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Lap join stub end

Lap Joint Stub Ends are normally provided with a standard weld bevel. Lap Joint Stub Ends are fittings used in place of welded flanges where rotating back up flanges are desired. A rotating back up flange seats itself against the back surface of the Stub End.

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Category:

Description

Lap joint stub end is a fitting that is used replace welded flanges when the support of a rotating back up flange is required. And It can be supplied in standard and non-standard ANSI dimension that is used for connecting pipes of different diameter.

Lap Joint Stub End Features

Lap joint stub end must have high quality, and it posses features as below:

  • Thermal stability
  • Long function life
  • High mechanical strength

Stub End Types

Stub end are offered in three different ways, type A, B and C. Type A and B stub end are similar to forged fittings, such as elbows and tees, and type C stub end are made in customized sizes.

Type A

The type A stub end is used for standard lap joint flange. The lap thickness on the stub end is greater than or equal to the nominal thickness of pipe wall. In addition, the outer corner radius of the type A can receive the lap joint flange. The inside corner is square. Lap usually has a machined serrated face.

Type B

The type B stub end is used for standard slip on flanges as lap flanges. The lap thickness on these short ends is greater than or equal to the nominal thickness of pipe wall. Also, the outer corner radius of type B is small enough to receive the slip o flange that can be used as a backup flange. The inner corner is square. Lap usually has a machined serrated face.

Type C

The type C stub end can be used for standard lap joint flange and slip on flange. It is flared leaving a rounded edge at the inside diameter of the lap. If necessary, the radius can be made closed to a square. The lap thickness is 75% of the pipe wall. The type C is very short enough to accommodate any backup flange. The lap joint on type C is smooth, and it is not machine.

Common Types and Lengths

Stub ends are usually manufactured in two ways, Type A and Type B. They are available in two standard length, long (ANSI) or short pattern (MSS).

Schedule 5s and 10s stub end are usually offered in short lengths, and long lengths are available on special order. Schedule 40s stub end are supplied in either short or long lengths.

Stub End Benefits

a. Easy to prepare(does not require cut faces to be parallel or perfectly flat)
b. Can be formed between two dissimilar metals, such as aluminum and copper.
c. Accommodates different thickness (thinner piece must be welded on top), thin material such as diaphragms and foils can be connected

Industrial Applications

Stub end is widely used in the petroleum, chemical, power, gas, metallurgy, shipbuilding and construction industries. It is made from high quality raw materials, and available in a variety of sizes and designs.

Stub ends are buttweld fittings that can be used (in combination with a lap joint flange) alternatively to welding neck flanges to make flanged connections.

Our Supply Range

  • Size range: 1/2” to 36”
  • Grade: ASME/ASTM SA A234
  • Type: Long and short lap joint stub ends
  • Wall Thickness: Schedule 5s, 10s, 20s, Sch10, Sch20, Sch30, STD, Sch40 and etc.
  • Manufacturing standard of stub end: ASME/ANSI B16.9, ASME B16.28, MSS-SP-43

Material:

  • Duplex
  • Carbon steel.
  • Alloy steel
  • Cupro Nickel
  • Low temperature steel
  • Stainless steel: 316/316L stainless steel, 304/304L stainless steel and chrome-moly
Nominal Pipe Size1/2 up to 2.1/23 to 3.1/24
Outside Diameter at Welding End (OD)0.80.80.8
Overall Length (F)1.61.61.6
Outside Diameter of Lap (G)000
-0.76-0.76-0.76
Thickness of Lap (T)1.521.521.52
000
Fillet Radius of Lap (R)000
-0.76-0.76-1.6
Wall Thickness (t)Not less than 87.5% of Nominal Wall Thickness
Dimensional tolerances are in millimeters unless otherwise indicated.

Stub ends dimensions

Nominal Pipe SizeOutside Diameter at BevelLengthRadius of FilletDiameter of Lap
NPSODLABD
NPSDLRG
1/221.35130.835
3/426.75130.843
133.45130.851
1 1/442.25150.864
1 1/248.35160.873
260.36480.892
2 1/2736480.8106
388.964100.8127
3 1/2101.676100.8140
4114.376110.8157
5141.376111.6185
6168.389131.6218
8219.1102131.6270
10273127131.6324
12323.8152131.6381
14355.6152131.6413
16406.4152131.6470
18457152131.6533
20508152131.6584
2255915213--641
24610152131.6692
The chart shows the MSS and ANSI stub end dimensions in inches.

The Stub End is available with us in different specifications, which find applications in a piping system to allow quick disconnection of the particular section involved.

Stub End is the fitting that be used in place of welded flanges where rotating back up flanges are desired.

MSS Type A stub ends are the industry norm and are utilized with standard flat face lap joint flanges. The lap thickness of the stub end typically meets the thickness of the schedule pipe it accompanies, and the exterior of the base has a curved machine radius for the lap joint flange to mate flush over the stub end. There are many instances in which lead time is critical and of more importance than adherence to existing ANSI / ASME flange specifications, and as such our customers will often choose to purchase a slip on flange and have the face machined to meet the radius requirement of the corresponding stub end piece.

ROC R16.9 2 1/2″ SCH 40S
A403 WPS304L

Dimensional tolerances of stub ends MSS SP-43

The MSS standard is the regular length stub end and the most commonly used in the flange industry.

