Flanges and Pipe Fittings

Rio Manufacturers of Stainless Steel,Carbon Steel and Nickel Alloys Flanges, Buttweld Fittings and Forge Fittings of different shapes and sizes and with different specifications as per the customers’ requirement. Rio is the world leader in Forged Flanges and Buttweld Fittings. We cater to the huge global demand of our customers who are spread across 6 continents and around 90 countries. Rio flanges are reputed and well known across the globe for their reliability and quality. At Rio, we treat our customers as our partners by providing them with our products and solutions. And this ethos is displayed in not only our thoughts but also in our actions.

Our flanges division encompasses an integrated forge shop which manufacturers all types of pipe fittings i.e. flanges, butt welding fittings in various specifications (ASME/ ANSI, EN, DIN, AFNOR, AWWA, GOST, BS, JIS, AS, MSS, SA, UNI etc) as well as forged bars.

We produce flanges in the size range from ½” to 40”. Rio has an established and stringent quality system with more than 90 approvals and certifications in accordance with various specific requirements and applications. These approvals and certifications help us supply Rio Flanges to major end users across a diverse list of industries.

Applications of Flanges and Pipe Fittings
  • Pipeline engineering
  • Oil & gas industry
  • Mechanical engineering
  • Plant engineering
  • Marine industry
  • Waste water management
  • Chemical industry
  • Petrochemical industry
  • Power industry
  • Aerospace
  • Food processing industry and many more.

Our integrated facilities include facilities for cutting, forging, ring rolling and machines with CNC lathes, CNC drilling, high capacity forging press and mobile manipulator for making big diameter forged round bars. We also have an in-house heat treatment shop and well equipped laboratory facilities for ensuring the quality of our products.

Types of Flanges - Our manufacturing facilities is well equipped to manufacture various types of flanges namely:

  • Blind Flange- A Blind flange is round plate which has all of the relevant boltholes but no centre hole, and because of this feature this flange is used to close off the ends of a piping systems and pressure vessel openings. It also permits easy access to vessels or Piping systems for inspection purposes.
  • Weld Neck Flange- Weld Neck Flanges have a long tapered hub and are often used for high pressure applications. These flanges are designed to be joined to a Piping system by Bun Welding. The Neck, or Hub, transmits stresses to the Pipe, reducing stress concentrations at the base of the Flange. The gradual transition of thickness from the base of the Hub to the wall thickness at the Bun Weld, provides important reinforcement of the Flange. The bore of the Flange matches the bore of the Pipe, reducing turbulence and erosion. These flanges are ideal for extreme fluctuations of temperature and in environments where there may be high pressure or high temperature being dealt with.
  • Slip-on Flange- These are easily fitted and welded into different pipes. Slip on pipe flange is slipped over the Pipe and then welded both inside and outside to provide sufficient strength and prevent leakage. These flanges are ideal for lower pressure applications. This Flange is used in preference to Weld Necks by many users because of its lower cost and the fact that less accuracy is required when cutting pipe to length.
  • Socket Weld Flange- These flanges are attached by inserting the pipe into the socket end. This allows for a smooth bore and better flow of the fluid or gas inside of the pipe. Socket-weld pipe flanges are mainly used for smaller sizes of high pressure pipes.
  • Threaded Flange- Threaded flanges are similar to slip-on pipe flanges except the bore of threaded pipe flange has tapered threads. These flanges are ideal for relatively low pressure piping systems. Threaded flanges are used with pipes that have external threads. The benefit of these pipe flanges is that it can be attached without welding.
  • Lap Joint Flange- Lap Joint Flanges slide over the pipe and are most commonly used with Stub End Fittings. A pipe is typically welded to the Stub End and the Lap Joint pipe flange is free to rotate around the stub end. Lap Joint pipe flanges are often used for applications that require frequent dismantling. Threaded pipe flanges are often used for small diameter, high pressure requirements.
  • Orifice Flange- Orifice Flanges are used instead of standard pipe flanges when an orifice plate or flow nozzle must be installed. Pairs of pressure tappings are machined into the orifice flange, making seperate orifice carriers or tappings in the pipe wall nexessary.

In addition to these we also manufacture Orifice Flange, Stub-end fittings, plate flanges, backup flanges, Beveled ID flanges and Reducing flanges.

Our Manufacturing Capacity: 5,000 MT per annum
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Flanges & Pipe Fittings

Blind Flang

We Rio Engineering are Manufacturers and Exporters of Blind Flanges…

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Weld Neck Flang

Long welding neck flanges (“LWN”) are similar to weld neck…

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Socket Weld Flang

Socket Weld flanges were initially developed for use on small-size…

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Rio Engineering is from Mumbai, Maharashtra ensures that each…

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Stock Finish serration, Spiral or Phonographic Serration, Concentric Serration, Smooth Finish


  • Raw Material Cutting: Band Saw
  • Open/Close Die Forging & Rolling: Hammer/Press/Ring Rolling
  • Machining :CNC Lathes/SPM Lathes
  • Bolt Hole Drilling: High Speed CNC Vertical Machining Center
  • Heat Treatment: Solution Annealing (Batch Annealing Furnaces)