Careers Automated Field Weld Overlay
Extend equipment life and maximize operational reliability with IGS’s automated weld overlay solutions.
IGS delivers high-performance automated field weld overlay services to protect and restore critical equipment in the world’s harshest operating environments. Our automated welding process applies a metallurgically bonded corrosion-resistant alloy (CRA) layer that protects pressure vessels, columns, boilers, and other components from erosion, chemical attack, and high-temperature degradation.
Where required, weld overlay can also restore wall thickness and reinforce the pressure boundary, making it a critical solution for both corrosion protection and structural integrity.
What Problems Does Weld Overlay Solve?
Weld overlay is applied when asset degradation goes beyond surface damage and requires a permanent, metallurgically bonded solution.
It is most effective in addressing:
- Corrosion and chemical attack (H₂S, CO₂, chlorides, acids)
- Erosion and high-velocity wear
- Wall thinning and loss of pressure boundary integrity
- Thermal degradation in high-temperature environments
Unlike coatings or thermal spray, weld overlay:
- Changes the exposed metallurgy of the component
- Provides a fully bonded alloy layer
- Can restore thickness while adding corrosion resistance
When to Use Weld Overlay vs Other Solutions
Selecting weld overlay depends on whether structural integrity and corrosion resistance must be addressed simultaneously.
Weld Overlay (WOL)
Used when:
- Wall thickness must be restored
- Pressure boundary integrity is at risk
- A long-term, permanent solution is required
Thermal Spray / HVTS®
Used when:
- Corrosion protection is required
- Structural thickness remains adequate
- Faster, lower-heat solutions are preferred
Replacement
Required when:
- The asset cannot meet fitness-for-service (FFS) requirements
- Integrity cannot be restored through repair
IGS follows an integrity-first approach, ensuring structural adequacy before applying corrosion protection.
Why Weld Overlay Performance Depends on Process Control
Weld overlay performance is not defined by thickness alone, it depends on precise control of heat input, dilution, and metallurgical stability.
Heat Input — Controls Integrity
Excessive heat can:
- Degrade base material properties
- Increase residual stress
- Raise susceptibility to cracking
Controlled heat input ensures a stable bond without compromising the pressure boundary.
Dilution — Controls Corrosion Resistance
Dilution determines how much base metal mixes with the overlay alloy.
- High dilution → reduced corrosion resistance
- Low, controlled dilution → maintains alloy performance
HAZ Control — Controls Long-Term Reliability
Poor heat-affected zone (HAZ) control can lead to:
- Hardness spikes and embrittlement
- Increased cracking risk
- Localized corrosion near weld boundaries
Why This Matters
Long-term overlay performance depends on:
- Stable surface chemistry
- Predictable stress distribution
- Defect-free metallurgical bonding
Even a thick overlay can fail prematurely if these factors are not controlled.
Limitations and Field Considerations
Weld overlay is a powerful solution, but it is not always the right choice.
Field application introduces challenges that must be managed:
- Heat input and distortion risks
- Dilution control variability in field conditions
- Access and geometry constraints
- Extended execution time compared to coatings
- PWHT and thermal management limitations
- Inspection complexity (UT, PMI, hardness mapping)
In corrosion-only cases, weld overlay may introduce unnecessary cost, risk, and downtime compared to alternative technologies.
Comprehensive Overlay Capabilities
Our automated welding services are optimized for precision and efficiency in field environments, enabling the restoration and enhancement of critical assets without costly replacements.
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Custom weld overlay protection for pressure vessels, towers, reactors, and other process equipment
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Internal diameter (ID) nozzle overlay from 2″ diameter
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Boiler waterwall protection for long-term thermal and corrosion resistance
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Overlay solutions tailored for carbon steel, alloy steel, and other base materials
Technical Advantages
Our weld overlay cladding process offers unmatched reliability and performance in demanding industrial conditions.
Controlled Dilution: Achieve required chemistry as specified by industry codes and service conditions, ensuring overlay integrity and corrosion resistance
Minimal Distortion: Low heat input protects component geometry
Metallurgical Bonding: Superior adherence to the substrate
Process Consistency: Automated process and controlled welding parameters ensure uniform overlay thickness and quality
Versatility: Compatible with various base materials and overlay alloys
– Base materials: carbon and alloy steels, nickel based alloy, monel
– Overlay materials: SS 309L, 316L, 317L, 312, alloy 625, 622, and custom solutions
Field-Proven Applications
Our weld overlay process is designed to meet the corrosion, temperature, and wear challenges in critical equipment across multiple sectors:
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Waste-to-Energy & Biomass Boilers: Protection against high temperatures, corrosive gases, ash particles, chlorides and sulfates corrosion
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Refining & Petrochemical: Protection against naphtenics, H2S, CO2, HCl, MIC, and Ammonia, among others
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Chemical Processing: Acid and erosion resistance
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Pulp & Paper: Black liquor recovery boiler and continuous digester protection
Key Benefits
- Extended Asset Life: Significantly longer service intervals
- Corrosion Rate Control: Halt or drastically slow corrosion rates
- Reduced Maintenance Costs: Avoid premature equipment replacement and associated downtime costs
- Schedule Control: Field application expertise
- Quality Assurance: 100% inspection with UT, PT, MT, PMI, VT testing
- Global Experience: Projects completed in over 50 countries
- Turnaround Excellence: Specialized project management for critical path turnaround operations
- Accelerated Execution: Our thorough planning and preparations enable faster application with minimal delays
- Specialty Alloy Expertise: In-house laboratory testing and pre-qualification of high-performance alloys ensures optimal performance
Meet Our Welding Experts
IGS brings together a global team of specialists in welding engineering, metallurgy, and field execution.
Each expert contributes to:
- Procedure qualification and welding strategy
- Alloy selection and corrosion compatibility
- Failure analysis and repair design
- On-site quality assurance and execution
Why Choose IGS?
At IGS, we deliver measurable value through our proprietary technologies, fostering long-lasting partnerships built on efficient execution and excellence.
- Industry-Leading Technology: Proprietary Welding, Metalspray™, & HVTS® technologies ensure consistent quality
- Safety First: Industry-leading safety standards
- Trained Specialists: Full-time specialized workforce with extensive experience
- Proven Track Record: 40+ years’ experience across 500+ annual projects in 105 global locations
- Superior Project Management: Expert planning and execution that minimizes turnaround time
- Comprehensive Preparation: Our detailed planning process means we execute faster with fewer surprises
- Advanced Alloy Expertise: In-house laboratory for testing and pre-qualification of specialty alloys
Contact our team of experts to discuss your specific challenges.
Our Welding Services
Extend asset life and safeguard critical infrastructure with IGS’s industry-proven automated welding services
- Automated Field Overlay
- Weld Build-up
- Speciality Welding