Stubend geometry

Stubend geometry

N.D.Out diamaterHight(F)翻边直径G倒角半径R
NPSDNODMssANSINominal&maxNominal&minA MaxB Max
1/21521.350.876.2353430.8
3/42026.750.876.2434230.8
12533.450.8101.6515030.8
1 1/43242.450.8101.664634.80.8
1 1/24048.350.8101.673726.40.8
25060.363.5152.492917.90.8
2 1/2657363.5152.41051047.90.8
38088.963.5152.41271269.60.8
3 1/290101.676.2152.41401399.60.8
4100114.376.2152.415715611.20.8
5125141.376.2203.218618511.21.6
6150168.388.9203.221621512.71.6
8200219.1101.6203.227026912.71.6
10250273.112725432432212.71.6
12300323.9152.425438137912.71.6
14350355.6152.4304.841341112.71.6
16400406.4152.4304.847046812.71.6
18450457.2152.4304.853353112.71.6
20500508152.4304.858458212.71.6
22550559152.4304.864163912.71.6
24600610152.4304.869269012.71.6
The Stub End, which essentially a short length of pipe, which has one end that is flared outwards and the other end prepared to be welded to pipe of the same Nominal Pipe Size (NPS), material and of a similar wall thickness. The Lap Joint Flange, which is a ring backing Flange and it is very similar in geometry to the Slip-on Flange.

Stub ends are mechanical joints that comprises of two components.

This type of flanged connection was also referred to as “Van Stone” or “Vanstone flare laps”, however this is an historic terminology and very rarely used technically or commercially.

We offer stub ends at highly competitive prices.

Lap Joint Stub End – The ‘mated’ pair to a Lap Joint Flange. Stub Ends are Fittings used in place of welded flanges where rotating back up flanges are desired. Stub Ends are typically manufactured by two methods, Type A & Type B and are available in two standard lengths , long (ANSI) or short (MSS) pattern.

Features:

  • Thermal stability
  • High mechanical strength
  • Long functional life

Manufacturing standards of stub end:

  • ASTM ASME A/SA 403
  • MSS SP43 & SP75 ANSI B16. 9
  • ANSI B16. 28 ASTM A815 ASTM B363 B366
  • DIN2605 DIN2615 DIN2616 DIN2617
  • GB12459GB13401
  • JIS2313

Specifications:

  • Grades: ASME / ASTM SA / A234
  • Material:
  • Stainless Steel,316/316L Stainless Steel, 304/304L Stainless Steel and Chrome-moly
  • Carbon steel
Technical Specifications:
  • Thicknesses are based on ASME B16.48 specifications or the products can be manufactured to customer specifications.
  • Standard surface finish is 125-250 RMS serrated finish.
  • Other finishes available upon request.
  • c/w a standard shop primer on carbon steel products for rust inhibitor purposes.
  • Size: Available in all sizes and thickness

 

Lap-joint flanges are most commonly available in carbon steel and low temperature carbon steel, because it is a lower cost than the Stub End that will be wetted by the service and it must be of a suitable grade of steel. If orientation and alignment of bolt holes is the only issue, then for standardization, then the Stub End and the Lap Joint Flange can be of the same material.

The most common material grade for stub end is the ASTM A403 / ASME SA403 (stainless steel stub ends). With reference to EU materials, the most common grades are DIN 1.4301, DIN1.4306, DIN 1.4401, DIN 1.4404.

Stub Ends assemblyStub Ends assembly

Stub ends and lap joint flanges can be assembled following this process:

  • The Lap Flange is slipped over and onto the Stub end Flange.
  • The Stub End Flange is then welded onto a pipe spool, using an approved Welding. Procedure Specification (WPS), by a qualified Welder. The Lap Joint Flange, backing Flange, can revolve around the Stub End, which is now attached to the piping spool.
  • The bolt holes of the Lap Joint Flange can now be orientated and aligned with the bolt holes of a mating Flange of the same ASME designate rating and NPS.
  • The Lap Joint Flange can be mated to any Flange covered in ASME B16.5, Weld Neck, Slip On, Threaded, Socket Weld, another Lap Joint Flange.

It can also be mated to a fabricated plate Flange with compatible, bolting dimensions.

Why use Stub Ends

This means that instead of:

Duplex Stub End and a Duplex Lap Joint, you could have Duplex Stub End and Carbon Steel Lap Flange.

Or you could have Stainless Stub End and Carbon Steel Lap Flange. There are other bimetallic combinations that result in a flange assembly that is commercially cheaper.

During recent years the price differential between Duplex/Stainless Steel and Carbon Steel has narrowed and this practice on large Projects has become less common, however a cost difference always exists (the higher the NPS and the length of the pipeline / piping system, the higher the saving). On the other hand, the warehousing cost of one single component, i.e. a Weld Neck Flange, requires less shelf space than the cost of warehousing a Lap Joint and a Stub End. End Users and Contractors shall determine the actual convenience of using stub ends, considering all these factors and generally the commercial advantage is still valid and it may suit certain situation, especially in “brownfield” modifications.

How to order a Stub Ends

The following information shall be provided to order a stub end:

  • NPS
  • Schedule
  • Length (according to norms MSS SP43 / ASME B16.9 / custom)
  • Specs and material grade
  • Ends finish
  • Execution: seamless / welded (wx)

Stub end finish

Stub ends can be ordered with different ends finishing:

  • Beveled Ends
  • Squared Ends
  • Flanged Ends
  • Grooved Ends
  • Threaded Ends (Male Only)

Types

Stub end are offered in three different ways, type A, B and C. Type A and B stub end are similar to forged fittings, such as elbows and tees, and type C stub end are made in customized sizes.

Stub ends are manufactured in three different types and two standard length.

