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