Stress Relief Furnaces for Boiler Manufacturers

In the boiler manufacturing industry, structural integrity under pressure and thermal stress is non-negotiable. Whether fabricating fire-tube boilers, water-tube units, economizers, superheaters, or pressure drums, stress relief heat treatment is a crucial step to ensure durability, dimensional stability, and compliance with design codes like ASME Section I, Indian Boiler Regulations (IBR), and EN 12952. At Maan Global Industries, we engineer custom stress relief furnaces for boiler manufacturers to meet the industry’s high-temperature stress-relieving demands. Our systems are designed for large shell diameters, heavy wall thicknesses, and long welded seams, making us a trusted partner for both domestic and international boiler plants.

furnaces for boiler manufacturers

Post Weld Heat Treatment Furnace Manufacturer


Why Is Stress Relief Necessary in Boiler Manufacturing?

Welding during the fabrication of boiler shells, headers, and steam drums introduces high levels of residual stress due to rapid heating and cooling cycles. This residual stress can lead to:

  • Distortion and warping of boiler shells during further assembly

  • Crack initiation in weld zones, especially under cyclic pressure/temperature

  • Reduced fatigue life, especially in high-temperature/high-pressure boilers

  • Failure to meet regulatory inspection (NDT, hydro tests, or PWHT certification)

Stress relief furnaces for boiler manufacturers help mitigate these issues by reheating the welded component to a subcritical temperature—typically between 580°C and 700°C—to allow internal stresses to redistribute and relax without changing the material’s microstructure.

Tempering Furnace Manufacturer

Roller Hearth Furnace Manufacturers


Key Benefits of Stress Relief in Boilers

  • Removes harmful tensile stresses from weld zones

  • Improves toughness and ductility in heat-affected zones (HAZ)

  • Ensures structural dimensional stability

  • Enhances long-term service performance under pressure and thermal cycling

  • Enables compliance with ASME PWHT charts and IBR norms

Post-weld heat treatment (PWHT) is mandatory for boiler drums and high-pressure parts above certain thicknesses (e.g., >20mm), especially in carbon and alloy steels.


Types of Stress Relief Furnaces for Boiler Fabrication

At Maan Global, we supply a wide range of stress relief furnace configurations designed for the geometry, volume, and handling needs of boiler manufacturing.

1. Bogie Hearth Stress Relief Furnace

  • Description: A walk-in type furnace with a mobile trolley (bogie) that rolls in and out for loading heavy boiler parts.

  • Applications: Large boiler shells, steam drums, complete assembled bodies.

  • Heating Options: Gas fired or electric Furnace.

  • Benefits: High load capacity, uniform heating, easy loading of long/heavy structures.

2. Pit Type Stress Relief Furnace

  • Description: A vertical furnace where components are lowered from the top. Ideal for cylindrical components.

  • Applications: Headers, nozzles, large-diameter pipes.

  • Benefits: Saves floor space, ideal for tall parts, better vertical temperature flow.

3. Box / Chamber Furnace

  • Description: A horizontally loaded, front-access stress relief furnace.

  • Applications: Tube sheets, small drums, flanges, brackets.

  • Benefits: Fast cycle changes, compact design, suitable for shop floor use.

4. Continuous Conveyor Furnace (for small batch boiler accessories)

  • Description: Belt or roller conveyor for continuous stress relief of fasteners, clips, or boiler brackets.

  • Benefits: High throughput, minimized handling.


Technical Table – Typical Stress Relief Parameters for Boilers

Parameter Typical Range Notes
Material Grades SA 516 Gr 60/70, SA 387, SA 192 Carbon steel, Cr-Mo steel common in boiler fabrication
Stress Relief Temperature 580°C to 700°C Depends on alloy content and code compliance
Heating Rate 30–100°C/hour Per ASME guidelines, slower for thicker parts
Soak Time 1 hour per 25 mm wall thickness Minimum 30 min; adjusted for total thickness
Cooling Rate Max 100°C/hr down to 300°C, then air Controlled to avoid thermal shock/distortion
Atmosphere Air (optional: nitrogen) Inert used for sensitive alloy steel parts
Control System PID / PLC + SCADA Multi-zone control, data logging, remote monitoring
Compliance ASME Section I, IBR, ISO 9001 Thermocouple placement, calibration, and data archiving required

Industrial Applications – Boiler Parts Requiring Stress Relief

Component Description Recommended Furnace Type
Boiler Shells Large longitudinally welded pressure shells Bogie hearth gas fired furnace
Steam Drums Horizontal high-pressure drums Bogie hearth or pit type
Headers & Manifolds Multi-nozzle thick-wall welded parts Pit type furnace
Tube Sheets Forged plates with drilled holes Box furnace
Superheater Coils Heat transfer coils with welds Electric or gas batch furnace
Water Walls Panel assemblies with welding across tubes Continuous or large chamber type
Nozzles & Flanges Weld-on pipe fittings Electric batch furnace

Standards and Quality Compliance for Boilers

Our stress relief furnaces for boiler manufacturers comply with:

Standard Description
ASME Section I PWHT Post-weld heat treatment required above threshold thickness and alloys
IBR – India Mandatory thermal cycle records, calibration reports, and approval testing
ISO 9001:2015 Process control, traceability, and quality assurance
DIN / EN 12952 European boiler design standards for power plants

We provide complete documentation packages including thermal cycle charts, uniformity surveys, and SOPs for inspection authorities and customer audits.


System Design and Furnace Features

Maan Global furnaces are engineered with the following features:

  • Chamber Sizes: From 1500 mm x 1500 mm to 8000 mm x 8000 mm

  • Loading Mechanism: Bogie trolley, crane-guided platform, or forklift compatible

  • Insulation: Ceramic fiber lining or refractory brick depending on operating cycles

  • Burner System: Fully modulating with O₂ sensor and flame failure safety (gas fired units)

  • Electrical System: PLC + HMI with thermocouple feedback loop and ramp-hold programming

  • Energy Efficiency: Optional regenerative burners or waste heat recovery available


Optional Add-Ons for Boiler Clients

  • SCADA / cloud monitoring integration

  • Pressure port compatibility for vessel-mounted sensors

  • Backup generator support for uninterrupted thermal cycles

  • Temperature uniformity certification kit

  • AMCs, calibration, and operator training


Global Installations – Maan Global Reach

As a trusted name in stress relief furnace manufacturing, we’ve supplied systems to:

  • India: Hyderabad, Chennai, Pune, Ahmedabad, Howrah

  • Saudi Arabia: Jubail, Dammam, Riyadh

  • UAE: Sharjah, Dubai, Abu Dhabi

  • Africa: Kenya, Tanzania, Nigeria, Ghana

  • Bangladesh & Nepal: IBR-certified furnace setups


Contact the Trusted Supplier of Stress Relief Furnaces for Boiler Manufacturers

Whether you’re fabricating IBR-approved high-pressure steam boilers, waste heat recovery units, or utility boilers, Maan Global Industries is your ideal partner for stress relief furnaces for boiler manufacturers.

We deliver precision-controlled, ASME/IBR-compliant furnace systems tailored to your plant layout, material specs, and process load.

Email: mail@maanglobalindustries.com
Call/WhatsApp: +91-8882490101

Stress Relief Furnaces for Boiler Manufacturers

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