Flanges Welding
Table of Content
- Three Parts of Flange Connection
- Weldable Flange Type
- Application Wise Flange Welding Type
- Types of Welding Used for Flanges
- Flanges Welding Techniques
- Pipe Flange Welding Procedure
- Common Challenges in Pipe Flange Welding
- Flanges Welding Machine
- Safety Considerations in Pipe Flange Welding
- Common Considerations Weld On Pipe Flange
- Marking On Welding Flange
- Class 150 Flange Bolt Chart
- Class 300 Flange Bolt Chart
- Class 600 Flange Bolt Chart
- Class 900 Flange Bolt Size
- Class 1500 Flange Bolt Torque
- Class 2500 Flange Bolt Torque
Flange welding joins pipes, flange, other steel components in high pressure systems sucha water pipelines and oil & gas. Weldable flange welding is a method used to attach a pipe flange to a pipe by melting metal. Welding flange typically used in the power generation, oil and gas, and chemical industries. Check belwo different types of flanges welding.
Three Parts of Flange Connection
3 main parts of flanged connection
- Gasket
- Pipe Flanges
- Bolting
| Flange Welding Type | Used for |
| THRF flange | suitable for non critical systems |
| BLRF flange | Useful in high pressure systems |
| SWRF flange | Small diameter applications |
| SORF flange | Low pressure applications |
| WNRF flange | Ideal for high temperature systems |
Application Wise Flange Welding Type
| Application | Description |
| Pharmaceutical | Clean piping systems |
| HVAC Systems | Heating and cooling |
| Shipbuilding | Marine piping systems |
| Water Treatment | Distribution and treatment systems |
| Power Plants | Water and fuel pipelines |
| Chemical Plants | Transportation dangerous fluids. |
| Oil and Gas Industry | Liquids and gases in pipelines |
Types of Welding Used for Flanges
Butt Welding
Socket Welding
Fillet Welding
- Shielded Metal Arc Welding
- Gas Metal Arc Welding
- Flux-Cored Arc Welding
- Gas Tungsten Arc Welding
Common Challenges in Pipe Flange Welding
Flanges Misalignment
Poor Weld Penetration
Cracking After Welding
Porosity in Welds
Distortion and Overheating
Safety Considerations in Pipe Flange Welding
- Safe Welding Practices
- Handling Hazardous Materials
- Personal Protective Equipment
Common Considerations Weld On Pipe Flange
- Outside Diameter
- Diameter of Bolt Circle
- Pipe Size
- Nominal Bore Size
- Wall Thickness
- Manufacturer Logo = Ramesh Group
- ASTM Material Code = Carbon Steel
- Material Grade = ASTM A105
- Service Rating = 150 LB
- Size = 6 Inch
- Thickness = SCH 80
- Heat Number = 4500068084
Ultimate Guide to Flange Bolt Chart in Class 150 to 2500
The length and diameter of flanges bolt are covered ASME B16.5 and ASME B16.47 standard.
| Size | Length of Machine Bolt | Length of RF Stud | UNC Size for Bolt | Bolts Number |
| DN600 | 150 | 170 | 1 1/4 | 20 |
| DN500 | 140 | 160 | 1 1/8 | 20 |
| DN450 | 125 | 145 | 1 1/8 | 16 |
| DN400 | 115 | 135 | 1 | 16 |
| DN350 | 115 | 135 | 1 | 12 |
