Welcome to our journey for all piping community.., On this moment, we'll learn together what is meaning of piping design..??!! step by step we could learn from the basic to advance level for piping design. And please made a difference between piping design and analysis. so.., here we come....

Basic of Pipe

Piping systems are like arteries and veins. They carry the lifeblood of moderncivilization. In a modern city they transport water from the sources of water supplyto the points of distribution; convey waste from residential and commercial buildingsand other civic facilities to the treatment facility or the point of discharge. Similarly,pipelines carry crude oil from oil wells to tank farms for storage or to refineriesfor processing. The natural gas transportation and distribution lines convey naturalgas from the source and storage tank forms to points of utilization, such as powerplants, industrial facilities, and commercial and residential communities. In chemicalplants, paper mills, food processing plants, and other similar industrial establishments,the piping systems are utilized to carry liquids, chemicals, mixtures, gases,vapors, and solids from one location to another.The fire protection piping networks in residential, commercial, industrial, andother buildings carry fire suppression fluids, such as water, gases, and chemicals toprovide protection of life and property. The piping systems in thermal power plantsconvey high-pressure and high-temperature steam to generate electricity. Otherpiping systems in a power plant transport high- and low-pressure water, chemicals,low-pressure steam, and condensate. Sophisticated piping systems are used to processand carry hazardous and toxic substances. The storm and wastewater pipingsystems transport large quantities of water away from towns, cities, and industrialand similar establishments to safeguard life, property, and essential facilities.In health facilities, piping systems are used to transport gases and fluids formedical purposes. The piping systems in laboratories carry gases, chemicals, vapors,and other fluids that are critical for conducting research and development. In short,the piping systems are an essential and integral part of our modern civilization justas arteries and veins are essential to the human body.The design, construction, operation, and maintenance of various piping systemsinvolve understanding of piping fundamentals, materials, generic and specific designconsiderations, fabrication and installation, examinations, and testing and inspectionrequirements, in addition to the local, state and federal regulations.Piping includes pipe, flanges, fittings, bolting, gaskets, valves, and the pressurecontainingportions of other piping components. It also includes pipe hangers andsupports and other items necessary to prevent overpressurization and overstressingof the pressure-containing components. It is evident that pipe is one element or apart of piping. Therefore, pipe sections when joined with fittings, valves, and othermechanical equipment and properly supported by hangers and supports, are called piping.

INTRODUCTION OF FITTING STANDARDS & PIPING CONNECTION

 A piping route is made up of variety of connection elements that called ‘Fittings’. The major piping materials are also produced in the form of standard fittings. Among the more widely used materials are ductile or cast iron, malleable iron, brass, copper, cast steel, forged steel, and wrought steel. Other major nonferrous piping materials are also produced in the form of cast and wrought fittings. 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 160, and double extra strong or by rating.
As generally fitting consist of ( 2 ) two types :
1. Wrought fitting
Base on ANSI B16.9 standard, its shall be in accordance with ASTM A 234, A 403, A 420, A 815, B 361, B 363, B 366, or the corresponding standard listed in Section II of the ASME Boiler and Pressure Vessel Code. The term wrought denotes fittings made of pipe, tubing, plate, or forgings. Fittings made from block forgings may only be supplied subject to agreement between the manufacturer and purchaser.
1.a Applied
Mostly to be used for above 2” NPS pipe.
1.b End Preparation
Unless otherwise specified, the details of the welding end preparation shall be in accordance with ASME B16.25 (see below pictures)

1.c Components for Wrought Fitting
There are several components for wrought fitting that usually used on pipe route and consist of :

Most commonly has 5 ( five ) types :
1. 45˚ elbow
2. 90˚ long radius elbow, r = 1.5xNPS
3. 90˚ short radius elbow, r = 1xNPS
4. Return bend elbow
5. 90˚ reducer elbow
Some others specification have different visual or unusual form (see the pictures below)


Standard mentioned on bill of material chart,

When to applied
If the condition piping route want to change direction 45 degree or 90 degree. The standard Butt-Weld elbows ( 90°, 45° and 180° ) can be altered to meet any special angle needs of a piping system. Elbows like pipe can be flame cut or machine cut to the required angle. The rough end is then ground or machine beveled to the proper angle for welding. There is normally no harm to the fitting when this is done. In this case for elbow 3D or 5D commonly used when the flow process become powder materials and the other thing for unusual elbow 90 which is commonly for high pressure system with pressure range 7500 – 15000 Psi thats called ‘target block elbow” ( base on case at jack-up process unit ).Some other cases or standard have the own way to change flow direction with bending pipe.


