Welcome! Drafting 2323: Pipe Drafting Andrew Amini Full Time Instructor, HCC
Chapter 4-Flange Basics 1 Flange-ring shaped device that is an alternative to welding or threading components together. Flanges allows they are more economical, reliable, and have less leakage than large bore threaded pipe. Nozzle-the point where the piping configuration is connected to the equipment. The beginning of the pipe configuration is where the nozzle-flange configuration is at.
Chapter 2-Steel Pipe 2 Manufacturing Methods: Carbon steel pipe is manufactured based on pipe strength, wall thickness, corrosion resistance, temperature, and pressure Common manufacturing methods are for seamless, butt- welded, and spiral welded pipe Seamless Pipe-piercing a billet with a mandrel to produce a pipe that has no seams or joints Butt-welded Pipe-Feeding a hot steel plates through shapers to obtain a hollow circular shape. Spiral-Welded pipe-Formed by twisting strips of metal into a spiral shape
Chapter 4-Flange Ratings 3 Flanges and nozzles are sized according to ASME. The pressure ratings are the pound ratings. For steel flanges-150#, 300#, 400#, 600#, 900#, 1500#, 2500# Cast iron flanges-25#, 125#, 250#, 800# Common Relationship for P/T: As the temperature increases then the pressure rating will decrease
Chapter 4-Flange Facings 4 The mating surface for a flange, nozzle, or valve is called a face. Flat Face-Commonly in the 150#, 300# rating to make connections to the 125#, 250# cast iron flanges. Less cracking due to full surface contact.
Chapter 4-Flange Facings 5 Raised Face- Comes in 7 sizes (150#, 300#, 400#, 600#, 900#, 1500#, 2500#) 150#, 300# hav ea 1/16” raised face Flanges 400# and above have a ¼” raised face
Chapter 4-Flange Facings 6 Ring-Type Joint-does not use a gasket for a seal but instead forms the seal via the deep groove in the flange face. This is considered the best flange but has the high cost due to the internal pressure seal that is created.
Chapter 4-Flange Types 7 Weld neck flange- Its design is to reduce high stress at the base of the flange by transferring the stress to the adjoining pipe. This is used in High Pressure, High Temperature applications. Bore of the weld neck flange is the key in its design and its fitting to the pipe. ID of the weld neck flange and the ID of the pipe are matching.
Chapter 4-Flange Types 8 Lap-Joint Flange-used for carbon or low alloy steel piping systems. The lap joint flange and the stub end are used for frequent dismantling for inspection and routine maintenance
Chapter 4-Flange Types 9 Slip-On Flange-Allows the pipe to be inserted prior to welding. It is used in applications where there is limitations in space. The lifespan is much shorter and the cost is lower.
Chapter 4-Flange Types 10 Threaded Flange-This is a great option when welding can not be done on the flange. The threaded flange is not good in high temperature, high stress applied. At time a seal weld is added in order to prevent leakage.
Chapter 4-Flange Types 11 Socket-Weld Flange-Used for small piping systems in high pressure. The OD of the pipe is inserted into the ID of the socket weld then they are both welded. This creates a tight seal to prevent leakage
Chapter 4-Flange Types 12 Reducing Flange-used in the installation of a reduced diameter pipe. Flow should be from the reducing flange to the large OD. If flow were to go from the larger pipe to the reducing flange there would be severe turbulence.
Chapter 4-Flange Types 13 Blind Flange- Serves the purpose of a plug or cap to terminate the end of a piping system. The Blind Flange is bolted to form the seal
Chapter 4-Flange Types 14 Orifice Flange- Is to measure the rate of flow of commodity through the piping system. They have a hole drilled perpendicular to the direction of the pipe and they have a set of jack screws. It has two flanges, two gaskets, one plate, bolts, nuts, and jack screws. A valve tap is inserted to measure the flow
Chapter 4-Flange Types 15 Bolts- are critical since they must match the size of the flange to determine the size, spacing, and the number of bolts to be used. Bolt hole alignment is important for installation purposes. Formula: 360 degrees/ (# of holes)= Angular location of Bolts Bolts are available in machine or studs. Machine bolts have a head end and the rest is threads Stud are all threads that have two nuts to be installed.
Chapter 4-Flange Types 16 Gasket-is needed to have a leak proof seal between two metal surfaces. Gaskets are usually 1/8” size Full Face Gasket- Flat Ring Gasket- Metal Ring Gasket-