PIPE DRAFTING AND DESIGN THIRD EDITION EBOOK

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Pipe Drafting and Design - 3rd Edition - ISBN: , . View on ScienceDirect eBook ISBN: Paperback ISBN. Pipe Drafting and Design, Third Edition provides step-by-step instructions to walk pipe designers, drafters, and students through the creation of piping. Editorial Reviews. Review. "Parisher (engineering design graphics, San Jacinto College Pipe Drafting and Design 3rd Edition, site Edition. by.


Pipe Drafting And Design Third Edition Ebook

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Library of Congress Cataloging-in-Publication Data Parisher, Roy A. Pipe drafting and design / Roy A. Parisher, Robert A. Rhea-2nd ed. p. cm. Includes index. pipe drafting and design third abromishico.cf - Ebook download as PDF File .pdf), Text File .txt) or read book online. download Pipe Drafting and Design 3rd edition () by Roy A. Parisher for up to 90% off at abromishico.cf

The various molecular components of plastics make them susceptible to chemical reactions with certain compounds. Hazardous mixtures must be avoided. Pressure and temperature limitations must be established for obvious reasons. Pipe that is overheated or pressurized beyond capacity can rupture, split, or burst.

Stress, as applied to pipe, entails physical demands such as length of service, resistance to expansion and contraction, and fluctuations in pressure and temperature. Excessive stresses in the form of restricted expansion and contraction, and frequent or sudden changes in internal pressure and temperature must be avoided. Threading plastic pipe is not a viable option because it is expensive. Pipe 12" and smaller is typically drawn single line and pipe 14" and larger is drawn double line.

Single-line drawings are used to identify the centerline of the pipe. Double lines are used to represent the pipe's nominal size diameter. Typically hand drawn, single-line pipe is drawn with a. Double-line pipe uses standard line widths to draw the pipe's nominal size diameter. A centerline is used on all double pipe to allow for the placement of dimensions. Steel Pipe Figure provides several representations of pipe as it may appear on a drawing.

When pipe is represented on a drawing, typically the pipe's nominal size dimension is used to identify pipe size. There are certain applications, however, when the pipe's true outside diameter dimension is used to 11 represent the pipe on a drawing. Drawings created with most software packages are an example. Piping software programs draw with such accuracy that pipe is drawn using the actual outside diameter. Pipe created by means other than a piping software program in this text will be drawn using nominal sizes.

Be aware that drawings created with a piping software program use actual outside dimensions and will differ slightly from manual and AutoCAD generated drawings. Pipe representations. Name three methods of manufacturing carbon steel pipe. Name the three most commonly used end preparations for joining pipe.

What is meant by the term nominal size pipel 4. Which diameter of pipe varies as the wall thickness changes? What is the most common material used in the manufacture of pipe? When drawing pipe, which pipe sizes are drawn single line and which sizes are drawn double line? How long is the gap between two lengths of pipe when a back-up ring separates them? What is the name for the amount of pipe "lost" when screwed connections are used?

What is the standard drawing scale used on piping drawings? Name three-methods for joining carbon steel and plastic pipe. Pipe Fittings Fittings are fabricated pieces of pipe that are used to make changes of direction elbow , branch from a main pipe tee , or make a reduction in line size reducer see Figure Because fittings are part of the piping system, they must match as closely as possible in specification and rating to the pipe to which they are being attached.

Fittings, like pipe, are manufactured and classified according to their wall thickness. There are many more wall thicknesses of pipe however than there are thicknesses of fittings. Fittings are commercially manufactured in standard weight, extra strong, Schedule , and double extra strong.

In the petrochemical industry, most companies have guidelines known as piping specifications that state pipe 3" and larger will be fabricated with butt-welded connections. These specifications, or specs, as they are more commonly called, may also require pipe smaller than 3" to have screwed or socket-weld connections. For uniformity, the previously mentioned specifications will be used throughout this book as a basis for determining pipe connection requirements.