Most commonly has 2 ( two ) types :
1. Reducing tee
2. Straight tee
Standard mentioned on bill of material chart,

When to applied
If the condition piping route want to give branch as well as same with run pipe or reduce, so we should put ‘the Tee’. But we could made the branch from spool pipe as per standard that regulate for it. The dimensions of Tees are not as simple as they are for Ells. For Tees you must look them up on a fitting chart. The dimension found there is however standardized between all manufacturers. For Straight Tees the center-to-end dimension of both ends and for the branch outlet is the same. For Reducing Tees the center-to-end of the branch outlet is different from that of the run

c. Reducer or Increaser

Most generally has 2 ( two ) types :
1. Concentric reducer
2. Eccentric reducer
Standard mentioned on bill of material chart,

When to applied
Eccentric or concentric reducer, basicly to reduce pipe routing from bigger to the smaller size but eccentric reducer mostly used when avoid cavitation and to maintain elevation BOP (bottom of pipe) in rack. Some other case no need reducer when change pipe to the smaller size, cause of the swaging process apply it. The dimensions for reducers must be looked up but are normally standardized among the manufacturers for a given size. The length of a reducer is the same for a range of sizes (Example: The end-to-end dimension for 10" x 4", 10" x 6" and 10" x 8" reducers is 7"). As you can see the length of a Reducer is very short in relation to the diameter.

 d. End cap


Standard mentioned on bill of material chart,

When to applied
End cap mostly used when we need plug off end of pipe cause no need to continued the process. Weld caps are most often found at the bottom of a piping configuration called a "Boot." A boot is a short length of pipe with a pipe Cap that is attached to the bottom of steam line and provides for the collection of condensate. Caps should never be stored in a position to trap rain water or sand. Some other case just fabricate the plate to plug off and thats called ‘end plug’.

e. Weldolet

Standard mentioned on bill of material chart,

When to applied
Weldolet is used for butt weld branch connection where standard tee is not available due to size restrictions and the piping is of critical / high pressure service. Applicable with working temperature above 800 ˚F and mostly used on sch 160 or XXS for the branches.

f. Cross, Straight or Reducing
Straight crosses are usually stock items and reducing crosses may not be readily available. For the economic, availability and to minimize the number of items in inventory, it is preferred to use tees, etc., and not crosses, except where space is restricted, as in marine piping or ‘revamp’ work. Reinforcement is not needed.

g. Lateral, Straight or Reducing

Permits odd-angled entry into the pipe run where low resistance to flow is important. Straight laterals with branch bore equal to run bore are available in STD and XS weights. Reducing laterals and laterals at angles other than 45 degrees are usually are available only to special order. Reinforcement is required when it is necessary to restore the strength of the joint to the full strength of the pipe. Reducing laterals are ordered similarly to butt-weld tees, except that the angle between branch and run is also stated

2. Forged Fitting
Base on ANSI B16.11 standard, forged steel screwed and socketweld fittings become one of fittings in ANSI systems. These fittings perform the same function as the Butt-Weld fittings. There function is the same but the method of joining and the dimensioning is different. Normally these fittings are used in sizes 1-1/2" (or 2") and smaller. Welded fittings are specified the same as the pipe, by weight, schedule or wall thickness. Screwed and Socket-Weld fittings are specified per the pressure class. Thread engagements as well as the depths of the sockets for different pipe sizes are different and must be looked-up on an approved dimension table. These fittings are used for steam, water, oil, gas, and air. They are available in 2,000, 3,000 and 6,000-1b classes.
2.a Threaded Fitting For Pressure Classes
• 125# Cast Iron
• 250# Cast Iron
• 300# Malleable Iron
• 2000# Forged Steel *
• 3000# Forged Steel *
• 6000# Forged Steel
( * most common )

The Cast Iron and Malleable Iron fittings are basically used for air and water services at a low temperature and pressure. Forged fittings are normally used for higher pressures and temperatures as well as for the more complex commodities. The majority of the screwed fittings will have female (internal) threads per NPT (National Pipe Thread). The exception will be the swages and the plugs - they will have male (external) threads.