Type “A”: this type is produced and machined to fit lap joint flanges.The mating surfaces of the stub end and the lap joint flange have a matching profile and surface. The lap thickness of type A stub ends is > = the minimum wall thickness of the connected pipe. The outside the stub end and the lap joint flange have a matching profile and surface. The lap thickness of type A stub ends is > = the minimum wall thickness of the connected pipe. The outside corner of type A has a radius to accommodate the lap join flange, whereas the inside corner is squared.

Type “B”: this type of stub ends is suited for standard slip-on flanges acting as lap-joint flanges. The lap thickness of type B stub ends is >= the minimum WT of the connecting pipe. The lap of these type of stub ends has generally a serrated face. To ensure tight joints, chamfers on the ID side of the flange are required.

Type “C”: this last type can be used both with lap joint and slip-on backing flanges and are fabricated out of pipes. The lap of C-type stub ends is flared over and the lap thickness is 75% of the connecting pipe WT. Type C has a short fillet outer radius able to host any back up flange.

Type “CS”: this type is similar to “C” with the difference that the lap face has concentric serrations machined during the manufacturing process.

Common Types and Lengths

Stub ends are usually manufactured in two ways, Type A and Type B. They are available in two standard length, long (ANSI) or short pattern (MSS).
Schedule 5s and 10s stub end are usually offered in short lengths, and long lengths are available on special order. Schedule 40s stub end are supplied in either short or long lengths.

Short / long pattern stub ends (ASA/MSS)

Short pattern (MSS) and long pattern stub ends (ASA)

Stub ends are available in two different patterns:

  • the short pattern, called MSS-A stub ends
  • the long pattern, called ASA-A stub ends (or ANSI length stub end)

Stub ends dimensions and weight

Dimensions and manufacturing tolerances are covered in ASME B16.9 – Butt Weld Fittings and MSS-SP-43 (JIS B2312, JIS B2313 may also apply).

Stub End come in three standard lengths, MSS SP43 or ANSI B16.9 short and long pattern. Short pattern stub ends are mostly used for flanges from class 300 to class 600 and above. Besides these standard types, End-Users and contractors can require stub ends with non-standard lengths to suit specific project’s requirement. This will of course come at an additional cost.

Ends/Face lap finishing

ASME B16.25 END WELDING BEVEL as right

The following types of ends may be ordered:

Beveled Ends (generally ASME B16.25)
Squared Ends
Flanged Ends
Victaulic Grooves
Threaded Ends (Male Only)

Material for stub ends

Stub Ends are available in numerous ASTM and other international recognized materials, to match pipe specifications, as low alloy, stainless steel, austenitic-ferritic, high alloy steels (nickel alloy such as Inconel, Incoloy 800, Monel, Hastelloy C276), non-ferrous materials (copper, cupronickel 90 /10 and cupronickel 70 / 30) and titanium / zirconium / tantalum.
MaterialGradeUNS Equivalent
A234 WPB Carbon SteelBK03006
A403 Stainless Steel304/304LS30403
304HS30409
316/316LS31603
316HS31609
317LS31703
904LN08904
309S/HS30908
310SS31008
321S32100
6XNN08367
20CBN08020
347S34709
254SMOS31254
A815 Duplex /Super Duplex2205S31803/S32205
Zeron 100S32760
2507S32750
410S41000
A366 Nickel AlloysHC22N06022
HB-3N10675
HG3N06985
HXN06002
HC2000N06200
HC276N10276
NCIN06600
NCN04400
NN02200
NLN02201
NCMCN06625
NICMCN08825
NIC10N08810
NIC11N08811

Standard

Pipe fitting dimensions are in either metric or Standard English. Because pipe fitting covers Pipe Fitting Dimensions several aspects, only the most common pipe fitting sizes can be given here. The most applied version is the 90° long radius and the 45° elbow, while the 90° short radius elbow is applied if there is too little space. The function of a 180° elbow is to change direction of flow through 180°. Both, the LR and the SR types have a center to center dimension double the matching 90° elbows. These fittings will generally be used in furnesses or other heating or cooling units.

Some of the standards that apply to buttwelded fittings are listed below. Many organizations such as ASME, ASTM, ISO, MSS, etc. have very well developed standards and specifications for buttwelded fittings. It is always up to the designer to ensure that they are following the applicable standard and company specification, if available, during the design process.

Some widely used pipe fitting standards are as follows:

ASME: American Society for Mechanical Engineers
This is one of the reputed organizations in the world developing codes and standards.
The schedule number for pipe fitting starts from ASME/ANSI B16. The various classifications of ASME/ANSI B16 standards for different pipe fittings are as follows:

  • ASME/ANSI B16.1 – 1998 – Cast Iron Pipe Flanges and Flanged Fittings
  • ASME/ANSI B16.3 – 1998 – Malleable Iron Threaded Fittings
  • ASME/ANSI B16.4 – 1998 – Cast Iron Threaded Fittings
  • ASME/ANSI B16.5 – 1996 – Pipe Flanges and Flanged Fittings
  • ASME/ANSI B16.11 – 2001 – Forged Steel Fittings, Socket-Welding and Threaded
  • ASME/ANSI B16.14 – 1991 – Ferrous Pipe Plugs, Bushings and Locknuts with Pipe Threads
  • ASME/ANSI B16.15 – 1985 (R1994) – Cast Bronze Threaded Fittings
  • ASME/ANSI B16.25 – 1997 – Buttwelding Ends
  • ASME/ANSI B16.36 – 1996 – Orifice Flanges etc.

