Navigate the full flange technical reference below.
Flanges are mechanical connectors used to join pipes, valves, pumps and equipment in piping systems. They allow easy assembly and disassembly while maintaining a leak-tight seal under various pressure and temperature conditions.
Kennkrupps manufactures and supplies industrial flanges for oil & gas, petrochemical, power generation and process industries across India and internationally — as per ASME B16.5, ASME B16.47, EN 1092-1 and customer-specific drawings.
Butt-welded to pipe with full penetration weld. Best for high-pressure, high-temperature and cyclic service.
Pipe slides through and is fillet welded front and back. General purpose, easy alignment, medium pressure.
Solid disc bolted without a pipe connection. Used for terminations, isolation, testing and manways.
Pipe fits into a machined socket and is fillet welded. Ideal for small-bore high-pressure lines and hydraulics.
Screwed onto the pipe without welding. Suited to explosive areas, field assembly and low-pressure utility.
Used with a stub end for bolted assembly. Handles frequent disassembly and thermal expansion zones.
Connects two different pipe sizes without a separate reducer, with a built-in size transition.
Includes pressure tap holes for flow measurement with orifice plates in metering runs.
| Face Type | Description | Pressure Class | Gasket Type | Applications |
|---|---|---|---|---|
| Raised Face (RF) | 1.6mm (1/16") for 150–300#, 6.4mm (1/4") for 400#+ | 150# to 2500# | Spiral wound, non-asbestos, rubber | Most common; oil & gas, chemical, power |
| Flat Face (FF) | Entire face is flat, no raised portion | 150# to 300# | Full-face gaskets | Cast iron flanges, low-pressure water |
| Ring Type Joint (RTJ) | Precision-machined groove for metal ring gasket | 600# to 2500# | RTJ gaskets (oval/octagonal) | High-pressure oil & gas, refineries |
| Tongue & Groove (T&G) | Matching tongue and groove faces | 600# and above | Custom gaskets | Heat exchangers, special applications |
| Male & Female (M&F) | One flange has male face, other has female | 600# and above | Custom gaskets | Custom equipment, special designs |
| NPS (Inch) | DN (mm) | O (mm) | R (mm) | C (mm) | BC (mm) | No. Bolts | Bolt Size | Bolt Hole (mm) | Weight (kg) |
|---|---|---|---|---|---|---|---|---|---|
| 1/2" | 15 | 89 | 35 | 11 | 60 | 4 | M12 (1/2") | 16 | 0.8 |
| 3/4" | 20 | 98 | 43 | 11 | 70 | 4 | M12 (1/2") | 16 | 1.0 |
| 1" | 25 | 108 | 51 | 14 | 79 | 4 | M12 (1/2") | 16 | 1.3 |
| 1-1/4" | 32 | 117 | 64 | 16 | 89 | 4 | M12 (1/2") | 16 | 1.8 |
| 1-1/2" | 40 | 127 | 73 | 16 | 98 | 4 | M12 (1/2") | 16 | 2.1 |
| 2" | 50 | 152 | 92 | 16 | 121 | 4 | M16 (5/8") | 20 | 2.8 |
| 2-1/2" | 65 | 178 | 105 | 17 | 140 | 4 | M16 (5/8") | 20 | 3.8 |
| 3" | 80 | 191 | 127 | 19 | 152 | 4 | M16 (5/8") | 20 | 4.5 |
| 4" | 100 | 229 | 157 | 19 | 191 | 8 | M16 (5/8") | 20 | 6.2 |
| 5" | 125 | 254 | 186 | 21 | 216 | 8 | M20 (3/4") | 22 | 8.5 |
| 6" | 150 | 279 | 216 | 22 | 241 | 8 | M20 (3/4") | 22 | 10.2 |
| 8" | 200 | 343 | 270 | 24 | 298 | 8 | M20 (3/4") | 22 | 15.8 |
| 10" | 250 | 406 | 324 | 25 | 362 | 12 | M24 (7/8") | 26 | 22.5 |
| 12" | 300 | 483 | 381 | 25 | 432 | 12 | M24 (7/8") | 26 | 30.8 |
| 14" | 350 | 533 | 413 | 29 | 476 | 12 | M27 (1") | 30 | 42.5 |
| 16" | 400 | 597 | 470 | 30 | 540 | 16 | M30 (1-1/8") | 34 | 55.2 |