2.b Socket-Weld Fittings are Manufactured in Two Classes
• 3000# Forged Steel
• 6000# Forged Steel
Socket-Weld fittings have a deep socket into which the pipe slips and aligns itself. The weld is then made on the outer surface of the pipe and fitting. This eliminate the need for or use of special clamps or tack welding for alignment prior to the final fit-up welding. At the bottom of the socket a 1/16" gap is left to compensate for expansion when the weld is made. This gap is called a root-gap. The swage does not have an internal socket; it will fit into the socket of a fitting or be butt-welded to a pipe.

2.c Common Screwed and Socket-Weld Fittings

there are 2 (two) types :
1. 45˚ elbow ( threaded or socket-weld )
2. 90˚ elbow ( threaded or socket-weld )



there are 2 (two) types :
1. straight tee ( threaded or socket-weld )
2. reducing tee ( threaded or socket-weld )

c. Union
The Union is basically used as a dismantling fitting, and in many cases it is necessary for assembly. The field crew may install extra Unions at their own discretion to expedite and facilitate the construction of socket-weld and screwed piping.


there are 2 (two) types :
1. Socket-weld union
2. threaded union

d. Reducer


there are 2 (two) types :
1. Reducer insert
2. Coupling reducer

3. Piping Connection Alternative
There are a few alternates to the normal methods of doing business discussed above
We talked about elbows as a way to change direction. You can change direction without using elbows. You might do this with a Miter Ell (or Mitre, both spellings are correct). A Miter Ell is where no fitting is used. Miters are normally used in large size/low pressure piping. You fabricate the Miter or change in direction from pipe segments (or pieces) that are cut at specific angles depending on the number of pieces and welds required. This is really effective when really odd angles are required. Two of the pieces are the incoming pipe and the out-going pipe. There may be no middle piece or there may be one (or more) other short middle pieces depending on the angle of the turn. A simple turn of 45° might be made with a two-piece/one weld miter. Other changes in direction might be three piece/two weld miters, three piece/two weld miters and so on. The number of welds is always one less than the number of pieces. Depending on the size and schedule of the pipe a Miter might be cheaper than buying fittings. In small diameter piping the miter is more expensive (labor costs) and there is more pressure drop through a small miter than a small fitting. Miters are also not recommended for high temperature lines because miters are more susceptible to overstressing.

b. Stub-in or Stub-on

We talked about using Straight Tees and Reducing Tees as a way to make branches from a line. For low pressure (or reasonably low pressure) there is another way to make branches from a line. This method uses only pipe. It is normally used only for low pressure/low temperature applications where the branch is reducing. The ASME B31.3 (and other piping B31 Code sections) recognize two basic versions of the pipe to pipe branch. One method is where the run pipe has a hole cut the outside diameter of the branch pipe. This opening is then beveled for a "full penetration weld" The branch pipe is saddle cut (with no bevel) to match the I. D. of the run pipe. They are then fitted together and welded. The second method is where the diameter of the hole in the run pipe is the same I. D. as the I. D. of the branch pipe. This hole does not get a bevel. The end of the branch pipe is saddle cut to fit the run pipe and is then beveled for a full penetration weld. With the first method, the branch pipe is inserted in the run pipe. With the second method, the branch pipe is set on the run pipe. Both are still commonly referred to as "Stub-ins" Both of these can come non-reinforced (as described above) or reinforced. The reinforced version is normally only required for higher stress situations. The reinforcement is a "ring" plate cut from some scrape run pipe or the same material as the run pipe. At the center is a hole the same size as the branch pipe. If cut from flat plate it is then shaped to fit around the run pipe. The width of the ring is normally one half the diameter of the branch pipe. The ring is intended to replace the material that was removed when the hole was cut in the run pipe. A small diameter hole (1/4" NPT) is normally drilled (and tapped) in the ring to act as a vent during the welding process and to allow for Hydrotesting of the welds. The ring is then welded to the branch pipe and the run pipe with full penetration welds. The small hole is fitted with a plug after work is completed.
Which one is preferred ? For branching of one size lesser of run pipe, stub-on is preferred. For other branching less than one size of run pipe stub-in is preferred. The design is based on ANSI B31.3.