ASTM International: American Society for Testing and Materials
This is one of the largest voluntary standards development organizations in the world. It was originally known as the American Society for Testing and Materials (ASTM).

  • ASTM A105 / A105M – Specification for Carbon Steel Forgings for Piping Applications
  • ASTM A234 / A234M – Specification for Piping Fittings of Wrought Carbon Steel and Alloy Steel for Moderate and High Temperature Service
  • ASTM A403 / A403M – Specification for Wrought Austenitic Stainless Steel Piping Fittings
  • ASTM A420 / A420M – Standard Specification for Piping Fittings of Wrought Carbon Steel and Alloy Steel for Low-Temperature Service

AWWA: American Water Works Association

AWWA About – Established in 1881, the American Water Works Association is the largest nonprofit, scientific and educational association dedicated to managing and treating water, the world’s most important resource.

  • AWWA C110 – Ductile-Iron and Gray-Iron Fittings, 3 Inch Through 48 Inch (75 mm Through 1200 mm), for Water and Other Liquids
  • AWWA C208 – Dimensions for Fabricated Steel Water Pipe Fittings

ANSI: The American National Standards Institute

ANSI is a private, non-profit organization. Its main function is to administer and coordinate the U.S. voluntary standardization and conformity assessment system. It provides a forum for development of American national standards. ANSI assigns “schedule numbers”. These numbers classify wall thicknesses for different pressure uses.

MSS STANDARDS: Manufacturers Standardization Society
The Manufacturers Standardization Society (MSS) of the Valve and Fittings Industry is a non-profit technical association organized for development and improvement of industry, national and international codes and standards for: Valves, Valve Actuators, Valve Modification, Pipe Fittings, Pipe Hangers, Pipe Supports, Flanges and Associated Seals

  • MSS SP-43 – Wrought Stainless Steel Butt-Welding Fittings Including Reference to Other Corrosion Resistant Materials
  • MSS SP-75 – Specifications for High Test Wrought Buttwelding Fittings
  • MSS SP-73 – Brazing Joints for Copper and Copper Alloy Pressure Fittings
  • MSS SP-83 – Class 3000 Steel Pipe Unions, Socket-Welding and Threaded
  • MSS SP-97 – Integrally Reinforced Forged Branch Outlet Fittings — Socket Welding, Threaded, and Buttwelding Ends
  • MSS SP-106 – Cast Copper Alloy Flanges and Flanged Fittings Class 125,150, and 300
  • MSS SP-119 – Factory-Made Wrought Belled End Socket Welding Fittings

Difference between “Standard” and “Codes”:

Piping codes imply the requirements of design, fabrication, use of materials, tests and inspection of various pipe and piping system. It has a limited jurisdiction defined by the code. On the other hand, piping standards imply application design and construction rules and requirements for pipe fittings like adapters, flanges, sleeves, elbows, union, tees, valves etc. Like a code, it also has a limited scope defined by the standard.

Factors affecting standards: “Standards” on pipe fittings are based on certain factors like as follows:

  • Pressure-temperature ratings
  • Size
  • Design
  • Coatings
  • Materials
  • Marking
  • End connections
  • Dimensions and tolerances
  • Threading
  • Pattern taper etc.

BSP: British Standard Pipe

BSP is the U.K. standard for pipe fittings. This refers to a family of standard screw thread types for interconnecting and sealing pipe ends by mating an external (male) with an internal (female) thread. This has been adopted internationally. It is also known as British Standard Pipe Taper threads (BSPT )or British Standard Pipe Parallel (Straight) threads (BSPP ). While the BSPT achieves pressure tight joints by the threads alone, the BSPP requires a sealing ring.

JIS: Japanese Industrial Standards

This is the Japanese industrial standards or the standards used for industrial activities in Japan for pipe, tube and fittings and published through Japanese Standards Associations.

NPT: National Pipe Thread

National Pipe Thread is a U.S. standard straight (NPS) threads or for tapered (NPT) threads. This is the most popular US standard for pipe fittings. NPT fittings are based on the internal diameter (ID) of the pipe fitting.

BOLTS & NUTS

We are manufacturer of Flange bolts & Nuts and supply high quality

  • A193 = This specification covers alloy and stainless steel bolting material for pressure vessels, Valves, flanges, and fittings for high temperature or high pressure service, or other special purpose applications.
  • A320 = Standard Specification for Alloy-Steel and Stainless Steel Bolting Materials for Low-Temperature Service.
  • A194 = Standard specification for nuts in many different material types.

AN: Here, “A” stands for Army and “N” stands for Navy

The AN standard was originally designed for the U.S. Military. Whenever, a pipe fitting is AN fittings, it means that the fittings are measured on the outside diameter of the fittings, that is, in 1/16 inch increments.

For example, an AN 4 fitting means a fitting with an external diameter of approximately 4/16″ or ¼”. It is to be noted that approximation is important because AN external diameter is not a direct fit with an equivalent NPT thread.

Dash (-) size

Dash size is the standard used to refer to the inside diameter of a hose. This indicates the size by a two digit number which represents the relative ID in sixteenths of an inch. This is also used interchangeably with AN fittings. For example, a Dash “8” fitting means an AN 8 fitting.

ISO: International Organization for Standardization

ISO is the industrial pipe, tube and fittings standards and specifications from the International Organization for Standardization. ISO standards are numbered. They have format as follows:

“ISO[/IEC] [IS] nnnnn[:yyyy] Title” where

  • nnnnn: standard number
  • yyyy: year published, and
  • Title: describes the subject

How are pipe fittings measured?

