Flanges

Industrial Pipe Flanges manufacturer in UAE

What are Pipe Flanges?

A pipe flange is a protruded rim that help in making a connection between two or more piping equipment. Pipe Flanges can combine or dismantle piping systems or mobile installations to create a transition between dissimilar materials. These Flanges allow room for easy access, cleaning, and inspection. They can be bolted, welded, or screwed following different procedures. There are different Flange Types that are designed to suit different project requirements.

Steel flange material and grades

Steel Flanges available in various material and grades as per ASME B16.5 specification

 

 

 

 

 

 

Types of flanges

Types of flanges

Looking for high pressure flange types? Click on the flange types for specification and dimensions

Why to pay more if you can get the same material with MTC at quite lower price, find here only Verified suppliers & stockists

 

Buy Pipe Flanges in Class 150/300/900 and 2500 for refinery & petrochemical industry in Middle East

Flange standard

Click on the below standard to view the steel flange dimensions and weights

Manufacturing methods of steel flanges

Types of Flange faces

Raised Face (RF) Flat Face (FF) Ring-Type Joint (RTJ)
Marking symbol : ASME B16.5 RF

Height of raised face

  • 1.6 mm (1/16 inch for ANSI class 150 and 300 flange
  • 6.4 mm (1/4 inch) for 400, 600, 900, 1500 and 2500 class
Marking symbol : ASME B16.5 FF Marking symbol : ASME B16.5 RTJ

  • Suitable for high pressure: Class 600 and above
  • Installed in high temp services: above 800°F (427°C)
Tongue-and-Groove (T&G) Male-and-Female (M&F)
Marking symbol : ASME B16.5 T&G Marking symbol : ASME B16.5 M&F

  • female face is 3/16″ deep
  • male face is1/4″ high

Types:

  • Small M&F Flanges
  • Large M&F Flanges

Flange bolt hole number & diameter

Flange class Numbers of bolt Diameter of bolt (in mm)
150lb 12 25.4
300 16 28.6
400 16 34.9
600 20 34.9
900 20 38.1
1500 16 54
2500 12 73

Steel flange thickness

  • Sch 10
  • Sch 20
  • Sch 30
  • STD Wall
  • Sch 40
  • Sch 60
  • EXT Hvy
  • Sch 80
  • Sch 100
  • Sch 120
  • Sch 140
  • Sch 160
  • XX Hvy

Torque sequence for steel flanges

Type Sequence for Bolt/ Stud Tightening
4 bolt flanges 1, 3, 2, 4
8 bolt flanges 1, 5, 3, 7, 2, 6, 4, 8
12 bolt flanges 1, 7, 4, 10, 2, 8, 5, 11, 3, 9, 6, 12
16 bolt flanges 1, 9, 5, 13, 3, 11, 7, 15, 2, 10, 6, 14, 4, 12, 8, 16
20 bolt flanges 1, 11, 6, 16, 3, 13, 8, 18, 5, 15, 10, 20, 2, 12, 7, 17, 4, 14, 9, 19
24 bolt flanges 1, 13, 7, 19, 4, 16, 10, 22, 2, 14, 8, 20, 5, 17, 11, 23, 6, 18, 12, 24, 3, 15, 9, 21
28 bolt flanges 1, 15, 8, 22, 4, 18, 11, 25, 6, 20, 13, 27, 2, 16, 9, 23, 5, 19, 12, 26, 3, 17, 10, 24, 7, 21, 14, 28
32 bolt flanges 1, 17, 9, 25, 5, 21, 13, 29, 3, 19, 11, 27, 7, 23, 15, 31, 2, 18, 10, 26, 6, 22, 14, 30, 8, 24, 16, 32, 4, 20, 12, 28

Flange classes and ratings

ASME B16.5 ASME B16.47 Series A ASME B16.47 Series B ASME B16.36
  • 150
  • 300
  • 600
  • 900
  • 1500
  • 2500 PSI
  • 150
  • 300
  • 600
  • 900
  • 1500
  • 2500 PSI
  • 75
  • 150
  • 300
  • 400
  • 600
  • 900
  • 1500
  • 2500 PSI
  • 300
  • 400
  • 600
  • 900
  • 1500
  • 2500 PSI

Steel flanges hs code

  • 7307.21 (for SS)
  • 7307.29 (for SS)
  • 7307.91 (For CS)
  • 7307.99 (For CS)
  • 7307.91 (For Inconel)
  • 7307.99 (For Inconel)

Steel flanges markings

  • Marking on Cast flanges: ASME/ ASTM specification, grade, size, rating (class 150-2500) melt number and manufacturer / supplier logo
  • Plate flanges marking: ASME/ ASTM specification, grade, size, rating (class 150-2500) and manufacturer / supplier logo
  • Forged flanges marking: ASME/ ASTM specification, grade, size, rating (class 150-2500) and manufacturer / supplier logo
  • Ring-Joint Flanges marking: ring-groove number, letter R (like R93 to R105), size, and manufacturer / supplier logo