| 18" | 450 | 635 | 533 | 32 | 578 | 16 | M30 (1-1/8") | 34 | 68.5 |
| 20" | 500 | 699 | 584 | 33 | 635 | 20 | M33 (1-1/4") | 37 | 85.8 |
| 24" | 600 | 813 | 692 | 37 | 749 | 20 | M36 (1-3/8") | 41 | 125.5 |
| Temp (°C) | Class 150 (bar) | Class 300 (bar) | Class 600 (bar) | Class 900 (bar) | Class 1500 (bar) | Class 2500 (bar) |
|---|---|---|---|---|---|---|
| -29 to 38 | 19.6 | 51.1 | 102.1 | 153.2 | 255.3 | 425.5 |
| 100 | 17.7 | 48.0 | 96.0 | 144.0 | 240.0 | 400.0 |
| 200 | 16.0 | 45.1 | 90.2 | 135.3 | 225.5 | 375.8 |
| 300 | 14.3 | 41.4 | 82.8 | 124.2 | 207.0 | 345.0 |
| 400 | 12.1 | 35.7 | 71.4 | 107.1 | 178.5 | 297.5 |
| 425 | 11.4 | 33.8 | 67.6 | 101.4 | 169.0 | 281.7 |
| 450 | 10.5 | 30.8 | 61.6 | 92.4 | 154.0 | 256.7 |
| 500 | 8.4 | 24.5 | 49.0 | 73.5 | 122.5 | 204.2 |
| Material Grade | Specification | Temperature Range | Applications |
|---|---|---|---|
| Carbon Steel | ASTM A105, A350 LF2 | -29°C to 425°C | Oil & gas, water, steam, general service |
| SS 304 | ASTM A182 F304 | -196°C to 800°C | Chemical, food, general corrosion resistance |
| SS 304L | ASTM A182 F304L | -196°C to 800°C | Welded assemblies, chemical processing |
| SS 316 | ASTM A182 F316 | -196°C to 800°C | Marine, chemical, high corrosion resistance |
| SS 316L | ASTM A182 F316L | -196°C to 800°C | Welded, high corrosion, pharmaceutical |
| SS 310 | ASTM A182 F310 | -196°C to 1100°C | High-temperature furnace applications |
| SS 321 | ASTM A182 F321 | -196°C to 800°C | Stabilized, welded, high-temperature |
| SS 347 | ASTM A182 F347 | -196°C to 800°C | Stabilized, high-temperature service |
| Duplex F51 | ASTM A182 F51 | -50°C to 300°C | Offshore, seawater, high chloride |
| Super Duplex F53 | ASTM A182 F53 | -50°C to 300°C | High-pressure seawater, offshore |
| Alloy Steel F11 | ASTM A182 F11 | -29°C to 550°C | Power plants, high-temperature steam |
| Alloy Steel F22 | ASTM A182 F22 | -29°C to 550°C | Refineries, high-temperature service |
| Alloy Steel F91 | ASTM A182 F91 | -29°C to 600°C | Power generation, supercritical boilers |
| Inconel 625 | ASTM B564 N06625 | -196°C to 1000°C | Aerospace, extreme corrosion, high-temp |
| Hastelloy C276 | ASTM B574 N10276 | -196°C to 450°C | Chemical processing, severe corrosion |
| Monel 400 | ASTM B564 N04400 | -196°C to 450°C | Marine, chemical, hydrofluoric acid |
Oil refineries, petrochemical plants, natural gas transmission pipelines and power generation (thermal, nuclear, hydro).
Chemical and pharmaceutical processing, water treatment, desalination plants and marine/offshore platforms.
Pulp and paper, food and beverage processing, HVAC systems, and mining and mineral processing.
Certified manufacturing management system guaranteeing process control and traceability.
Pressure Equipment Directive 2014/68/EU and Indian Boiler Regulations approved manufacturing.
Mill Test Certificates EN 10204 3.1/3.2 with every shipment. TPI available as required.
Positive Material Identification and Ultrasonic Testing available on demand for critical service.
Sour service materials available per NACE MR0175 / MR0103 for oil & gas applications.
Every flange dimensionally verified and marked with grade, standard and lot traceability.
Our team can help with flange selection, specifications, custom dimensions, bulk orders and technical consultation.