Pipe fittings are measured by their diameter, wall thickness (known as “schedule”), and shape or configuration. (Fittings are also defined by their material grade and whether they are welded or seamless.)

Diameter refers to outside diameter of a pipe or fitting.

The North American standard is known as Nominal Pipe Size (NPS). The International Standard is known as Diameter Nominal (DN). Pipes and fittings are actually made in similar sizes around the world: they are just labeled differently.

From ½ in to 12 inch “Nominal Pipe Size”, outside diameters are slightly larger than indicated size; inside diameters get smaller as schedules grow.

From 14 in and larger “Nominal Pipe Size”, outside diameters are exactly as indicated size; inside diameters get smaller as schedules grow.
As with other North American standards (inch, foot, yard, mile, …), many pipe standards (diameters up to 12 inch and wall thickness) are based on historical precedents (a toolmaker’s dies during US Civil War) rather than a “scientific” method.

Schedule Numbers

The schedule numbers are used by the ANSI (American National Standards Institute) to denote wall thickness. The schedule numbers encompass all pipe dimensions beginning at NPS 1/8” up NPS 36”. Note that this configuration is only for fittings that match with a particular ANSI schedule number.

Nominal Pipe Size (NPS) is a North American set of standard sizes for pipes used for high or low pressures and temperatures.

  • Schedule, often shortened as sch, is a North American standard that refers to wall thickness of a pipe or pipe fitting. Higher schedules mean thicker walls that can resist higher pressures.
  • Pipe standards define these wall thicknesses: SCH 5, 5S, 10, 10S, 20, 30, 40, 40S, 60, 80, 80S, 100, 120, 140, 160, STD, XS and XXS. (S following a number is for stainless steel. Sizes without an S are for carbon steel.)
  • Higher schedules are heavier, require more material and are therefore more costly to make and install.

What does “schedule” mean for pipe fittings?

Schedule, often shortened as SCH, is a North American standard that refers to wall thickness of a pipe or pipe fitting.

What is schedule 40, SCH80?

Higher schedules mean thicker walls that can resist higher pressures.

Pipe standards define these wall thicknesses: SCH 5, 5S, 10, 10S, 20, 30, 40, 40S, 60, 80, 80S, 100, 120, 140, 160, STD, XS and XXS.
(S following a number is for stainless steel. Sizes without an S are for carbon steel.)

Higher schedules are heavier, require more material and are therefore more costly to make and install.

General standard

StandardSpecification
ASTM A234Standard Specification for Piping Fittings of Wrought Carbon Steel and Alloy Steel for Moderate and High Temperature Service
ASTM A420Standard Specification for Piping Fittings of Wrought Carbon Steel and Alloy Steel for Low-Temperature Service
ASTM A234 WPBASTM A234 is Standard Specification for steel pipe fittings includes carbon and alloy steel material for moderate and high temperature services. WPB is one of the steel grade in this standard
ASME B16.9ASME B16.9 Standard covers overall dimensions, tolerances,ratings, testing, and markings for factory-made wrought buttwelding fittings in sizes NPS 1⁄2 through NPS 48 (DN 15 through DN 1200).
ASME B16.28ASME B16.28 Standard covers ratings, overall dimensions, testing, tolerances, and markings for wrought carbon and alloy steel buttwelding short radius elbows and returns.
MSS SP-97MSS SP-97 Standard Practice covers essential dimensions, finish, tolerances, testing, marking, material, and minimum strength requirements for 90 degree integrally reinforced forged branch outlet fittings of buttwelding, socket welding, and threaded types.
ASTM A403Standard Specification for Wrought Austenitic Stainless Steel Piping Fittings.

Wide variety for all areas of application

DINENASME
St 35.8 I
St 35.8 III
15 Mo 3
13 CrMo 4 4
10 CrMo 9 10
St 35 N
St 52.0
St 52.4
P235GH-TC1
P235GH-TC2
16Mo3
13CrMo4-5
10CrMo9-10
X10CrMoVNb9-1
P215NL
P265NL
L360NB
L360NE
P355N
P355NL1
P355NH
WPB
WPL6
WPL3
WPHY 52
WP11
WP22
WP5
WP9
WP91
WP92

ASTM A234

ASTM A234/ASME SA234M standard specification for piping fittings of wrought carbon steel and alloy steel for moderate and high temperature service.

Chemical Composition (%) of ASTM A234/A234M

GradeTypeCSiSPMnCrNiMoOtheróbósδ5
WPB0.30.1min0.0580.050.29-1.060.40.40.15V:0.06;Nb:0.02415-58524022197
WPC0.350.1min0.0580.050.29-1.060.40.40.15V:0.06;Nb:0.02485-65527522197
WP10.280.1-0.50.0450.0450.3-0.90.44-0.65380-55020522197
WP12 CL10.05-0.20.60.0450.0450.3-0.80.8-1.250.44-0.65415-58522022197
WP12 CL20.05-0.20.60.0450.0450.3-0.80.8-1.250.44-0.65485-65527522197
WP11 CL10.05-0.150.5-10.030.030.3-0.61-1.50.44-0.65415-58520522197
WP11 CL20.05-0.20.5-10.040.040.3-0.81-1.50.44-0.65485-65527522197
WP11 CL30.05-0.20.5-10.040.040.3-0.81-1.50.44-0.65520-69031022197
WP22 CL10.05-0.150.50.040.040.3-0.61.9-2.60.87-1.13415-58520522197
WP22 CL30.05-0.150.50.040.040.3-0.61.9-2.60.87-1.13520-69031022197
WP5 CL10.150.50.030.040.3-0.64-60.44-0.65415-58520522217
WP5 CL30.150.50.030.040.3-0.64-60.44-0.65520-69031022217
WP9 CL10.1510.030.030.3-0.68-100.9-1.1415-58520522217
WP9 CL30.1510.030.030.3-0.68-100.9-1.1520-69031022217
WPR0.20.050.0450.4-1.061.6-2.24435-60531522/28217
WP910.08-0.120.2-0.50.010.020.3-0.68-9.50.40.85-1.05See sdandard585-76041520248
WP9110.09-0.130.1-0.50.010.020.3-0.68.5-10.50.40.9-1.1See sdandard620-84044020248
Notes:

