fittings - seabird groups€¢ asme b16.9 covers overall dimensions, tolerances, ratings, testing...
Post on 15-Jun-2018
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• The major piping materials are also produced in
the form of standard fittings.
• Fittings may be made to special dimensions, sizes,
shapes, and tolerances by agreement between the
manufacturer and the purchaser.
FITTING – Introduction
Continued...
Why we need Fittings ???
Fitting Produce change in geometry and include:
1. Change in direction of piping
FITTING – Introduction
Continued...
Fitting produce change in geometry and include:
2. Alter pipe diameter
FITTING – Introduction
Continued...
Fitting produce change in geometry and include:
3. Terminate pipe
FITTING – Introduction
Continued...
Fitting produce change in geometry and include:
4. Bring pipes together (made branch from main pipe run)
FITTING – Introduction
• Each fitting shall be permanently marked to show the following
• Manufacturer’s name or trademark
• Material identification, either the ASTM or ASME grade designation
• Schedule number or nominal wall thickness in mm
• Size - the nominal pipe size (NPS) identification number related to the end connections shall be used
FITTING –Standard Marking
• ASME B16.9 covers Overall Dimensions, Tolerances, Ratings, Testing & Marking for wrought factory made butt welding fittings
• Materials:
– For carbon steel fittings, refer ASTM A234
– For Austenitic stainless steel, refer ASTM A403
– For Alloy steel, refer ASTM A420
• Used in most piping systems NPS ≥ 2, rarely from NPS ½
• Difficult to weld in small sizes, especially for thin wall
BUTT WELD FITTINGS
• Installed between two lengths of pipe or tubing to allow a change of direction, usually a 90° or 45°
• Based on Curvature ( 90 °),
– Short radius (1 NPS)
– Long radius (1 ½ NPS)
– Extra Long radius (3 NPS)
• Size Specification:
EX: 90° LR Elbow 6” Sch. 40
BUTT WELD FITTINGS – Elbow
Continued...
• Reducing elbow:
– Available in 90°
– Curvature = 1 ½ NPS of larger end)
• Size Specification:
EX: 90° LR Red. Elbow 6”x4” Sch. 40
BUTT WELD FITTINGS – Elbow
Continued...
• Bend:
– Used to change the direction of run of pipe
– Common Center line (Curvature) = 4 - 6 NPS
– Made from seamless and ERW straight pipe
– Two methods used to making bend
Hot
Cold
• Size Specification:
EX: 90° Bend 8” Sch. 40
BUTT WELD FITTINGS – Bend
Continued...21
• The function of a return bend is to change direction of flow through 180°
• Long radius (1 ½ NPS) and short radius (1 NPS)
• Both types have a centre to centre dimension double the matching 90° elbows.
• Size Specification:
EX: 180° LR Return 10” Sch. 40
• The primary application for these fittings is in • Heater coils
• Heat exchangers
• Boilers
• Vent on tanks etc
BUTT WELD FITTINGS – Return
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• Joint made by beveling each of two parts to be joined, usually at a 45° angle (Site Fabrication)
• 2 Piece (pressure drop ≈ 4-6 times of Long Radius elbow)
• 3 Piece (pressure drop ≈ 2 times of Long Radius elbow)
• Used in
• Low pressure line
• Pressure drop not important
• NPS > 10”
BUTT WELD FITTINGS – Miter
• A reducer allows for a change in pipe size to meet hydraulic flow requirements (Increase in pressure) of the system
• To adapt to existing piping of a different size
• Types:
• Concentric
• Eccentric
Continued...
BUTT WELD FITTINGS – Reducer
30
• Types:
1 Concentric
• Both inlet and outlet ends are on a common centre line
• Easier and less expensive to produce
• Size Specification:
EX: CR 3” x 1½ ” Sch 10s
Continued...
BUTT WELD FITTINGS – Reducer
31
• Types:
2 Eccentric
• Two sides having offset centre lines
• Eccentric reducers are used when required to maintain the same top- or bottom-of-pipe level.
• Where we need Support under piping
• Size Specification:
EX: ER 3” x 1½ ” Sch 10s
Continued...
BUTT WELD FITTINGS – Reducer
32
Eccentric Reducer used in suction of pump
Continued...
