Boiler Swaged Tubes

Product Description

Boiler Swaged Tubes Explained

Swaged tubes in a boiler are tubes that have been mechanically reduced in diameter at one or both ends to allow a snug fit into headers, drums, or other tubes of smaller diameter. Swaging is done to ensure tight mechanical joints, promote better weld connections, or allow for expansion fitting.

What Are Swaged Boiler Tubes?

• Swaging is a metal forming process that reduces the outer diameter (OD) of a tube by cold or hot mechanical deformation.

• In boilers, swaged tube ends are used when the tube needs to connect to a drum hole or header that is smaller in diameter than the tube body.

• Its a common practice in water-tube boilers, especially in superheater, economizer, and water wall tubes.

Purpose of Swaging:

1. Join different tube sizes (e.g., 2" tube swaged down to fit a 1.5" header)

2. Ease of installation in tight or restricted boiler spaces

3. Provide smooth internal transitions to reduce turbulence

4. Prepare tube ends for welding, expansion, or rolling into drums or headers

Swaging Process:

Method	Description
Cold Swaging	Performed at room temperature using dies and hydraulic or mechanical presses
Hot Swaging	Done at elevated temperatures to reduce force and avoid cracking, especially in alloy steels
Rotary Swaging	Tube is inserted into rotating dies that hammer the outside to reduce diameter
Tapered Swaging	Used to form a smooth tapered profile at the end of the tube

Tube Materials:

Swaging can be performed on most boiler tube materials:

• Carbon steel (e.g., SA-210 Gr A1)

• Alloy steel (e.g., T11, T22)

• Stainless steel (e.g., TP304, TP316)

• The material must maintain mechanical integrity after deformation.

Inspection & Quality Control:

• Dimensional checks (OD, taper, wall thickness)

• Visual inspection for cracks or scoring

• Dye penetrant or magnetic particle testing for surface defects

• Hardness tests (especially after cold swaging of hardened steels)

Best Practices:

• Use proper lubrication to reduce surface damage during swaging

• Allow post-forming heat treatment if required (for alloy steels)

• Ensure uniform wall thickness after swaging

• Select the correct die angle and taper for smooth transition

Typical Dimensions:

• Original Tube OD: 1.5" to 3"

• Swaged End OD: Reduced by 1/8" to 1/2", depending on fit

• Swage Length: Usually 2" to 6", or custom per spec

Precision Manufacturing and Customization

Boiler Swaged Tubes are produced through advanced cold drawn or hot finished processes, followed by precise swaging to achieve reduced or specialty ends. Each tube can be customized for diameter, thickness, length, and end type in accordance with specific project drawings and standards, ensuring a tailored fit for high-pressure systems.


Durability and Superior Performance

These tubes are engineered to meet stringent tensile strength and high-pressure requirements of industrial boilers. The superior quality of carbon and alloy steel ensures lasting reliability, while the protective black paint or anti-rust oil coating safeguards against corrosion and extends service life.


Versatile Applications and Efficient Supply

Used extensively in boilers, heat exchangers, and super heaters, Boiler Swaged Tubes are essential for critical high-pressure applications. As a trusted importer, manufacturer, supplier, and trader, we ensure rapid delivery of customized orders across India, meeting diverse technical and operational demands.