provide an attractive solution. Therefore, engineers frequently choose tubular construction to maximize structural efficiency

Heavy Plate Weldments

Heavy plate weldments use thicker steel plate sections to support demanding service conditions. These assemblies commonly operate in applications that require high load capacity and long-term durability

Typical examples include mining equipment, construction machinery, crane components, industrial presses, heavy equipment frames, and power generation systems. In addition, many heavy plate weldments require advanced fixturing, distortion control, and post-weld machining.

Engineers must pay close attention to heat input, residual stress, distortion, and weld sequencing. Consequently, successful fabrication requires both welding expertise and strong manufacturing controls

OEM Production Assemblies

Many OEMs purchase complete welded assemblies instead of individual components. These assemblies often combine cutting, forming, welding, machining, hardware installation, finishing, and final assembly operations. As a result, customers receive production-ready products from a single supplier.

Examples include agricultural equipment modules, transportation assemblies, automation systems, generator skids, and material handling equipment. Furthermore, integrated manufacturing reduces supplier complexity and improves project coordination.

OEM production assemblies help manufacturers focus on product development and customer support. Meanwhile, fabrication partners manage production activities and manufacturing execution

3. Welding Processes Explained

MIG (GMAW) Welding

Gas Metal Arc Welding, commonly called MIG welding, is the most widely used welding process in modern fabrication. The process uses a continuously fed wire electrode, shielding gas, and an electric arc to join metal components. As a result, manufacturers achieve high productivity and consistent weld quality.

Many fabrication shops rely on MIG welding for daily production. For example, manufacturers use it for machine frames, equipment enclosures, conveyor components, agricultural equipment, and OEM production assemblies. Furthermore, MIG welding adapts well to both manual and automated operations.

MIG welding offers several advantages. First, the process delivers high deposition rates. Next, operators can learn the process relatively quickly. In addition, MIG welding supports robotic automation and repeatable production. Consequently, manufacturers often achieve lower labor costs and faster throughput.

However, no process fits every application. MIG welding typically produces more spatter than TIG welding. Additionally, outdoor conditions can affect shielding gas performance. Nevertheless, MIG welding remains the preferred choice for many industrial fabrication projects because it balances quality, speed, and cost.

TIG (GTAW) Welding

Gas Tungsten Arc Welding, commonly called TIG welding, prioritizes precision and weld appearance. The process uses a non-consumable tungsten electrode to create the arc. Meanwhile, the welder adds filler metal separately when required. As a result, TIG welding provides exceptional control over the weld puddle.

Manufacturers frequently select TIG welding for stainless steel and aluminum applications. Common examples include food processing equipment, medical equipment, pharmaceutical systems, aerospace components, and cosmetic weldments. Therefore, engineers often specify TIG welding when appearance and precision remain important.

TIG welding creates clean and visually attractive welds. Furthermore, the process generates minimal spatter and excellent weld control. Consequently, manufacturers often reduce finishing requirements after welding.

The process requires greater operator skill than MIG welding. Additionally, TIG welding runs at slower travel speeds and lower deposition rates. Therefore, labor costs often exceed those of MIG welding. Even so, manufacturers continue to choose TIG welding when weld quality and appearance outweigh maximum production speed.

Resistance Spot Welding

Resistance spot welding joins overlapping metal sheets through electrical resistance and applied pressure. Unlike MIG and TIG welding, the process generally does not require filler metal. Instead, heat forms within the contact area and creates a welded nugget between the materials.

Manufacturers use resistance spot welding extensively in sheet metal production. Common applications include electrical enclosures, appliance panels, automotive components, battery housings, and electronic products. Consequently, the process plays a major role in high-volume manufacturing environments.

One of the greatest advantages of spot welding is speed. The process creates welds in very short cycle times. Additionally, manufacturers can automate spot welding easily. As a result, production lines achieve high throughput and excellent repeatability.

However, spot welding works best with overlapping joints and relatively thin materials. Therefore, designers must account for those limitations during product development. When the application fits the process, resistance spot welding provides an efficient and economical joining solution.

Induction Welding

Induction welding uses electromagnetic energy to heat metal at the joint location. The process generates heat without direct contact between the induction coil and the work-piece. As a result, manufacturers achieve localized and controlled heating.