However, this is not to say this is the only spec that can be written. There may be cases where small bore pipe is butt-welded, while larger sizes may be screwed or socket-welded, oniuc tLBUWo Of all the fittings, the elbow is the one most often used. Simply put, the elbow, or ell, is used when a pipe changes direction. Elbows can turn up, turn down, turn Figure Ninety degree ells can be classified as one of the following: When determining the length of an elbow, one must establish the center-to-end dimension.

The center-to-end dimension is the measurement from the centerline of the fitting to the end of the fitting see Figure Notice the relationship between the nominal size and the length of the fitting. The fitting's length is equal to the nominal pipe size plus one-half of the nominal size. A simple formula in the next column makes calculating this dimension easy to remember. Long radius elbow. Use this formula for butt-weld fittings only. Long-Radius Elbow Dimensional sizes of fittings are typically provided by the manufacturer of the fitting.

Manufacturers issue dimensioning charts containing lengths for a particular fitting. The dimensional charts used to establish sizes of fittings discussed in this text are listed on the Welded Fittings-Flanges Chart provided in Appendix A.

As a reference, portions of that chart are used throughout this chapter when fitting measurements are needed. The measurement labeled A represents the center-to-end length of the fitting.

To find the fitting's length in inches, locate the appropriate nominal pipe size Figure Center-to-end dimension of a long-radius elbow. Welded Fittings-Flanges Chart.

Pipe Fittings 15 in the row labeled Nominal Pipe Sizes. Follow across the chart to find the desired pipe size. The center-to-end dimension A will be used as the radius for the elbow's centerline. Remember, in the single-line symbol only the centerline of the elbow is drawn. The double-line symbol requires that one-half of the pipe OD should be added and subtracted respectively from the elbow's centerline.

To better visualize the long-radius elbow, we have attached a piece of pipe to each end of the fitting. Figure shows the steps using manual drafting techniques and Figure shows those steps using AutoCAD commands. Manual drafting solutions. Step 1. Mark off the distance from the center of the fitting to the end of the fitting.

Step 3. Extend the ends of the fitting down and across respectively until they intersect. This will be the centerpoint for drawing the arcs that will form the ell. Use a circle tern- Step 2. Determine the nominal size of pipe and mark off one-half of its size on each side of the fitting's centerline. Remember, for fittings 12" and below, only the arc representing the elbow's centerline is drawn when creating single-line symbols.

AutoCAD commands. Drawing set-up. The 21" radius should be measured above PT. Step 2. The offset distance will be equal to one-half of the. Step 4. Use the LINE command to draw the ends of elbow.

The step-by-step instructional procedures presented using computer-aided drafting techniques presume each student has a comprehensive knowledge of basic AutoCAD commands. These self-instructional steps provide a simple method to create each fitting. They are not intended to restrict the student to any particular commands. Each student is encouraged to experiment with new commands that may achieve the same result.

Conversely, the short-radius ell also creates a rather large pressure drop inside the line and does not have the smooth flow characteristics the longradius ell has. For these reasons the short-radius ell is seldom used.

Center-to-end dimension of the shortradius elbow. Whenever a short-radius ell is used, the abbreviated note S. The mitered elbow is not an actual fitting, but instead is a manufactured turn in the piping system. This elbow is made by making angular cuts in a straight run of pipe and then welding the cuts together after they have been rolled to a different angle see Figure The mitered ell may be classified as one, two, three, or four weld miters.

The number of welds used depends on the smoothness of flow required through the turn. A twoweld miter will create more turbulence within the pipe than will a four-weld miter. Long-radius and short radius elbows. Drafting Symbols for Mitered Elbows Figure shows the double-line drafting symbols for two-weld and three-weld mitered elbows.

Unlike the previous ells, the weld lines in the adjacent views of the mitered elbow are represented by ellipses. Ellipses are used because the welds are not perpendicular to your line of sight.

Therefore, when projecting from the front view to any of the four adjoining views, the welds must be drawn elliptical in shape. Short-radius elbow symbols Figure Mitered elbows. Pipe Fittings 19 Figure Miter elbows drafting symbols. This elbow is also used to make changes in direction within the piping system. Figures and describe two manual methods for constructing the elbow. Figure defines steps using AutoCAD commands to draw the elbow.

