Plate Flanges Manufacturer

Q1. What is a plate flange?

A plate flange is a flat, circular steel plate (without a hub) drilled with bolt holes and welded to the end of a pipe to create a bolted connection. It is essentially a flat slip-on flange, widely used in low-to-moderate pressure piping for water, utility, chemical and process service, and is common in European (EN 1092-1), DIN and JIS standards.

Q2. What is the difference between a plate flange and a slip-on flange?

A plate flange is a flat plate with no raised hub, while a slip-on flange (ASME B16.5) has a short hub for added strength. Plate flanges are simpler and lower cost, used mainly in EN/DIN/JIS low-pressure piping; hubbed slip-on flanges carry higher pressure ratings. Both are slid over the pipe and fillet-welded.

Q3. What materials are plate flanges made from?

Plate flanges are made from carbon steel (A105), stainless steel (ASTM A182 F304/316/321/347/904L), duplex (F51/F53/F55), alloy steel (F5/F9/F11/F22/F91), LTCS (A350 LF2), Monel, Inconel, Hastelloy, Titanium and Copper Nickel. Carbon steel suits low-pressure utility; stainless and alloys are used for corrosive and higher-temperature service.

Q4. What standards cover plate flanges?

Plate flanges are made to EN 1092-1 (Type 01, PN2.5 to PN100), DIN 2573/2576/2501/2502/2503/2543, JIS B2220 (5K to 63K), and ASME B16.5 / B16.47 dimensional standards. Tesco supplies full dimension tables for each pressure rating.

Q5. What pressure ratings are available for plate flanges?

Plate flanges are available in EN/DIN ratings PN2.5, PN6, PN10, PN16, PN25, PN40, PN63/PN64 and PN100, JIS ratings 5K to 63K, and ASME classes 150 through 9000 — covering PN1 to PN400 overall.

Q6. Where are plate flanges used?

Plate flanges are used in oil & gas, chemical processing, water and wastewater treatment, food & beverage and pharmaceutical piping — connecting pipes, valves, pumps, heat exchangers and other equipment in low-to-moderate pressure systems.

Q7. How is a plate flange attached to the pipe?

A plate flange is slipped over the pipe end and secured with fillet welds — typically one external and one internal fillet weld — so the flat plate seats square to the pipe axis and the bolt holes straddle the centreline. The flat face mates against a gasket and the bolted flange of the adjoining equipment.

Q8. Are plate flanges supplied with material test certificates?

Yes. Every plate flange is supplied with EN 10204 3.1 (or 3.2) mill test certificates with heat/lot traceability, dimensional inspection, and PMI and third-party inspection on request.

Q9. Can plate flanges be used as backing flanges for HDPE or GRP pipe?

Yes — this is one of their biggest modern uses. A loose plate flange slides over the plastic or GRP stub end (collar) and provides the steel bolting ring the joint needs, while the stub's face does the sealing — the same principle as a lap joint. Galvanized carbon steel backing rings are the water-industry default on HDPE lines; stainless is used in coastal and chemical duty. State the stub-end standard and collar OD when ordering so the bore and any back-face radius are machined to suit.

Q10. How much does a plate flange weigh?

The least of any flange type — there is no hub. As working approximations for carbon steel PN 16 plate flanges: DN50 about 1.5 kg, DN100 about 3.5 kg, DN200 about 8 kg and DN300 about 16 kg, with galvanizing adding a few percent. Stainless weighs essentially the same. Every quotation states the exact unit weight for the pattern and rating ordered.

Q11. Are plate flanges cut from plate or forged?

Cut from certified plate — that is the type's identity and the source of its economy: rings are profiled from IS 2062, A516 or stainless plate, then machined and drilled, with the plate heat's mill certificate carried through to the flange. Forged construction is available on request where a project specification insists on forgings, but for the low-pressure water, HVAC and backing duties plate flanges serve, plate-cut construction is the accepted industry norm.

Q12. Can plate flanges be galvanized?

Yes — hot-dip galvanizing is the standard finish for water supply, fire-fighting and structural service, and plate flanges take it well because there are no threads or gasket-critical machined grooves to protect. Flanges are dispatched galvanized to IS 4759 / ISO 1461 with faces usable as-coated, or supplied bare for painting. Epoxy and FBE coatings are also available for buried and marine duty.

Q13. What details are needed to get an accurate plate flange quotation?

Five elements plus commercial terms: (1) size and pattern — e.g. DN150 EN 1092-1 Type 01, DIN 2576 or BS 10 Table E; (2) PN rating or table letter; (3) facing — flat face or raised face; (4) duty — weld-on, or loose backing flange with the collar OD stated; (5) material grade and finish — e.g. IS 2062 galvanized, A516 Gr.70, SS 316L — with EN 10204 3.1 or 3.2 certification stated. Add the quantity and destination and we return price, weight and delivery — normally within 24 hours.

Q14. Who manufactures plate flanges in India?

Tesco Steel & Engineering is an ISO 9001:2015 certified flange manufacturer based in Mumbai, India, producing plate flanges to EN 1092-1 Type 01, DIN 2573/2576, BS 10, BS 4504 and AS 2129 patterns in carbon steel, galvanized, stainless and duplex grades — welded-on or as backing flanges for HDPE and GRP systems. Flanges ship with EN 10204 3.1/3.2 certification and are exported to more than 50 countries.