SAES-L-109 PDF – Selection of Flanges, Stud Bolts and Gasket

This article is about SAES-L-109 which is about Selection of Flanges, Stud Bolts and Gaskets and download SAES-L-109 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-109 PDF Download

SAES-L-109

SAES-L-109 Selection of Flanges, Stud Bolts and Gaskets

This standard focuses on the mandatory requirements for the selection of metallic pipe flanges, gaskets, and stud bolts for pressure piping within the scope of SAES-L-100. It serves as a supplement to ASME B31.1, ASME B31.3, ASME B31.4, and ASME B31.8 codes. These codes provide guidelines for the design, construction, operation, and maintenance of various types of piping systems in different industries.

The purpose of this standard is to provide additional specifications and guidelines specifically related to the selection of flanges, gaskets, and stud bolts. It ensures that these components meet the necessary criteria for safe and efficient operation in accordance with Saudi Aramco’s requirements.

General Requirements of SAES-L-109 PDF Download

According to the standard, there are several general requirements for flanges, stud bolts, and gaskets. Here are the key points:

Flanges that are not covered by any Saudi Aramco or industry standards should be designed according to ASME SEC VIII D1, Appendix 2, and ASME SEC VIII D1 Section UG-34 for blind flanges. The design and dimensions of non-standard ring-joint facings should be reviewed by the Chairman of the Piping Standards Committee to ensure compatibility with the selected gaskets.

Components requiring special analysis or proof testing, as specified in ASME B31.3, paragraph 304.7.2, should be reviewed and approved by the Chairman of the Piping Standards Committee in CSD (Corporate Standard Drawing) prior to specification and procurement.

Flanges, stud bolts, and gaskets should be procured from approved manufacturers according to the requirements of SAES-L-101 and the SAP (Saudi Aramco Approved Product) list.

Insulating joints should comply with the mechanical requirements of this standard and be installed as required by the Cathodic Protection Standards for pipelines or for Stray Current Protection on loading lines.

Orifice flanges should comply with ASME B16.36 and SAES-J-100.

Jackscrews should be used to facilitate flange separation for maintenance. However, if flange separators are used, jackscrews are not required.

Flanges equipped with jackscrews should be designed according to Saudi Aramco Standard Drawing AD-036630 or a similar approved design.

For orifice flanges, jackscrews should be installed at the 3 o’clock and 9 o’clock positions.

Furthermore, joint assemblies that require frequent separation, such as orifice plates, spectacle plates, spacers, screens, and drop-out spools, should be considered. Pipe joints should comply with ASME B16.25 and SAES-L-110, while flange welding ends should adhere to applicable ASME/API standards.

Flange Type Selection and Limitations:

Weld Neck Flanges: Weld neck flanges should be the primary selection for flanged joints in metallic piping systems of 2-inch NPS (Nominal Pipe Size) and larger.

Slip-on Flanges: Slip-on flanges are allowed only for category D services.

Slip-on flanges and reducing slip-on flanges should not be used in the following services:

• Flange sizes 20 inches and larger
• Severe cyclic conditions
• Piping systems subject to mechanical vibration.

Slip-on flanges are required to be double-welded, and the flange sealing face should be free from scratches, weld burns, etc. A double-welded slip-on flange has a weld between the pipe and the flange hub and between the pipe and the bore of the flange.

Slip-on flanges should not be fabricated from blind flanges.

Lap-joint Flanges: The use of lap-joint flanges should be avoided and is subject to the following limitations and conditions: Lap-joint flanges should not be used for severe cyclic conditions or in areas subject to high mechanical vibration.

Lap-joint flanges are allowed for:

• Easy alignment of bolt holes
• Special applications to avoid welding dissimilar metals, where the pipe stub-end is made from high alloy material and the flange body is made from carbon steel.
• The lapped flange and stub-end design should comply with ASME SEC VIII D1, Appendix-2.
• Lapped flanges should comply with Standard Drawings AE-036438, AC-036443, and AC-036486 for sizes larger than 24-inch NPS.

Swivel Ring Flanges: For underwater pipe tie-in, swivel ring flanges should comply with Saudi Aramco Standard Drawing AA-036792. If a proprietary design is used, it should be in accordance with ASME SEC VIII D1, Appendix 2.

Ball Swivel Flanges: The use of ball swivel flanges is not permitted.

Compact Flanged Connections: Compact flanged connections, which are tapered flat face with self-energized ring gaskets, designed and fabricated in accordance with Norsok Standard L-005, are acceptable for offshore platforms.

Clamp-Type Flanges: Clamp-type flanges or connectors should conform to API SPEC 6A or be proprietary connectors based on ASME SEC VIII design and approved by the Chairman of the Piping Standards Committee.

Restricted Flange Classes: The following flange classes should not be used: 6.8.1 ASME Class 400 carbon steel flanges for sizes smaller than 30 inches.

ASME Class 75 for any size and material.

Regular Blind Flanges: The use of regular blind flanges tapped with smaller pipes is permitted, provided they meet the size ratio requirements addressed in Table 1.