Pipe Fittings 21 Figure Alternative manual solution. Determine one-half of the pipe's diameter and mark Step 2. This will P'P Step 4. Use a circle template to draw the inside and outside arcs representing the elbow. Draw an arc to represent the elbow's centerline. ERASE the two construction lines. Use LINE to draw the two ends of the elbow. In some orthographic views, these elbows will appear at an angle to our line of sight.

In those views where the open end of the elbow appears at an angle to our line of sight, ellipses must be used to represent the end of the fittings. It is a three-way fitting used to make perpendicular connections to a pipe see Figure Lines that connect to the main run of pipe are known as branches.

The main run of pipe is often called the header. Figure shows a pipe header with two branch connections. Drafting Symbols for the Weld Tee Notice that the weld tee requires three welds be made to install the fitting. Two types of tees are used in the piping industry: Figure shows the drawing symbols for straight and reducing tees. A callout is required on the reducing tee to identify the header and branch sizes.

The header size is shown first. Pipe Fittings Figure Weld tee. Header and branch connections. Weld tee symbols. Pipe Fittings 25 Figure From the center of the tee, draw a perpendicular line, either up or down, depending on the direction of the branch, Step 2. Measure 7" one-half the header pipe size on either side of the centerline to draw the sides of the tee. Measure 7" one-half the branch pipe size on either side of the perpendicular line to draw the branch of the tee.

Draw and darken the sides and weld lines of the tee. Add break symbols. ZOOM, Extents. These dimensions are required to determine the center-to-end length of the header and the length of the branch end. If a straight tee is being used, the C dimension found on the Welded Fittings-Flanges Chart in Figure must be added twice to find the total length of the fitting. On a straight tee, the C dimension is also used as the length of the branch end. If a reducing tee is being drawn, the M dimension must be substituted as the length of the branch end.

Figures and provide the manual and AutoCAD steps for drawing the tee. Another method of making a branch connection is called a stub-in. The stub-in is most commonly used as an alternative to the reducing tee.

The stub-in is not an actual fitting but rather a description of how the branch connection is created. A hole is bored into the header pipe, either the size of the OD or ID of the branch, and the branch is then stubbed into it. The two pipes are fitted together and then welded. Although the branch connection can be the same pipe size or smaller as the header, it cannot be larger.

Figure depicts the attachment of a stub-in. Figure provides the single-line and double-line drawing symbols for a stub-in. Stub-in connections. Stub-in symbols. Pipe Fittings How close stub-ins are made is an important consideration. A general rule is to allow a minimum of 3" between welds. This means a minimum of 3" should be allowed between the outsides of branches made from a common header, and a header should be attached no closer than 3" to a fitting.

Figure provides the minimum measurements allowed between branches and fittings on an 18" header. Stub-in Reinforcements Even though the use of the stub-in is limited by the pressure, temperature, and commodity within a pipe, its use is becoming increasingly more popular. Its chief advantage over the tee is cost. Not only can the cost of downloading a fitting be avoided, but the stub-in requires only one weld; whereas, the tee requires three. Three remforcmg alternat. Resembling a metal washer that , 0 ,been.

Qr, K f f ,, has bent. T plate ,. It is slipped onto the branch pipe then welded to both branch and header. A downloadd reinforcing pad, the welding saddle has a short neck designed to give additional support to the branch.

Figure shows 27 drawing representations of reinforcing pads and saddles. downloadd fittings, o-lets have one end shaped to the contour of the header and the other end manufactured to accept the type of end connections being used on the branch. Weldolets are manufactured for butt-weld fittings. Sockolets are made for socket-weld fittings. And threadolets are available for screwed fittings. Figure shows a typical threadolet. Figure gives drawing symbols for weldolets, sockolets, and threadolets.

Figure shows a latrolet and the elbolet. There are two common methods M used to make branch connections with couplings: The coupling rests on the external surface of the pipe header and is welded from the outside.

