BS 3293 Flanges | Large Diameter | Class 150-600

BS 3293 flanges are large-diameter carbon steel pipe flanges built for petroleum and process piping that need strong, standardized connections. The British Standard covers forged carbon steel slip-on welding and welding neck flanges for nominal sizes above 24 inches, usually from 26 inches up to 48 inches, and it works with higher pressure classes such as 150, 300, 400, and 600. The standard suits systems that carry oil, gas, steam, and other process fluids under demanding conditions. PM Industries manufactures, supplies, and stocks these flanges in a range of sizes, classes, and material grades.

Engineers choose BS 3293 flanges for their durability, tight dimensional accuracy, and the secure seal they hold when fitted with the right gasket and bolting. They are made in carbon steel, though the exact grade shifts with the service, temperature, and corrosion conditions of the line. Weld neck flanges tend to win in critical applications because they spread stress better and give strong structural support. Slip-on flanges get the call when easier installation and alignment matter more. Both follow established British flange dimensions, so they drop into existing systems without surprises.

You will find BS 3293 flanges in refineries, offshore installations, power stations, water systems, and heavy industrial piping networks where large connections have to stay sound for years. The design lowers leakage risk, carries high mechanical loads, and keeps compatibility with standard British dimensions. On large fabrication projects that consistency pays off, since standardized sizes make installation and maintenance quicker. Getting the face type, pressure rating, and material grade right is what delivers safe performance and long service life, and our team will help you confirm all three before you order.

PM Industries is a manufacturer, supplier, and stockist of BS 3293 flanges. We keep stock on hand, back every order with material test certificates, and ship to project deadlines. Tell us your size, class, face type, and material, and we will quote it.

Specification BS 3293 Flanges

Standards	ANSI/ASME B16.5, B16.48, ANSI Flanges, GOST Flanges, DIN Flanges, EN-1092, B16.47 Series A & B, ASME Flanges, EN Flanges, AWWA Flanges, BS Flanges.
JIS Standard	5K, 10 K, 16 K 20 K, 30 K, 40 K, 63 K
DIN FLANGES	DIN 2527, 2627, 2631, 2656, 2576, 2673, 2629, 2628, 2566, 2641, 2637, 2655, 2634, 2636, 2632, 2633, 2638, 2642, 2573, 2635.
Pressure Rating	Class 150 LBS, 300 LBS, 600 LBS, 900 LBS, 1500 LBS, 2500 LBS
Types	Threaded, Plate, Screwed, Forged.
Supporting material	Gasket, Ring Joint, Flange Bolts
Size range	1/2" (15 NB) to 48" (1200NB) DN10~DN5000
Production technique	Forged, machined and Heat treated
Available Flange Type	Weld Neck Flanges, RTJ Flanges, Slip On Flanges, Spectacle Blind Flanges, Flanges Gaskets, Square Flanges, Standard Insert Flanges, High Hub Blinds Flanges, Flat Flanges, forged flanges, Weldo / Nipo Flanges, Jacket Insert Flanges, Tongue groove Flanges, Blind Flanges, Socket Weld Flanges, Large diameter Flanges, Long Weld Neck Flanges, Spacer Blinds, SWRF Flanges, SORF Flanges, Angle Face Rings Flanges, Spades Ring Spacers Flanges, WNRF Flanges, Screwed Flanges, Insert Flanges, flanges bolts, cf flange, Lap Joint Flanges, ASME B16.36 Orifice Flanges, Plate Flange, Expander Flanges, Ring Type Joint Flanges, Loose Flanges, Reducing Flanges, puddle flange, Threaded Flanges, blank flange, vacuum flange.
Connect Type/ Flange Face Type	Ring Type Joint (RTJ), Flat Face (FF), Tongue & Groove, Small Male-Female (SMF), Lap-Joint Face (LJF), Raised Face (RF), Large Male-Female (LMF), Small Tongue.
Custom design	As per your drawing
Test	Direct-reading Spectrograph, X-ray detector, UItrasonic flaw detector, Magnetic particle detector, Hydrostatic testing machine.
Origin	Indian / USA / Korean / West Europe / Japan
Pressure Class	PN 6 TO PN 100
Thickness	Normal Pipe Size ≤ 18
Bore Diameter	Normal Pipe ≤ 10
High Temperature	Above 200°C (400°F) For Class 150 Or Above 400°C (750°F)
Low Temperature	Above -29 Degree C (−20°F)
Coating/Surface Treatment:	Zinc Plated, Anti-rust Paint, Oil Black Paint, Yellow Transparent, Cold and Hot Dip Galvanized.
European/African/Russian Standard Flanges	Available
Gaskets Types	Full Face, Metallic Ring, Flat Ring Gasket
Marking Standard	Name of Manufacturer
	Schedule
	Type of Flange Facing
	Pressure Class
	Nominal Pipe Size, etc
Test Certificates	EN 10204/3.1B, NACE MR0103, NACE MR0175
	Raw Materials Certificate
	100% Radiography Test Report
	Third Party Inspection Report, etc

Flange Type Available

Bs 3293 Flanges Weight

Nominal pipe size	Outside diameter of flange, O	Outside diameter, R	Thickness of flange min., C	Outside diameter of large end of hub, X	Length through hub, Y	Fillet radius	Flange bore, B	Diameter of bolt circle, D	Diameter of bolt holes	Number of bolt holes	Approxi-mate Weight kgs
26	869.95	742.95	50.80	723.90	85.73	6.35	666.75	806.45	34.93	24	104.09
28	927.10	793.75	52.39	781.05	87.31	6.35	717.55	863.60	34.93	28	118.94
30	984.25	857.25	53.98	831.85	88.90	6.35	768.35	914.40	34.93	28	134.56
32	1060.45	908.05	57.15	889.00	92.08	7.94	819.15	977.90	41.28	28	166.33
34	1111.25	958.85	58.74	939.80	93.66	7.94	869.95	1028.70	41.28	32	178.16
36	1168.40	1022.35	60.33	996.95	95.25	7.94	920.75	1085.85	41.28	32	201.15
38	1238.25	1073.15	60.33	1060.45	95.25	9.53	971.55	1149.35	41.28	32	234.77
40	1289.05	1123.95	63.50	1111.25	98.43	9.53	1022.35	1200.15	41.28	36	255.04
42	1346.20	1193.80	66.68	1168.40	101.60	9.53	1073.15	1257.30	41.28	36	289.32
44	1403.35	1244.60	66.68	1219.20	101.60	11.11	1123.95	1314.45	41.28	40	307.07
46	1454.15	1295.40	68.26	1270.00	103.19	11.11	1174.75	1365.25	41.28	40	327.20
48	1511.30	1358.90	69.85	1327.15	104.78	11.11	1225.55	1422.40	41.28	44	357.05