This article is about SAES-L-110 which is about Limitations on Pipe Joints and Components and download SAES-L-110 PDF for piping and mechanical engineers, supervisors and project managers. This is saudi aramco standard based on international codes and standards and useful for piping and mechanical engineering knowledge to get job as engineers, QC Supervisors and QC managers, Engineering managers and technicians.
SAES-L-110 PDF Download
SAES-L-110SAES-L-110 PDF Download – Limitations on Pipe Joints and Components
This standard SAES-L-110 specifies limitations and requirements for different types of joints and components used in metallic pressure piping systems. It applies to both plant piping and pipelines, complementing the provisions of ASME B31.1, B31.3, B31.4, and B31.8 piping codes.
The standard focuses on metallic pipe fittings, such as bends, miters, laps, and branch connections, used in various applications. It outlines specific requirements for their selection and usage. However, it does not cover tube fittings or other specialty fittings, as they fall outside the scope of this standard.
The purpose of these additional requirements is to ensure the proper functioning, safety, and integrity of metallic piping systems in accordance with Saudi Aramco guidelines. By addressing specific joint types and components, the standard provides guidance on their appropriate selection, installation, and use within the context of SAES-L-100.
Welded Joints
Welded joints play a crucial role in metallic piping systems, and this standard provides specific guidelines for their implementation. Here are the key points related to welded joints:
Pipe Welds:
- Welds in metallic piping must adhere to the requirements outlined in welding standards such as SAES-W-011, SAES-W-012, and SAES-W-013, along with other referenced standards.
- When the wall thickness ratio between the joined pipes is 1.5 or less, the joint design details should comply with the respective ASME B31 design code.
- If the wall thickness ratio exceeds 1.5, the end preparations and geometry of the joint should follow ASME B16.25 “Butt Welding Ends.”
- In cases where the wall thickness of the fitting or pipe at the welding end is greater than that of the matching pipe, resulting in unequal external and/or internal diameters, the welded joint design should adhere to Figure 434.8.6-2 (a) of ASME B31.4, regardless of the design code used.
Socket Welds:
- The maximum size of socket-welded joints in hazardous services for new construction should be limited to 1½-inch. However, a maximum size of 2-inch can be used in hazardous service for maintenance, minor field modifications of existing piping systems, or when necessary to match existing equipment connections.
- For sour service (service involving hydrogen sulfide), it is generally recommended to avoid socket-welded joints. If they cannot be avoided, the maximum size of socket-welded joints should be limited to 1-inch.
- Socket weld joints should not be used in locations prone to high vibration, such as high-velocity gas control valves and reciprocating pumps.
It’s important to follow these guidelines to ensure the integrity and reliability of the welded joints in metallic piping systems.
Prohibited Piping Joints and Components
Certain piping joints and components are prohibited in pressure piping systems within the scope of SAES-L-100. Here are the details:
Prohibited Piping Joints and Components:
a) Caulked joints are not allowed.
b) Soldered, brazed, and braze-welded joints are not permitted.
c) Expanded joints, which are slip-on joints using an O-ring to seal the pressure, are prohibited. d) Bell-type and packed joints are not allowed unless specified otherwise in this standard document.
Threaded Joints: 7.1 Threaded joints should generally be avoided in services where crevice corrosion, severe erosion, or cyclic conditions may occur. The following guidelines apply to threaded joints:
- Threaded connections should conform to taper pipe thread (NPT) standards as specified in ASME B1.20.1, unless specific connections require otherwise. However, threaded connections for fire services should comply with SAES-B-017.
- In hazardous services, the maximum size of threaded connections for standard fittings and valves should be limited to 1½-inch. However, a maximum size of 2-inch can be used for maintenance, minor field modifications of existing piping systems, or for threaded specialty devices such as scraper signals and access fittings for corrosion monitoring. Threaded connections should not be used in hydrogen service.
- In non-hazardous services, the maximum size of threaded connections for standard fittings and valves should be limited to 3-inch. A maximum size of 4-inch is permitted for special items such as fire hydrants, unless a larger size is approved by the assigned Chairman of the Piping Standards Committee for the specific application.
- The engaged threads on the pipe should meet the minimum length requirements specified in ASME B1.20.1 for taper pipe thread. The minimum number of engaged pipe threads should comply with the requirements of Table 1.
- PTFE (Teflon) tape should not be used on threaded connections for service temperatures greater than 204°C.
Adhering to these guidelines helps ensure the appropriate selection and usage of threaded connections in metallic piping systems.
Flanged Joints
Flanged joints have specific considerations and limitations outlined in SAES-L-100. Here are the details:
Flanged Joints:
It is recommended to avoid flanged connections in situations where butt-welded joints can be used. This applies to services and locations where leaks are likely to occur (e.g., cyclic or vibration services), or where leaks could pose serious hazards (e.g., potentially toxic material), or in cases where control of leaks is difficult. The following situations are examples where flanged connections should be avoided:
a) Steam applications in ASME class 900 pressure rating.
b) Fully restrained portions of cross-country pipelines and underwater pipelines.
c) Locations where piping will be subjected to large bending or other external loads.
d) Buried piping systems.
Flanged connections with long exposed bolts for sandwiched components, other than standard spectacle plates and blinds, should not be used in fire hazardous areas unless the bolting is protected by a fire-resistant shield. The shield should meet the requirements specified in Standard Drawing AC-036404-002 or an equivalent method. This requirement is in accordance with SAES-B-006.
The selection of flanges should follow the guidelines provided in SAES-L-109.