A hole is bored into the pipe header large enough to accept the OD of the coupling. The coupling is inserted into the hole and is then welded. Figure shows the coupling in use. Welding minimums for stub-ins.

Reinforcing pads and saddles. Latrolet and elbolet. Appropriately named, the reducer is available in two styles as shown in Figure Concentric—having a common centerline. Eccentric—having offset centerlines. The concentric reducer maintains the same centerline at both the large and small ends of the fitting. The eccentric reducer has offset centerlines that will maintain a flat side on the top or the bottom of the fitting, depending on how the fitting is rolled prior to welding.

The eccentric reducer is used in piperacks to maintain a constant bottom of pipe BOP. Because pipe supports within a piperack are of the same elevation, a pipe must have a consistent bottom of pipe elevation so it can rest on each support throughout its entire length. Using a concentric reducer in a piperack would not permit the small diameter end of the pipe run to rest on a pipe support. Eccentric reducers are also used on pump suction nozzles to keep entrained air from entering the pump.

By keeping a flat on top FOT surface, vapor pockets can be eliminated. It is important that a designer not forget to include the dimensional difference between the two centerlines of an Pipe Fittings 29 Figure Couplings as branches.

Eccentric and concentric reducer. A quicker, though less accurate method, is to take onehalf the difference between the two outside diameters. Drawing the Reducers Drafting Symbols for the Concentric and Eccentric Reducer The orthographic views for the concentric and eccentric reducers are shown in Figure No matter the size of the reducer, it is always drawn as a double-line symbol.

Notice the callouts that must be included with the eccentric reducer. The large end is always listed first, no matter the direction of flow, and the flat side must be indicated. Prior to drawing the reducer, the length of the fitting must be found on the Welded Fittings-Flanges Chart see Figure The H dimension will provide the end-toend length for either the concentric or eccentric reducer.

Always use the H dimension of the large end to determine the fitting length. Figures and provide the manual and AutoCAD steps for drawing the reducer. Eccentric reducers. Concentric and eccentric drawing symbols. Using the H dimension found on the chart, draw a centerline 14" long. Connect the opposite ends of the fitting by drawing lines from endpoint to endpoint.

Measure 8" one-half the large end size on either side of the centerline on one end and 7" on either side of the centerline on the opposite end. Darken the sides and weld lines of the reducer, Pipe Fittings 31 Figure ZOOM, All.

pipe drafting and design third edition.pdf

Place note as required. The last weld fitting we will discuss is the weld cap. It Welding one fitting directly to another is called fittingis used to seal an open end of pipe. When dimensioning make-up see the examples in Figure The cap will be system require the designer to use pipe of various lengths welded to the end and need not be included in the length between the fittings. In these cases, pipe is cut to the dimension of the run of pipe.

When fittings are not assemble-line symbol for all sizes of pipe. By maintaining this to construct the round end of the fitting. Notice the weld dot on the single line see Rgure 3. We will now look at how each fitting relates to other fittings when used in the design of various piping systems.

Welds may seem insignificant to the designer, but, it goes without saying, a piping facility could not be built without them. Remember, all welds must be shown on drawings. Use weld dots on single-line pipe symbols and weld lines on double-line pipe symbols.

At the present time, we are only concerned with butt-weld fittings. The general rules-of-thumb for placing dimensions on a drawing are as follows: Pipe should be dimensioned from center of fitting to the end of pipe Figure provides some examples for placing dimensions on drawings.

3rd Edition

Weld cap drawing symbols. Fitting make-up. Minimum pipe lengths. There are, however, a few differences that must be examined. Screwed and socket-weld fittings are normally reserved for installations using fittings 3" and smaller. Screwed and socketweld fittings are also available in cast iron, malleable iron, or forged steel. Cast iron and malleable iron fittings are typically used on low pressure and temperature lines such as air, water, or condensate.

Lines containing high pressure and temperature commodities, which are subject to movement and vibration, require fittings made of forged steel. Forged steel screwed and socket-weld fittings are manufactured in two pressure classes— and Dimensional charts for screwed and socket-weld fittings are provided in Appendix A. These dimensioning charts supply measurements for and fittings.