Manufacturers commonly use induction welding in tube and pipe production. The process also supports applications that require continuous and highly repeatable welds. Furthermore, induction systems often operate at high production speeds. Therefore, manufacturers can support demanding production volumes efficiently.

Induction welding concentrates heat near the joint area. Consequently, surrounding material experiences less thermal exposure than many conventional welding methods. This characteristic can reduce distortion and improve dimensional consistency.

Engineers typically select induction welding for specialized applications rather than general fabrication. Nevertheless, the process remains an important manufacturing technology where speed, consistency, and continuous production drive equipment selection.

4. Weldment Materials Guide

Material selection influences weldability, strength, corrosion resistance, weight, fabrication cost, and long-term performance. Therefore, engineers should evaluate the entire application before selecting a material. The best material is not always the strongest or least expensive option. Instead, the best material delivers the required performance at the lowest lifecycle cost

Carbon Steel Weldments

Carbon steel remains the most commonly used weldment material in industrial manufacturing. Manufacturers choose carbon steel because it offers excellent weldability, broad availability, and low material cost. As a result, carbon steel serves as the default material for many fabricated assemblies.

Common grades include A36, A572, A1011, HRPO steel, and low-alloy structural steels. These materials provide predictable fabrication characteristics and strong structural performance. Furthermore, most shops can cut, form, weld, and machine carbon steel efficiently

Typical applications include:

• Machine frames
• Equipment bases
• Conveyor systems
• Structural supports
• Agricultural equipment
• Material handling equipment
• Industrial skids

Carbon steel works well when cost control remains the primary objective. However, engineers usually add paint, powder coating, or other protective finishes because carbon steel can corrode in exposed environments

Carbon Steel Advantages and Limitations

Advantages	Limitations
Low material cost	Requires corrosion protection
Excellent weldability	Higher weight than aluminum
Easy to machine	Ongoing coating maintenance
Widely available	Limited natural corrosion resistance
High stiffness	Less suitable for weight-sensitive designs

Stainless Steel Weldments

Stainless steel provides outstanding corrosion resistance and long-term durability. Unlike carbon steel, stainless steel develops a protective chromium-rich surface layer that helps resist corrosion. Consequently, many manufacturers use stainless steel in harsh or sanitary environments.

Common grades include 304, 304L, 316, and 316L stainless steel. Among these options, 304 stainless steel remains the most widely specified grade because it balances corrosion resistance, weldability, and cost. Meanwhile, 316 stainless steel performs better in aggressive chemical and marine environments.

Typical applications include:

• Food processing equipment
• Pharmaceutical systems
• Medical equipment
• Commercial kitchens
• Water treatment equipment
• Chemical processing systems
• Washdown environments

Furthermore, stainless steel often eliminates the need for painting or coating. As a result, manufacturers can reduce maintenance requirements throughout the product lifecycle.

Stainless Steel Advantages and Limitations

Advantages	Limitations
Excellent corrosion resistance	Higher material cost
Attractive appearance	More difficult forming
Long service life	Greater distortion potential
Suitable for sanitary applications	Increased fabrication cost
Good mechanical properties	More process-sensitive welding

Aluminum Weldments

Aluminum offers significant weight savings compared to steel. In fact, aluminum weighs roughly one-third as much as steel. Therefore, engineers often select aluminum when weight reduction drives product performance

Common fabrication grades include 5052-H32, 5083, 6061-T6, and 6063 aluminum. Each alloy offers different combinations of strength, formability, and weldability. Consequently, engineers should evaluate performance requirements before choosing a specific grade.

Typical applications include:

• Vehicle structures
• Truck bodies
• Battery enclosures
• Robotics equipment
• Automation systems
• Aerospace components
• Transportation equipment

Aluminum also provides excellent corrosion resistance. As a result, many aluminum products require little or no protective coating. However, aluminum’s lower stiffness frequently requires larger structural members

Aluminum Advantages and Limitations

Advantages	Limitations
Lightweight	Higher material cost
Corrosion resistant	Lower stiffness
Excellent strength-to-weight ratio	Greater thermal expansion
Attractive appearance	More demanding welding procedures
Often requires no coating	Increased distortion sensitivity

High-Strength and Low-Alloy Steels

High-strength low-alloy (HSLA) steels provide greater strength than conventional carbon steels. Therefore, engineers can often achieve equivalent performance with less material. As a result, HSLA materials support weight reduction while maintaining structural capacity.