Maximum size of large diameter steel flanges

  • Standard for large dia: ASME B16.47
  • NPS 26 -NPS 60
    for larger sizes pls contact listed flanges suppliers in UAE

Types of high pressure flanges

  • Weld Neck Flanges (WN) : up to 2,500lbs
  • Slip-On Flanges (SO): up to 2,500lbs
  • Blind Flanges (BL): up to 2,500lbs
  • Threaded Flanges (TH): up to 2,500lbs
  • Socket Weld Flanges (SW): up to 2,500lbs
  • Lap Joint Flanges (LJ): up to 2,500lbs
  • Raised Face (RF) and Flat Face (FF) flanges: up to 2,500lbs

Flange specification

High temperature flanges

Compare the temperature of steel flanges mostly installed in industrial sectors such as oil & gas, petrolium, refinery, petrochemical plants and others

Grade Steel flange temperature range
ASTM A182 F304 up to 870°C (1,600°F)
A182 Gr.F304L up to 425°C
ASTM A182 F316 up to 870°C (1,600°F)
ASTM A182 F11 F5 /F9/ F22 -29°C (-20°F) to 593°C (1,100°F)
Inconel Flanges up to 1,090°C (2,000°F)
Hastelloy Flanges up to 1,095°C (2,003°F)
Titanium Flanges up to 540°C (1,000°F)
ASTM A105 flange / A515 Gr.70/ A350 LF2 / A216 Gr.WCB up to 425°C
A350 LF6 Cl 1 up to 260°C.
A537 Cl.1 up to 370°C

Flange Facing

Flange face accordance to 6.1.4.1 and 6.1.4.2

Class Flange face
75, 150, 300 2 mm (0.06 in.) raised face
400, 600, 900 7 mm (0.25 in.) raised face

Tolerances of steel flanges

OD raised face ±2 mm (±0.08 in.)
Raised face flanges- 2 mm (0.06 inch) ±0.5 mm (±0.02 in.)
Raised face flanges- 7 mm (0.25 in.) ±2 mm (±0.08 in.)

Flange thickness tolerances

Thickness (mm/ inch) Tolerances (in inch) Tolerances (in mm)
tf ≤ 25 mm (1.0 in.) +0.12 “., -0.00 “ +3.0 mm, -0.0 mm
25 mm (1.0 in.) < tf ≤ 50 mm (2.0 in.) +0.19 “, -0.00 “ +5.0 mm, -0.0 mm
50 mm (2.0 in.) < tf ≤ 75 mm (3.0 in.) +0.31 “, -0.00 “ +8.0 mm, -0.0 mm
tf > 75 mm (3.0 in.) +0.38 “, -0.00 “ +10.0 mm, -0.0 mm

Steel flanges supporting material

  • Metallic Gaskets as per ASME B16.20
  • Ring-Joint
  • Spiral-Wound
  • Jacketed
  • Nonmetallic Flat Gaskets as per ASME B16.21
  • High Temp Gasket Material for above 500 °C (PTFE)

Sacrificial flange material

  • Zinc
  • Aluminum alloy
  • Magnesium
  • Galvanized steel

What is the purpose of a flange in refinery & petrochemical industry?

A flange is used to efficiently connect pipes, tubes, valves, pumps, and other equipment in the refinery and petrochemical industry. Industrial Pipe Flanges can handle different pressure equipment. Their easy maintenance and installation process gives them an edge in this industry. Find steel flanges suppliers in UAE who make use of the best material and are available in different dimensions.

 

What is RF in flange?

An RF flange is a common flange type in the industry and is easy to identify. The flanges have a raised surface that is raised above the bolting circle where a gasket is placed. These Steel Flanges can make use of a wide combination of gasket designs. They ensure strong sealing and can handle higher pressure media in the system.

 

Looking for flange stockist in Dubai? Get the quotes from verified Flat Face & Raised Face flanges manufacturers in UAE

 

Raised Face Flange vs Flat Face Flange

A flange can be produced either in a raised or flat face specification. A Raised Face Flange has a raised face above the bolting area that allows it to securely seal with a gasket. They ensure a strong sealing and thereby increase the pressure containment capability of the joint.

A Flat Face Flange has a gasket surface that is similar to the face of the bolting circle. These flanges don’t have the same strength as RF flanges and are preferred for lower pressure applications.

Check Flange Types, dimensions, class and Flange Joint pressure rating chart as per ASTM/ ASME/ EN/ DIN/ JIS standards

steel Flanges

What is the advantage of flange joint?

A flange joint is utilized to easily assemble piping equipment in tight spaces. The Flange Joint has excellent flexibility and can be easily maintained without requiring the dismantling of the entire pipe. They securely seal the equipment allowing for rigorous hydraulic movement to take place in the system.

Is RF and RTJ flanges can join together?

No, because RTJ flanges comes with grooved surface so even you can not use flat gasket to join RF and RTJ