BUTT WELD FITTINGS – Reducer
34
Suction from Bottom Side
Suction from Top Side
BUTT WELD FITTINGS – ReducerStandard Reducer Dimensions (from ASME B16.9)
36
For remaining sizes refer ASME B16.9
• It is a type of pipe fitting which is T-shaped having two outlets at 90° to the connection to the main line
• The function of a tee is to permit flow at 90° to the main direction of flow.
• The main flow passes through the ‘run’ whilst the 90°outlet is known as the ‘branch’.
• A tee is used for connecting pipes of same/ different diameters or for changing the direction of pipe runs
BUTT WELD FITTINGS – Tee
Continued...
• Equal Tee: Branch is same as header pipes.
• Size specification:
– EQ. TEE 4” x 4” Sch. 40
BUTT WELD FITTINGS – Tee
Unequal Tee:
• Run and Branches are in different diameter.
• To obtain the desired flow and pressure through the system.
• Types:
• Reducing Tee
• Bullhead tee
BUTT WELD FITTINGS – Tee
Bullhead tee:
• Branch larger than run & rarely used and made to special order
• Size Specification: Red TEE 4” x 4” x 6”, Sch. 40
BUTT WELD FITTINGS – Tee
• If a branch line passes completely through a tee, the fitting becomes a cross
• A cross has one inlet and three outlets, or vice versa
• Cross fittings are also called 4-way fittings
• Cross fittings can generate a huge amount of stress on pipe as temperature changes, because they are at the center of four connection points.
• A tee is more steady than a cross
• Size Specification:
EQ. Cross 6” Sch. 40
BUTT WELD FITTINGS – Cross
Continued...
Types:
– Straight/ Equal Cross:
– Reducing Cross:
1 Straight/ Equal Cross: All four outlets of equal size
BUTT WELD FITTINGS – Cross
Continued...
Reducing Cross:
Branches that are smaller in size to obtain the desired flow and pressure through the system (rarely used)
BUTT WELD FITTINGS – Cross
Continued...
BUTT WELD FITTINGS – CrossReducing Outlet Tee/ Cross Dimensions (From ASME B16.9)
Continued...
For remaining sizes refer ASME B16.9
• Forged or Site fabricated fitting
• Size Specification:
– Run inlet × run outlet × branch × angle respect to outlet
Lat. Tee 6”×6”×4”×45° Sch 40
45
BUTT WELD FITTINGS – Lateral
Continued...
• A type of pipe fitting, usually liquid or gas tight, whichcovers the end of a pipe
• If a cap is used to provide for a future connectionpoint, several inches of pipe must be left before thecap. This is because when the cap is cut off for thefuture connection, enough pipe must remain to allowa new fitting to be connected onto it
– Cap– Flat closure
BUTT WELD FITTINGS – Closure
Continued...
• Connect butt-welded piping to smaller socket-weld or screwed
• Abrupt change of line size
• Type:
• Venturi: Allows smoother flow
• Eccentric
• Concentric
BUTT WELD FITTINGS – Swage
Continued...
• Stub ends are installed in pairs and mated together with two lap joint flanges
• The surface of the stub end has a serrated gasket surface which prevents leakage at the joint.
• Using stub ends allows sections of the line to be opened for cleaning, inspection or quick replacement etc., without the need to re-weld.
BUTT WELD FITTINGS – Lap Joint Stub Ends
BUTT WELD FITTINGS – Backing Ring
• The backing ring is placed in between the ends of two pipes to secure a joint.
• It is then welded so that the material is melted and fused with pipes.
• When used properly, it prevents the weld metal from penetrating through the pipes.
• This transforms the two pipes and the backing ring into one single pipe.
• Whenever branch connections are required in size where
reducing tees are not available
• When the branch connections are of smaller size as
compared to header size
EX: Taking 2” branch from 20” pipe
• Basically self reinforced fittings (no RF pad required)
OLETS
• Generally types of Olets:
– Weldolet
– Sockolet
– Elbowlet
– Thredolet
– Latrolet
– Nipolet
– Swepolet
– Flanged Olet (Nipoflange)
OLETS
OLETS – Sockolet
• Sockolet is used for Socket weld branch connection
• Generally used to take drain and vent connection from big size pipe
• Elbolet used for taking reducing tangent branch on elbows
• Branch connection is Butt weld
OLETS – Elbolet
• Latrolet : Used for taking reducing branch connection at 45°
• Branch connection is Butt weld
• Generally used to connect safety relief valve outlets with common header pipe.