Figures and provide a sample of the dimension charts for screwed and socket-weld fittings found in Appendix A. Most screwed fittings are manufactured with internal, female threads per American Standard and API thread guidelines see Figure Some fittings, such as plugs and swages, however, are manufactured with external threads. The socket-weld fitting is replacing the screwed fitting as the choice of many fabricators because it offers greater strength.

Even though screwed fittings can be seal welded if necessary, strength of the fitting is decreased when the threads are cut during the manufacturing process. Socket-weld fittings can be easily fitted and welded without the need of special clamps or tackwelds, which are often required to hold a butt-weld fitting in place before the final weld is made see Figure Like butt-weld fittings, screwed and socket-weld fittings are used to make similar configurations in a piping system.

Screwed and socket-weld fittings differ in size and shape, but they achieve the same purpose as the buttweld fittings. Figure provides examples of some screwed and socket-weld fittings. Screwed and socket-weld fittings are drawn with square corners using short hash marks to represent the ends of the fitting see Figure Manufactured for screwed and socket-weld applications, the union is represented on drawings as shown in Figure Unions should be positioned in locations that will facilitate the easy removal of critical pieces of equipment.

Figure shows how unions are placed in a configuration to allow easy removal of the valves. Plug The plug, like a cap, is designed to close off the end of a run of pipe. Plugs are manufactured for screwed fittings with male threads and are screwed into the end of a pipe to create a seal. Figure shows the drawing symbols for the plug. Coupling Although this fitting is used in butt-welding applications as a branch connection, its primary use is to connect lengths of screwed and socket-weld pipe together.

Some clients may stipulate, however, that all socket-weld pipe must be connected with a butt weld, rather than a coupling.

Screwed fittings are manufactured with threads on the inside of the fitting, and socket-weld fittings have an internal socket that prevents fitting makeup assembly. To facilitate the assembly of screwed and socket-weld fittings, small lengths of pipe called pipe nipples are used between fittings. Pipe nipples can vary in length depending upon the distance required to fabricate the pipe configuration. A close nipple is one that provides the minimum length of pipe between fittings.

Remember, screwed and socket-weld fittings have a certain amount of lost pipe due to thread engagement and socket depth. Therefore, each size pipe has a different minimum length for the dimension of a close nipple. Many companies will use 3" as the standard minimum for pipe nipples. This length will accommodate the amount of pipe lost inside the fitting on each end as well as provide sufficient wrench clearance during assembly for the larger screwed and socket-weld pipe sizes.

Placement of dimensions. Screwed fittings dimensioning chart. Socket-weld fittings dimensioning chart. Internal and external threads.

A.MSTERDAM • BOSTON • HEIDELBERG • LONOON

Socket-weld fittings. Screwed and socket-weld fittings. Swage One exception to the standard 3" minimum rule is the swage nipple. Swages are functionally similar to reducers, but are specifically designed for screwed and socketweld pipe.

Screwed swages have male external threads and can be connected to other screwed fittings without the use of a pipe nipple.

They are used to make reductions in the line size on a straight run of pipe. Swages, like reducers, are available in either a concentric or eccentric shape. Figure shows varying lengths and sizes of screwed pipe and swage nipples.

Screwed and socket-weld drawing symbols. Pipe Fittings 37 Figure Union Figure Positioning of unions. Union drawing symbols. Swages are unique in that they can be used in screwed, socket-weld, or butt-weld configurations. When used in these configurations, swages will have different end preparations. Screwed swages will have thread ends TE , socket-weld swages plain ends PE , and butt-weld swages have beveled ends BE.

Because socket-weld swages are inserted into mating fittings, many companies allow the substitution of beveled-end swages. Dual purpose fittings like these will make the job of the downloading group much easier. Swages are also manufactured with different preparations on the two ends.