For each reduction of 0.01% below the specified C maximum, an increase of 0.06% Mn above the specified maximum will be permitted, up to a maximum of 1.35%.
The sum of Cu, Ni, Cr, and Mo shall not exceed 1.00%.
The sum of Cr and Mo shall not exceed 0.32%.
The maximum carbon equivalent (C.E.) shall be 0.50, based on heat analysis and the formula C.E.=C+Mn/6+(Cr+Mo+V)/5+(Ni+Cu)/15.

Mechanical properties of ASTM A234

Tensile RequirementsWPBWPC, WP11CL2WP11CL1 WP11CL3
Tensile Strength, min, ksi[MPa]
(0.2% offset or 0.5% extension-under-load)
60-85
[415-585]
70-95
[485-655]
60-85
[415-585]
 75-100
[520-690]
Yield Strength, min, ksi[MPa]32
[240]
40
[275]
30
[205]
45
[310]

ASTM A403

ASTM A403 Standard specification covers the standard for wrought austenitic stainless steel fittings for pressure piping applications.

Chemical Composition (%) of ASTM A403

Steel No.TypeCSiSPMnCrNiMoOtheróbósδ5
WP3040.0810.030.045218-208-1151520528
WP304H0.04-0.110.030.045218-208-1151520528
WP304L0.03510.030.045218-208-1348517028
WP304LN0.030.750.030.045218-208-10.5N2:0.1-0.1651520528
WP304N0.080.750.030.045218-208-11N2:0.1-0.1655024028
WP3090.1510.030.045222-2412-1551520528
WP3100.151.50.030.045224-2619-2251520528
WP3160.0810.030.045216-1810-142-351520528
WP316H0.04-0.110.030.045216-1810-142-351520528
WP316LN0.030.750.030.045216-1811-142-3N2:0.1-0.1651520528
WP316L0.03510.030.045216-1810-162-348517028
WP316N0.080.750.030.045216-1811-142-3N2:0.1-0.1655024028
WP3170.0810.030.045218-2011-153-451520528
WP317L0.0310.030.045218-2011-153-451520528
WP3210.0810.030.045217-209-13Ti:5C-0.751520528
WP321H0.04-0.110.030.045217-209-13Ti:4C-0.751520528
WP3470.0810.030.045217-209-13Nb+Ta:10C-1.151520528
WP347H0.04-0.110.030.045217-209-13Nb+Ta:8C-151520528
WP3480.0810.030.045217-209-13Ta:0.151520528
WP348H0.04-0.110.030.045217-209-13Ta:0.151520528
Notes:

For each reduction of 0.01% below the specified C maximum, an increase of 0.06% Mn above the specified maximum will be permitted, up to a maximum of 1.35%.
The sum of Cu, Ni, Cr, and Mo shall not exceed 1.00%.
The sum of Cr and Mo shall not exceed 0.32%.
The maximum carbon equivalent (C.E.) shall be 0.50, based on heat analysis and the formula C.E.=C+Mn/6+(Cr+Mo+V)/5+(Ni+Cu)/15.

Mechanical properties of ASTM A403

GradeUNSTensile Strength, minYield Strength,minElongation min % in 4D
ksiMPaksiMPaLongit %Trans%
ALLALL75515302052820
304LS3040370485251702820
316LS3160370485251702820
304NS3045180550352402820
316NS3165180550352402820
S3172680550352402820
XM-19S20910100690553802820
S3125494-119650-820443002820
S34565115795604152820
S3322873500271852820

Material Furnished to this specification shall conform to the requirements of specifications A960/A960M including any supplementary requirements that are indicates in the purchase order. Failure to company with the common requirements of Specification A960/A960M constitutes non-conformance with this specification . In case of conflict between this specification and Specification A960/A960M , this specification shall prevail.

ASTM A420

ASTM A420/A420M-07 standard specification for piping fittings of wrought carbon steel and alloy steel for low-temperature service.

ASTM A420 Chemical Composition Requirements

ElementsWPL6, %WPL9, %WPL3, %WPL8, %
Carbon [C]≤0.30≤0.20≤0.20≤0.13
Manganese [Mn]0.50-1.350.40-1.060.31-0.64≤0.90
Phosphorus [P]≤0.035≤0.030≤0.05≤0.030
Sulfur [S]≤0.040≤0.030≤0.05≤0.030
Silicon [Si]0.15-0.400.13-0.370.13-0.37
Nickel [Ni]≤0.401.60-2.243.2-3.88.4-9.6
Chromium [Cr]≤0.30.........
Molybdenum [Mo]≤0.12.........
Copper [Cu]≤0.400.75-1.25
Columbium [Cb]≤0.02.........
Vanadium[V]≤0.08.........
*For grade WPL6, the limit for Columbium may be increased up to 0.05% on heat analysis and 0.06% on product analysis.
*Fittings of WPL3 made from plate or forgings may have 0.90 % max manganese.
*Fittings of WPL8 made from plate may have 0.98 % max manganese.

