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A Brief History of Flanges
Hydrotesting of Flanges
Stainless Steel Plate Flanges

Stainless Plate Products, Inc.

<<These plate flange reference tables detail outside and inside diameter sizes and bolt hole drilling pattens for various standard plate flanges.>>

Flanges - Commentary

SST Systems, Inc.

<<There are multiple questions regarding how flanges should be considered in computer-aided analyses. First, it is important to understand that flange failures do not result in pipe ruptures, rather a leak is often considered a flange "failure," especially if the contents are hazardous. A B31.1 Interpretation in the late 1990's sought to clarify this, and while there was general agreement to a statement that would suggest that flanges don't normally break, the Interpretation failed to be approved for publication because the B31.1 Code did not already say this in some manner.>>

Mack Iron Products

The Mack Iron Works Company

<<Conical, basket, flat, line and tank suction strainers, spectacle blinds, single blinds and ring spaces of all types, orifice plates and bleed rings. Metal fabrication company since 1901.>>

SPO Compact Flange

Vector International

<<The compact flange provides everything that a standard flange does not - space saving, reduced weight and, perhaps most importantly, a guaranteed leak-free connection. The reduced dimensions of the compact flange are achieved by reducing the seal diameter, which in turn, reduces the cross-section area of the seal faces. Second, the gasket is replaced by a sealring which works with the seal faces, not against them, to ensure face-toface mating, so that only low seating forces are required to compress the seal faces. With lower pressures needed, both the size and number of the bolts can be reduced, ultimately providing a smaller, lighter-weight connection (70-80 percent smaller and lighter than ANSI flanges in the case of Vector’s products).>>

Flange Data (Large PDF file, but worth the wait)

Texas Flange

<<ASME and Non code flanges for the Petrochemical, Process, Waterworks industries.>>

Flange Spreaders


Flange Identification


Flange Facing

Boltex Mfg. Co.

<<Types of flange facings, flange face finish>>

About Flanges

Boltex Mfg. Co.

Flange Leakage - Will it Ever Go Away?

Carmagen Engineering

<<Have you ever gotten the feeling that some problems never go away, or that you've solved the same problem once (or twice!) before? Flange leakage is one of those things that seem to fall into this category. In spite of all our efforts, completely curing flange leakage sometimes seems like a losing battle. But should it be? This series of articles will discuss this problem and some ways to solve it. Most of what will be discussed will not be a revelation to experienced plant engineers. However, writing down the seemingly obvious helps focus attention, increases general awareness, and helps solve the problem.>>

Description of Common Flange Types

Unit Operations Laboratory, Clemson University Chemical Engineering Department

<<Flanges are most often used to connect pipes that have a diameter greater than 2 inches. A flange joint consists of two matching disks of metal separated by a gasket that are bolted together to achieve a strong seal with the gasket material. The flange is attached to the pipe by welding, brazing, or screwed fittings. A number of the most common types of flanges are listed below.>>

What is an Insert Flange?

Stainless Insert Flange Company

<<Insert Flanges are a specialty in the arena of pipe size flanges and consist of two parts - the insert and the flange ring. The flange ring is the outer part of the insert flange assembly, containing the bolt holes. Except perhaps for the thickness, it is similar to the standard B16.5 flange beyond the raised face or gasket surface. It's function, along with the bolting, has but one major purpose, and that is to be the clamp that applies the necessary axial force against the insert to seat the gasket and to withstand the pressure and other piping forces and moments. Material selection is relatively simple, considering only atmospheric corrosion, strength, temperature and economy.>>

Safety Boy Flange Spreader

Newman Tools Inc.

DIN Flange Dimension Chart (in French - "Gabarit des Brides DIN")


What is a Flange?

Henning, Metz, Hartford and Associates, Inc.

<<There are basically eight (8) types of flanges - weldneck flanges, slip-on flanges, lap joint flanges, threaded flanges, socket weld flanges, reducing flanges, blind flanges and orifice flanges.>>

Flange Types - Selection and Application

Henning, Metz, Hartford and Associates, Inc.

Flange Faces - Types

Henning, Metz, Hartford and Associates, Inc.

How to Build a Reliable, Practically Leak-Free Thermal Fluid System

<<If you are concerned only with minimizing leaks, a properly designed and installed all-welded system will provide much better leak protection than a system with flanged and screwed connections. How-ever, the trade-off with an all-welded system is a decided lack of flexibility for maintenance operations. For example, while it is possible to repair or rebuild a valve inline, it is much easier and cheaper to remove the valve and send it out for repair. In practice, most thermal fluid systems contain a number of flanged and screwed connections and each is a potential leak point. For this reason (and for the sake of the system operators who will have to deal with any leaks), a thermal fluid system should be designed to include only as many breakable connections as are absolutely necessary.>>

Flange Types, Descriptions and Applications

Welding Units Inc.

<<A flange allows two pipes to be mechanically connected together, or a pipe to be mechanically connected to a valve, tee, choke or other piece of equipment. The principle of a flange is to use a mechanical force (exerted by the bolts) to pre-load the gasket sufficiently so that when internal pressure (end cap force) is applied, there is enough contact stress between the flanges and gasket to maintain a seal. The flange itself needs to be connected to the pipe. This is usually achieved by welding, though threaded and other weldless connections also exist. Types of flanges include WELDNECK, SLIP-ON, SOCKET WELD, LAP JOINT, THREADED, SWIVEL, BLIND, ORIFICE and ANCHOR/HANGER. All flanges are sized according to their nominal bore size. For the majority of pipe sizes, this designation does not represent either their actual outside diameter or inside diameter.>>

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ISSN 1496-3426
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