When specifying a swage, use the following abbreviations: Plug drawing symbols. Notice the end preparation combinations on the examples. Figure shows the drawing symbols for swages. The major difference is their method of connection. The connection joint for flanged fittings is made by bolting two specially designed metal surfaces together.

A gasket to prevent leaks is sandwiched between the two surfaces. Flange types will be discussed at great length in the following chapter. Pipe and swage nipples. Swage drawing symbols. Concentric swages. Because molten cast iron can be easily manufactured into many unique shapes that cannot be attained with steel, manufacturers use it to produce fittings with many varying turns, bends, and branches.

The physical appearance of pipe routing configurations made of cast iron fittings is quite different from pipe routed with forged steel fittings because of the large assortment of fittings available and the method in which these configurations are assembled.

Above-ground Plastic fittings can also be manufactured in many diverse and unique shapes. All the standard fitting shapes are available: Plastic fittings are manufactured for either screwed, socket, or butted assembly. Plastic screwed and socket fittings are available in sizes through 4" in diameter.

Butt fittings are manufactured for sizes 6"". Typically, pipe smaller than 3" in diameter is manufactured as having end connections. What is the most common fitting used? What are the four classifications of elbows? What is the formula for calculating the center-to-end dimension for LR and SR elbows? Describe a mitered elbow. When configuring tee connections, what is the main run of pipe called? Name the two types of tees. What are some alternate methods to a tee fitting when fabricating branch connections?

Which fitting is used to make a reduction in the line size of a run of pipe? Name the two types of reducers. Define fitting make-up. What are the two pressure classifications for screwed and socket-weld fittings?

What type of fittings must be bolted together? What is the typical installation service for cast iron pipe? Name the three types of plastic fitting end types manufactured. To complete the exercises, draw the symbols below using the following guidelines. DO NOT include text with the blocked symbol. Insert the required symbols into the appropriate locations.

The pipe break symbol is created with ellipses. The ma or axis of each J ellipse is equal to one-half of the P1? AutoCAD drawing symbols and File names. They are , , , , , , and Cast iron flanges have pound ratings of 25 , , , and Pound ratings, when combined with the temperature of the commodity within the pipe, are used to select the appropriate size, rating, and type of flange.

When temperature decreases the allowable pressure increases, and vice versa. Pound ratings are also used to establish the outside diameter and thickness of a flange. Typically as pound ratings increase, so will the flange's diameter and thickness. The flange is a ring-shaped device designed to be used as an alternative to welding or threading various piping system components used throughout the piping system. Flanged connections are used as an alternative to welding because they can be easily disassembled for shipping, routine inspection, maintenance, or replacement.

When drawing pipe, which pipe sizes are drawn single line and which sizes are drawn double line? How long is the gap between two lengths of pipe when a back-up ring separates them?

What is the name for the amount of pipe "lost" when screwed connections are used? What is the standard drawing scale used on piping drawings? Name three-methods for joining carbon steel and plastic pipe. Pipe Fittings Fittings are fabricated pieces of pipe that are used to make changes of direction elbow , branch from a main pipe tee , or make a reduction in line size reducer see Figure Because fittings are part of the piping system, they must match as closely as possible in specification and rating to the pipe to which they are being attached.

Fittings, like pipe, are manufactured and classified according to their wall thickness. There are many more wall thicknesses of pipe however than there are thicknesses of fittings. Fittings are commercially manufactured in standard weight, extra strong, Schedule , and double extra strong. In the petrochemical industry, most companies have guidelines known as piping specifications that state pipe 3" and larger will be fabricated with butt-welded connections.

These specifications, or specs, as they are more commonly called, may also require pipe smaller than 3" to have screwed or socket-weld connections. For uniformity, the previously mentioned specifications will be used throughout this book as a basis for determining pipe connection requirements.

However, this is not to say this is the only spec that can be written. There may be cases where small bore pipe is butt-welded, while larger sizes may be screwed or socket-welded, oniuc tLBUWo Of all the fittings, the elbow is the one most often used. Simply put, the elbow, or ell, is used when a pipe changes direction. Elbows can turn up, turn down, turn Figure When determining the length of an elbow, one must establish the center-to-end dimension. The center-to-end dimension is the measurement from the centerline of the fitting to the end of the fitting see Figure Notice the relationship between the nominal size and the length of the fitting.