These materials often appear in:

• Heavy equipment
• Construction machinery
• Mining equipment
• Transportation systems
• Structural applications

However, high-strength steels demand greater attention during welding. Engineers must consider preheat requirements, cooling rates, hydrogen control, and weld procedure development. Consequently, fabrication becomes more complex than traditional carbon steel applications.

Material Selection by Application

Design Priority	Recommended Material
Lowest cost	Carbon Steel
Corrosion resistance	Stainless Steel
Lowest weight	Aluminum
High stiffness	Carbon Steel
Food-grade equipment	Stainless Steel
Washdown environments	Stainless Steel
Transportation equipment	Aluminum
Heavy industrial equipment	Carbon Steel or HSLA Steel
Structural efficiency	HSLA Steel

Material selection should support the product’s operating environment, manufacturing method, performance goals, and expected service life. As a result, engineers achieve better overall value than focusing on material price alone.

Weldability Considerations

Not every metal welds equally well. Therefore, weldability should remain a major factor during material selection. Poor weldability can increase labor costs, reduce quality, and extend production schedules.

Relative Weldability Comparison

Material	Relative Weldability
Carbon Steel	Excellent
Stainless Steel	Good to Excellent
Aluminum	Good
HSLA Steel	Moderate to Good

Several factors influence weldability:

• Material chemistry
• Material thickness
• Joint design
• Heat input requirements
• Cooling rates
• Welding process selection
• Hydrogen control requirements

Furthermore, engineers should verify that selected materials align with available welding processes and supplier capabilities. This step reduces manufacturing risk early in the design phase.

Corrosion, Weight, and Cost Tradeoffs

Every material selection requires tradeoffs. Consequently, engineers must balance performance, manufacturability, and cost.

Material Comparison

Characteristic	Carbon Steel	Stainless Steel	Aluminum
Material Cost	Lowest	Moderate to High	High
Weight	Highest	High	Lowest
Corrosion Resistance	Low	Excellent	Excellent
Weldability	Excellent	Good to Excellent	Good
Fabrication Cost	Lowest	Higher	Higher
Typical Finish	Paint or Coating	Often None	Often None
Common Use	Industrial Equipment	Food, Medical, Chemical	Transportation, Automation

Carbon steel usually delivers the lowest upfront manufacturing cost. Stainless steel often reduces maintenance costs through superior corrosion resistance. Aluminum decreases weight and can improve transportation efficiency. Meanwhile, HSLA steels improve structural efficiency where strength drives design decisions.

Ultimately, successful material selection focuses on total lifecycle value. Therefore, engineers should evaluate strength, corrosion exposure, weight targets, fabrication requirements, and long-term operating costs before making a final decision.

5. Weld Joint Design Fundamentals

The Five Basic Weld Joint Types

Nearly every welded assembly begins with one of five basic joint configurations. These joint types define how two components meet before welding begins. Furthermore, joint selection affects strength, weld volume, distortion, accessibility, inspection, and manufacturing cost. Therefore, engineers should select the simplest joint that satisfies the structural requirements.

The five fundamental joint types include:

These configurations form the foundation of almost every fabricated weldment, from machine frames and enclosures to structural steel assemblies and industrial equipment.]

Butt Joints

A butt joint joins two components in the same plane. The edges align and meet end-to-end before welding begins. As a result, butt joints create a smooth transition between connected materials.]

Engineers frequently use butt joints in plate weldments, tubing, pipe systems, and structural assemblies. In many applications, butt joints provide excellent load transfer because forces move directly through the connected members. Consequently, butt joints often deliver the highest structural efficiency among common joint types.

Depending on material thickness, a butt joint may use square, bevel, V-groove, J-groove, or U-groove preparation. These preparations help achieve the required penetration and weld quality.

Tee Joints

A tee joint forms when one component sits perpendicular to another component. Together, the members create a shape that resembles the letter “T.” Consequently, tee joints appear throughout welded structures and fabricated assemblies.