ASTM A420 Mechanical Properties

ASTM A420/ A420MTensile Strength, min.Yield Strength, min.Elongation %, min
GradeksiMPaksiMPaLongitudinalTransverse
WPL665-95415-655352402212
WPL963-88435-6104631520
WPL365-90450-620352402214
WPL8100-125690-8657551516
*All the elongation values are on the basis of standard round specimen, or small proportional specimen, min % in 4 D.

ASTM A234 is Standard Specification for steel pipe fittings includes carbon and alloy steel material for moderate and high temperature services.

ASME B16.9

ASME B16.9 Standard covers overall dimensions, tolerances,ratings, testing, and markings for factory-made wrought buttwelding fittings in sizes NPS 1⁄2 through NPS 48 (DN 15 through DN 1200).

ASME / ANSI B16.9 dimension

NominalOutside Diameter90° Elbows45° Elbows180° Returns
Pipe Size
Long RadiusShort RadiusLong RadiusLong Radius
(inches)(mm)(inches)Center to FaceCenter to FaceCenter to FaceRadiusCenter to CenterBack to face
(inches)(inches)(inches)(inches)(inches)(inches)
1/221.30.841.55/821.875
3/426.71.051.1257/162.251.6875
133.41.3151.517/832.1875
1.2542.21.661.8751.2513.752.75
1.548.31.92.251.51.12534.53.25
260.32.375321.375464.1875
2.5732.8753.752.51.7557.55.1875
388.93.54.532696.25
3.5101.645.253.52.25710.57.25
4114.34.5642.58128.25
5141.35.5637.553.125101510.3125
6168.36.625963.75121812.3125
8219.18.6251285122416.3125
10273.110.7515106.25153020.375
12323.912.7518127.5183624.375

Tolerances of Welded Fittings

NOMINAL PIPE SIZE NPSANGULARITY TOLERANCESANGULARITY TOLERANCES
SizeOff Angle QOff Plane P
½ to 40.030.06
5 to 80.060.12
10 to 120.090.19
14 to 160.090.25
18 to 240.120.38
26 to 300.190.38
32 to 420.190.5
44 to 480.180.75
All dimensions are given in inches. Tolerances are equal plus and minus except as noted.
1. Out-of-round is the sum of absolute values of plus and minus tolerance.
2. This tolerance may not apply in localized areas of formed fittings where increased wall thickness is required to meet design requirements of ASME B16.9.
3. The inside diameter and the nominal wall thicknesses at ends are to be specified by the purchaser.
4. Unless otherwise specified by the purchaser, these tolerances apply to the nominal inside diameter, which equals the difference between the nominal outside diameter and twice the nominal wall thickness.

MSS SP-97

MSS SP-97 Standard Practice covers essential dimensions, finish, tolerances, testing, marking, material, and minimum strength requirements for 90 degree integrally reinforced forged branch outlet fittings of buttwelding, socket welding, and threaded types.

Buttwelding Ends

Nominal wall Thickness : tEnd Preparation
t<5mm (for austenitic alloy steel t<4mm)Cut square or slightly chamfer at manufacturer ‘ s option
5Plain Bevel as in sketch ( a ) above
t>22mmCompound Bevel as in sketch ( b ) above

Chemical Composition Requirements of MSS SP 75

ElementsValue, %
Carbon (C)≤0.30
Manganese (Mn)≤1.60
Phosphorus (P)≤0.035
Sulfur (S)≤0.035
Copper (Cu)≤0.50
Nickel (Ni)≤0.50
Silicon (Si)≤0.50
Chromium (Cr)≤0.25
Molybdenum (Mo)≤0.13
Vanadium (V)≤0.13
Columbium (Cb)≤0.10
Titanium(Ti)≤0.05
*1. The sum of Cu, Ni, Cr and Mo shall not exceed 1%.
*2. Carbon equivalent C.E.=C+Mn/6+(Cr+Mo+V)/5+(Ni+Cu)/15 shall not exceed 0.45%.

Manufacturing Standards of Buttweld Pipe End, Buttweld Pipe Cap

  • ASME: ANSI B16.9, ANSI B16.28, MSS-SP-43
  • DIN: DIN2605, DIN2615, DIN2616, DIN2617, DIN28011
  • EN: EN10253-1, EN10253-2
  • ASTM A403 – ASME SA403 Standard Specification for Wrought Austenitic Stainless Steel Piping Fittings
  • ASME B16.9 Factory-Made Wrought Fittings Buttwelding
  • ASME B16.25 Buttwelding Ends
  • ASME B16.28 Wrought Steel Short Radius Elbows and Buttwelding Returns
  • MSS SP-43 Wrought and Fabricated Butt-Welding Fittings for Low Pressure, Corrosion Resistant Applications