By adhering to these guidelines, the appropriate usage of flanged connections can be ensured, considering factors such as potential leaks, hazards, external loads, and fire protection.
Seal Welding of Threaded Joints
Seal welding of threaded joints is permitted to prevent leakage, but it should not be relied upon for the strength of the joint. Here are the details regarding seal welding of threaded joints:
Seal Welding of Threaded Joints: 9.1 Seal welding can be used to prevent leakage in threaded joints. However, it should be noted that the seal weld does not contribute to the strength of the joint.
In the following services and applications, seal welding of all threaded joints up to the first block valve is required: a) Hydrocarbon services. b) Systems involving boiler feed water, condensate, and steam, using ASME Class 300 and higher flange ratings. c) Services involving toxic materials such as chlorine, phenol, hydrogen sulfide, etc. d) Services involving corrosive materials such as acids, caustics, etc. e) Oilfield chemical applications, including corrosion inhibitors, emulsifiers, electrolytes, etc. f) Piping subjected to vibration, whether continuous or intermittent.
Seal welding is not required in the following services and applications: a) Thermowells. b) Bar stock plugs downstream of a seal-welded block valve. c) Special devices like access fittings and scraper signals. d) Joints that require frequent disassembly and are located downstream of a seal-welded block valve, for example, sample connections. e) Instrument piping downstream of the primary instrument isolation valve. f) Pipe union ring threads and joints with elastomer O-rings. g) Threaded joints downstream of a seal-welded root valve, discharging directly to an open drainage system or to the atmosphere. h) Extended body valves with integrally reinforced welding end as per API STD 602.
When seal welding is required, the seal weld should be a fillet weld starting from the outer diameter of the female part. It should be smooth with slight concavity, as permitted by ASME B31, covering all exposed threads without undercut.
PTFE (Teflon) tape or joint compounds should not be used in threaded connections that require seal welding.
By following these guidelines, seal welding can be effectively applied to prevent leakage in threaded joints, ensuring the integrity of the piping system.
Only SAES-L-110 PDF Download by this document you can get know about limitations of pipe joints.
Pipe Fittings General Requirements:
All metallic pipe fittings used in the piping system should be fully compatible with the adjoining pipe. They should also adhere to the limitations specified in SAES-L-136, which provides guidelines for carbon steel line pipe.
The pipe fittings should be sourced from an approved manufacturer in accordance with SAES-L-101. This ensures that the fittings meet the required standards and specifications.
Carbon steel fittings should comply with the specific requirements outlined in 02-SAMSS-005. This standard provides detailed guidelines for the selection, manufacturing, and testing of carbon steel fittings.
Additional requirements apply to fittings used in services with a design minimum temperature ranging from minus 18°C to minus 45°C. These requirements ensure that the fittings are suitable for low-temperature conditions and can withstand the associated challenges.
By following these general requirements, the selection and use of pipe fittings in the piping system can be optimized for compatibility, quality, and adherence to relevant standards and specifications.
Threaded and Socket Welding Fittings:
In hazardous services, threaded and socket welding fittings used for steel piping should conform to ASME B16.11 standards, specifically Class 3000, Class 6000, or higher. These standards ensure the fittings are designed and manufactured to withstand the pressures and requirements of hazardous environments.
Pipe unions in hazardous services are limited to Class 3000 threaded or socket welding forged steel unions in accordance with MSS SP-83. The material used for these unions should be carbon steel per ASTM A105, ASTM A350, or alloy steel per ASTM A182. It’s important to note that pipe unions should not be installed in the pipe section between the main pipe run and the root valve.
Threaded bushings with one size reduction should not be used. If bushings are permitted, only hex head steel bushings should be used. Flush steel bushings are not allowed.
Welding bosses should be made of forged steel, specifically ASTM A105, ASTM A350, or ASTM A182, as applicable. The design and specifications for welding bosses can be referenced from Standard Drawings AE-036175-001 or AD-036643-001.
Integrally reinforced welding outlets, such as Weldolets, Threadolets, Sockolets, etc., of approved design are acceptable. These outlets should be in Class 3000, 6000, or higher as applicable and should abut the pipe wall with a full penetration weld.
11.6 Malleable iron screwed fittings should conform to ASME B16.3 Class 150 and should be galvanized. These fittings are typically limited to non-hazardous services, with the exception of pipe unions which should be Class 300. SAES-L-110 PDF Download and get know about limitations of pipe joints.
11.7 Pipe plugs used in metallic piping should be solid body, bar-stock, or forged steel plugs conforming to ASME B16.11 standards. These plugs ensure a secure and reliable closure for the piping system.
Steel Butt Welding Fittings of SAES-L-110 PDF Download
Carbon steel butt weld fittings made of ASTM A234 Grade WPB and MSS SP-75 materials should conform to the requirements specified in 02-SAMSS-005. These requirements ensure that the fittings meet the necessary quality and performance standards for their intended applications.
All steel butt welding fittings should conform to the specifications outlined in 02-SAMSS-005. This ensures that the fittings meet the required dimensions, tolerances, and other relevant specifications for their proper installation and functionality.
Integrally reinforced welding outlets that are not listed in the SAMS Catalog should be of a design approved by the Chairman of the Piping Standards Committee. This ensures that the design and construction of these outlets meet the necessary standards and requirements. For post-weld heat treatment requirements for welding outlets, reference should be made to SAES-L-350.
Miter elbows are not allowed. If miter bends need to be used, prior approval from the Chairman of the Piping Standards Committee is required. This is to ensure that proper considerations are made for the specific application and that the miter bends meet the necessary standards and requirements.
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