Manufacturers commonly use tee joints in machine frames, support brackets, structural members, and equipment bases. Furthermore, tee joints frequently use fillet welds because they require minimal joint preparation and offer good manufacturing efficiency.

Engineers should pay careful attention to load paths when designing tee joints. Proper weld sizing and placement improve load transfer while minimizing unnecessary weld volume.

Lap Joints

A lap joint forms when one component overlaps another component. The weld joins the overlapping surfaces together. As a result, lap joints provide a simple and practical solution for many sheet metal applications.

Manufacturers commonly use lap joints in sheet metal assemblies, enclosures, guards, and light structural fabrications. Additionally, lap joints usually require less precise fit-up than butt joints. Therefore, they often simplify fabrication and assembly.

However, engineers should consider potential moisture traps and corrosion concerns when designing lap joints for outdoor environments. Proper drainage and finishing practices help reduce these risks.

Corner Joints

A corner joint joins two members at a corner and creates an L-shaped configuration. Manufacturers often use corner joints in products that require enclosed shapes or box-style construction.

Common applications include electrical enclosures, cabinets, machine covers, battery enclosures, and sheet metal housings. Furthermore, corner joints support both fillet welds and groove welds depending on structural requirements.

Good corner joint design provides adequate access for welding and inspection. Therefore, engineers should avoid overly tight geometries that restrict torch access.

Edge Joints

An edge joint joins parallel edges located next to one another. Engineers commonly use edge joints in thin-gauge sheet metal applications where loads remain relatively low.

Manufacturers often use edge joints for edge reinforcement, sheet metal products, and specialized enclosure components. However, edge joints generally provide lower structural strength than butt or tee joints. Therefore, engineers rarely use them in heavily loaded structures.

Successful edge joint designs focus on alignment, appearance, and manufacturability rather than maximum load capacity.

Fillet Welds vs Groove Welds

Most fabricated weldments use either fillet welds or groove welds. Although both join materials together, they serve different engineering purposes.

A fillet weld creates a roughly triangular cross-section between two surfaces. Manufacturers commonly apply fillet welds to tee joints, lap joints, and corner joints. Furthermore, fillet welds require minimal joint preparation and support faster production. Consequently, they represent the most common weld type in industrial fabrication.

A groove weld fills a prepared groove between components. Engineers often specify groove welds when greater penetration, higher load transfer capability, or improved fatigue performance becomes necessary. However, groove welds typically require additional preparation and greater weld volume. As a result, fabrication costs often increase.

The most economical solution usually uses the simplest weld that safely satisfies design requirements. Therefore, engineers should avoid specifying groove welds when fillet welds provide adequate performance.

Full Penetration vs Partial Penetration Welds

One of the most important weld design decisions involves penetration requirements. Engineers must determine whether complete penetration truly supports the application.

A Full Joint Penetration (FJP) weld extends through the entire joint thickness. Engineers often specify FJP welds for fatigue-sensitive structures, highly loaded components, and critical structural applications. As a result, these welds provide maximum load transfer capability.

A Partial Joint Penetration (PJP) weld penetrates only part of the joint thickness. Many industrial fabrications use PJP welds because they meet performance requirements while reducing weld volume and fabrication cost. Consequently, PJP welds often deliver the best balance between strength and manufacturability.

Engineers should avoid specifying full penetration welds without a clear technical justification. Otherwise, manufacturing costs may increase without improving performance.

Designing for Strength and Reliability

Strong weldments begin with effective joint design. Therefore, engineers should focus on load paths before choosing weld sizes. Forces should flow naturally through the structure with minimal stress concentrations.

Good weldment design includes:

• Smooth geometry transitions
• Appropriate weld sizing
• Accessible welding locations
• Accessible inspection locations
• Reduced weld volume
• Balanced weld placement
• Realistic manufacturing tolerances

Furthermore, engineers should place welds away from peak stress locations whenever possible. This practice helps improve fatigue performance and long-term reliability.

Many welded failures originate from poor design rather than poor workmanship. Consequently, successful weldments balance structural performance, manufacturability, distortion control, inspection access, and lifecycle cost. When these factors work together, welded structures achieve both reliability and economic efficiency.