The fitting's length is equal to the nominal pipe size plus one-half of the nominal size. A simple formula in the next column makes calculating this dimension easy to remember. Long radius elbow. Long-Radius Elbow Dimensional sizes of fittings are typically provided by the manufacturer of the fitting.

Manufacturers issue dimensioning charts containing lengths for a particular fitting. The dimensional charts used to establish sizes of fittings discussed in this text are listed on the Welded Fittings-Flanges Chart provided in Appendix A.

As a reference, portions of that chart are used throughout this chapter when fitting measurements are needed. The measurement labeled A represents the center-to-end length of the fitting. To find the fitting's length in inches, locate the appropriate nominal pipe size Figure Center-to-end dimension of a long-radius elbow.

Welded Fittings-Flanges Chart. Pipe Fittings 15 in the row labeled Nominal Pipe Sizes. Follow across the chart to find the desired pipe size. The center-to-end dimension A will be used as the radius for the elbow's centerline. Remember, in the single-line symbol only the centerline of the elbow is drawn.

Pipe drafting and design

The double-line symbol requires that one-half of the pipe OD should be added and subtracted respectively from the elbow's centerline. To better visualize the long-radius elbow, we have attached a piece of pipe to each end of the fitting. Figure shows the steps using manual drafting techniques and Figure shows those steps using AutoCAD commands.

Manual drafting solutions. Step 1. Mark off the distance from the center of the fitting to the end of the fitting. Step 3. Extend the ends of the fitting down and across respectively until they intersect. This will be the centerpoint for drawing the arcs that will form the ell. Use a circle tern- Step 2.

Determine the nominal size of pipe and mark off one-half of its size on each side of the fitting's centerline. Remember, for fittings 12" and below, only the arc representing the elbow's centerline is drawn when creating single-line symbols.

AutoCAD commands. Drawing set-up. The 21" radius should be measured above PT. Step 2. The offset distance will be equal to one-half of the. Step 4. Use the LINE command to draw the ends of elbow. Pipe Fittings 11 NOTE: The step-by-step instructional procedures presented using computer-aided drafting techniques presume each student has a comprehensive knowledge of basic AutoCAD commands.

These self-instructional steps provide a simple method to create each fitting. They are not intended to restrict the student to any particular commands. Each student is encouraged to experiment with new commands that may achieve the same result. Conversely, the short-radius ell also creates a rather large pressure drop inside the line and does not have the smooth flow characteristics the longradius ell has. Pipe designers and drafters. Overview of Pipe Drafting and Design 2. Steel Pipe 3. Pipe Fittings 4.

Flange Basics 5. Valves 6. Mechanical Equipment 7. Flow Diagrams and Instrumentation 8. Codes and Specifications 9. Equipment Layout Piping Arrangement Drawings, Sections, and Elevations Standard Piping Details Piping Systems Piping Isometrics Building 3D Piping Models Project Coordination. Appendix A. Dimensional Data B. Alphabet of Lines C. Review of Math D. Use of the Calculator E.

Has several years of industrial experience in piping design with Fluor and Litwin.This feature makes the threaded flange well-suited to extreme pressure services that operate at normal atmospheric temperatures and in highly explosive areas where welding may create a hazard.

Unfortunately, you will be liable for any costs incurred in return to sender parcels if the information you provided was inaccurate. Elbows can turn up, turn down, turn Figure Start by pressing the button below! Pressure and temperature limitations must be established for obvious reasons. Pipe drafting and design, third edition Author: Pipe Drafting and Design, Third Edition provides step-by-step instructions to walk pipe designers, drafters, and students through the creation of piping arrangement and isometric drawings.

And threadolets are available for screwed fittings. These valves can be adjusted and regulated to pop off-when internal pressures exceed predetermined settings.

It includes instructions for the proper drawing of symbols for fittings, flanges, valves, and mechanical equipment.