OLETS – Laterolet
• Sweepolet
– Good flow pattern and optimum stress distribution
– 90° reducing from the main pipe
OLETS – Sweepolet
• It looks like Weldolet/ Nipolet welded with a weld neck flange
• Flaged Olet is used for Flanged branch connection
OLETS – Flanged Olet (NipoFlange)
• Size frequently limited to NPS ≤ 1 ½”
• ASME B16.11: This Standard covers ratings, dimensions, tolerances, marking and material requirements for forged fittings, both socket-welding and threaded
• Materials:
– For forged Carbon Steel, Refer ASTM A105
– For forged alloy steel and stainless steel, Refer ASTM A182
– For Wrought Carbon Steel, Refer ASTM A234
SOCKET WELD FITTINGS
• Not used in “Severe Cyclic Conditions” and in services where corrosion is accelerated in crevices
• No weld metal can enter bore, easier alignment on small line than butt-weld
• Have not any leakage
SOCKET WELD FITTINGS
• A coupling connects two pipes to each other.
Types:
• Full coupling
• Half Coupling
SOCKET WELD FITTINGS – Coupling
Half coupling
• Half-couplings have Socket at one end. The other end is welded or otherwise fastened to the piping/ tubing.
• Normally used in hose connections
SOCKET WELD FITTINGS – Coupling
SOCKET WELD FITTINGS – Reducer
Coupling with one end Smaller Diameter used to connect different size pipes
• Swage :
– Abrupt change of line size in Socket Weld
– Swage Nipple welded with Coupling
SOCKET WELD FITTINGS – Swage
Socket Fitting
Swage
• Union is similar to a coupling, except it is designed to allow quick and convenient disconnection of pipes for maintenance or fixture replacement
SOCKET WELD FITTINGS – Union
• Common materials
– For Gray iron, refer ASME B16.4
– For Malleable iron, refer ASME B16.3
– For Steel, refer ASME B16.11
• Threaded joints are normally used in low-pressure small-bore, non-flammable service
• Threaded joints up to NPS 12 (DN300) have been used in low-pressure liquid service.
• Generally not used where leaks cannot be tolerated
THREADED/ SCREWED FITTINGS
Half coupling
• Half-couplings is threaded at one end. The other end is welded or otherwise fastened to the piping/ tubing.
• Normally used in hose connections
THREADED FITTINGS – Coupling
Threaded Half Coupling
• A tee is the most common pipe fitting.
• It is available with all female thread sockets, rarely with male thread
THREADED FITTINGS – Tee
THREADED FITTINGS – Hexagon Bushing
Used to connect Instruments having threaded ends such as Pressure/ Temperature gauges
• Threaded Elbolet
• Threaded Latrolet
• Threaded Nippolet
THREADED FITTINGS – ‘O’ let
Threaded
Connections
• Closure
– Cap
– Plug: A plug closes off the end of a pipe. It is similar to a cap but it fits inside the matted fitting
THREADED FITTINGS – Closure
• Nipple is a fitting, consisting of a short piece of pipe, usually provided with a male pipe thread at each end, for connecting two other fittings.
THREADED FITTINGS – Nipple
FITTINGS - Materials
• Materials used
– Ductile or cast iron, Malleable iron, Brass, Copper, Cast steel, Forged steel, Wrought steel.
• The term wrought denotes fittings made of pipe, tubing, plate, or forgings
Continued...
ASME B16.1 Cast Iron Pipe Flanges and FlangedFittings, Class 25, 125, 250, and 800 (Thestandard also includes bolt, nut, andgasket data.)
ASME B16.4 Gray Iron Threaded Fittings, Class 125and 250
ASME B16.12 Cast Iron Threaded Drainage Fitting
Cast-iron fittings are covered by a number of ASME
FITTINGS - Materials
Continued...116
ANSI/AWWA C110/A21.10
Ductile Iron and Gray Iron Fittings, 3-inthrough 48-in (76 mm through 1200 mm),for Water and Other Liquids
ANSI/AWWA C115/A21.15
Ductile Iron and Gray Iron Fittings, 3-inthrough 48-in (76 mm through 1200 mm),for Water
ANSI/AWWA C153/A21.53
Ductile Iron Compact Fittings, 3-in through24-in (76 mm through 610 mm) and 54-inthrough 64-in (1400 mm through 1600 mm),for Water Service.
FITTINGS - Materials
Ductile Iron fittings are covered by a number of ANSI/AWWA standards:
117
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