| DN300 | 100 | 120 | 7/8 | 12 |
| DN250 | 100 | 115 | 7/8 | 12 |
| DN200 | 90 | 110 | 3/4 | 8 |
| DN150 | 85 | 100 | 3/4 | 8 |
| DN125 | 85 | 95 | 3/4 | 8 |
| DN100 | 75 | 90 | 5/8 | 8 |
| DN90 | 75 | 90 | 5/8 | 8 |
| DN80 | 75 | 90 | 5/8 | 4 |
| DN65 | 75 | 90 | 5/8 | 4 |
| DN50 | 70 | 85 | 5/8 | 4 |
| DN40 | 65 | 70 | 1/2 | 4 |
| DN32 | 55 | 70 | 1/2 | 4 |
| DN25 | 55 | 65 | 1/2 | 4 |
| DN20 | 50 | 65 | 1/2 | 4 |
| DN15 | 50 | 55 | 1/2 | 4 |
| Size | Length of Machine Bolt | Length of RF Stud | UNC Size for Bolt | Bolts Number |
| DN600 | 205 | 230 | 1 1/2 | 24 |
| DN500 | 185 | 205 | 1 1/4 | 24 |
| DN450 | 170 | 195 | 1 1/4 | 24 |
| DN400 | 165 | 190 | 1 1/4 | 20 |
| DN350 | 160 | 180 | 1 1/8 | 20 |
| DN300 | 145 | 170 | 1 1/8 | 16 |
| DN250 | 140 | 160 | 1 | 16 |
| DN200 | 120 | 140 | 7/8 | 12 |
| DN150 | 110 | 120 | 3/4 | 12 |
| DN125 | 110 | 120 | 3/4 | 8 |
| DN100 | 95 | 115 | 3/4 | 8 |
| DN90 | 95 | 110 | 3/4 | 8 |
| DN80 | 90 | 110 | 3/4 | 8 |
| DN65 | 85 | 100 | 3/4 | 8 |
| DN50 | 75 | 90 | 5/8 | 8 |
| DN40 | 75 | 90 | 3/4 | 4 |
| DN32 | 70 | 85 | 5/8 | 4 |
| DN25 | 65 | 75 | 5/8 | 4 |
| DN20 | 65 | 75 | 5/8 | 4 |
| DN15 | 55 | 65 | 1/2 | 4 |
| Size | Length of RF Stud | Bolts Number | UNC Sizefor Bolt |
| DN600 | 330 | 24 | 1 7/8 |
| DN500 | 285 | 24 | 1 5/8 |
| DN450 | 275 | 20 | 1 5/8 |
| DN400 | 255 | 20 | 1 1/2 |
| DN350 | 235 | 20 | 1 3/8 |
| DN300 | 220 | 20 | 1 1/4 |
| DN250 | 215 | 16 | 1 1/4 |
| DN200 | 190 | 12 | 1 1/8 |
| DN150 | 170 | 12 | 1 |
| DN125 | 165 | 8 | 1 |
| DN100 | 145 | 8 | 7/8 |
| DN90 | 140 | 8 | 7/8 |
| DN80 | 125 | 8 | 3/4 |
| DN65 | 120 | 8 | 3/4 |
| DN50 | 110 | 8 | 5/8 |
| DN40 | 110 | 4 | 3/4 |
| DN32 | 95 | 4 | 5/8 |
| DN25 | 90 | 4 | 5/8 |
| DN20 | 90 | 4 | 5/8 |
| DN15 | 75 | 4 | 1/2 |
| Size | Number Bolts | UNC Size for Bolt | Length of RF Stud |
| DN600 | 20 | 2 1/2 | 440 |
| DN500 | 20 | 2 | 350 |
| DN400 | 20 | 1 5/8 | 285 |
| DN300 | 20 | 1 3/8 | 255 |
| DN200 | 12 | 1 3/8 | 220 |
| DN100 | 8 | 1 1/8 | 170 |
| DN80 | 8 | 7/8 | 145 |
| DN50 | 8 | 7/8 | 145 |
| DN40 | 4 | 1 | 140 |
| DN25 | 4 | 7/8 | 125 |
| DN20 | 4 | 3/4 | 115 |
| DN15 | 4 | 3/4 | 110 |
| Size | Length Of RF Stud | Bolts Number | UNC Size For Bolt |
| DN600 | 615 | 16 | 3 1/2 |
| DN500 | 540 | 16 | 3 |
| DN400 | 445 | 16 | 2 1/2 |
| DN300 | 375 | 16 | 2 |
| DN200 | 290 | 12 | 1 5/8 |
| DN150 | 260 | 12 | 1 3/8 |
| DN100 | 195 | 8 | 1 1/4 |
| DN80 | 180 | 8 | 1 1/8 |
| DN50 | 145 | 8 | 7/8 |
| DN40 | 140 | 4 | 1 |
| DN25 | 125 | 4 | 7/8 |
| DN20 | 115 | 4 | 3/4 |
| DN15 | 110 | 4 | 3/4 |
| Size | Length Of RF Stud | Number Bolts | UNC Size for Bolt |
| DN300 | 540 | 12 | 2 3/4 |
| DN200 | 380 | 12 | 2 |
| DN100 | 255 | 8 | 1 1/2 |
| DN80 | 220 | 8 | 1 1/4 |
| DN65 | 195 | 8 | 1 1/8 |
| DN50 | 180 | 8 | 1 |
| DN40 | 170 | 4 | 1 1/8 |
| DN25 | 140 | 4 | 7/8 |
| DN20 | 125 | 4 | 3/4 |
| DN15 | 120 | 4 | 3/4 |
Weldable Flange Available in Various Materials and Grades