Buttweld Pipe End Material Grades

  • Stainless Steel Pipe Cap ASTM A403 WP Gr. 304, 304H, 309, 310, 316, 316L, 317L, 321, 347, 904L
  • Carbon Steel Pipe Cap ASTM A 234 WPB , WPBW, WPHY 42, WPHY 46, WPHY 52, WPH 60, WPHY 65 & WPHY 70.
  • Low Temperature Carbon Steel Pipe Cap ASTM A420 WPL3, A420 WPL6
  • Alloy Steel Pipe Cap ASTM / ASME A/SA 234 Gr. WP 1, WP 5, WP 9, WP 11, WP 12, WP 22, WP 91
  • Duplex Pipe Cap ASTM A 815, ASME SA 815 UNS NO S31803, S32205. Werkstoff No. 1.4462
  • Nickel Alloy Pipe Cap ASTM / ASME SB 336 UNS 2200 ( NICKEL 200 ), UNS 2201 (NICKEL 201 ), UNS 4400 (MONEL 400 ), UNS 8020 ( ALLOY 20 / 20 CB 3, UNS 8825 INCONEL (825), UNS 6600 (INCONEL 600 ), UNS 6601 ( INCONEL 601 ), UNS 6625 (INCONEL 625), UNS 10276 ( HASTELLOY C 276 )

Benefits

The use of stub ends has these two advantages:

Reduces the overall cost of the flanged joint Generally, the lap joint flange is of a lower grade than the material of the stub end and the pipework, thus saving the total weight of high-grade material used for the flanged joint.

Reduces the overall cost of the flanged joint

Generally, the lap joint flange is of a lower grade than the material of the stub end and the pipework, thus saving the total weight of high-grade material used for the flanged joint.

Example:

For an SS316 pipe, instead of using a full 316 welding neck flange, a combination of an SS316 stub end and a carbon steel lap joint flange would do the same exact job, but the total weight of SS316 material would be lower, and the cost as well.

Essentially, stub ends allow to minimize the weight of high-grade material in stainless, duplex, and nickel alloy piping, saving costs. Of course, the bigger the diameter and the class of the flanges, the higher the saving!

Commercial benefits

Commercial advantages are that the Stub End, will be wetted and it must be made of a grade of material that meets the process design and service conditions of the pipeline. However, the Lap Flange is un-wetted and it can be made of a lower grade of material as long as it meets
the mechanical strength requirements of the piping systems.

Installation benefits

The “loose” Flange concept of a Lap Joint, is very beneficial during field installation of piping systems. If two spools are to be mated up in the field, having one Flange that can be rotated is very advantageous when aligning the bolt holes, prior to the introduction of the Stub bolt and the accompanying nuts. The facility of easier orientation and alignment of bolt holes, is of particular use it there is a spool that
has to be removed frequently, if positive isolation is a process requirement.

Stub Ends limitations

A Lap Joint consists of two independent components that are not integrated with a weld and like for like in size/pressure class/material it lacks the mechanical strength and capabilities to withstand fatigue, like a one piece Weld Neck Flange or a welded together Slip On or Socket Weld Flanges. In cyclic services, collars EN 1092-1 type 35 PN 16-25-40 are used instead of stub ends (especially to close pumps and compressors). If carefully consideration is given to Process Design condition, the service and the final application, then a Lap Joint Flange mechanical connection are a valid and cheaper method for installing piping systems compared to the use of standard flanges.

A stud end and a lap joint flange can be used together as an alternative way to make a flanged connection than welding neck flanges.

Applications

Why use Stub EndsStub end is widely used in the petroleum, chemical, power, gas, metallurgy, shipbuilding and construction industries. It is made from high quality raw materials, and available in a variety of sizes and designs. The combination of stub ends and backing flanges is an alternative way to join pipes compared to the use of standard flanges.

90° Lateral Wye R500 DN150 Export to Pilipinas with lap-joint flanges

This solution is used in these typical scenarios:

  • Applications where rotating back flanges are preferred (to facilitate bolting)
  • Pipelines in costly materials, as stainless steel, duplex, super-austenitic (example 6Mo), nickel alloy, titanium and zirconium: indeed, the use of stub ends for this type of pipelines helps End-Users and EPC Contractors reduce the total weight of the flanged joints and their total cost (example: in a stainless steel pipeline, carbon steel backing flanges can be used instead of standard stainless steel flanges – as they do not get in contact with the fluid conveyed by the pipeline – “unwetted materials”)
  • High pressure pipelines

Why use Stub Ends?

A stud end and a lap joint flange can be used together as an alternative way to make a flanged connection than welding neck flanges.

The two devices to be combined, in this case, are:

  • The stub end, which is essentially a piece of pipe, with one end flared outwards and the other prepared to be welded to a pipe of the same bore size (NPS = nominal pipe size), material and wall thickness. The most widely used fabrication tool for stub ends is the flaring machine, which is able to flare the end of the pipe and then cuts it to length.
  • A Lap Joint Flange, which is used to actually bolt the two lengths of pipe together.

Packing

For packing of carbon steel flanges with painting,we would use the bubble wrap to protect the painting.For flanges without painting or oiled with long-term shipment,we would suggest client to use the anti-tarnish paper and plastic bag to prevent the rust. Packing reducers in wooden cases

Wrap the plastic tightly around the pipe to protect the tee

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FAQ

Q: How long is your delivery time? A: The delivery time of customized products is generally 25 35 days, and non customized products are generally shipped within 24 hours after payment. Q: Do you provide samples? Is it free? A: If the value of the sample is low, we will provide it for free, but the freight needs to be paid by the customer. But for some high value samples, we need to charge a fee. Q: What are your payment terms? A: T/T 30% as the deposit,The balance payment is paid in full before shipment Q: What is the packaging and transportation form? A: Non steaming wooden box and iron frame packaging. Special packaging is available according to customer needs. The transportation is mainly by sea. Q: What is your minimum order quantity? A: There is no minimum order quantity requirement. Customized products are tailor made according to the drawings provided by the customer.