MSS SP-97 is a standard developed by the Manufacturers Standardization Society (MSS) that specifically covers Integrally Reinforced Forged Branch Outlet Fittings, commonly known as “Olets” or branch fittings. This standard defines the design, materials, dimensions, pressure ratings, marking, inspection, and testing requirements for these fittings.
The MSS SP-97 standard applies to various types of Olet branch fittings, including Sockolets, Weldolets, and Threadolets, which are typically used to create branch connections on a main pipeline for connecting to a branch line.
Scope of MSS SP-97
This Standard Practice covers essential dimensions, finish, tolerances, testing, marking, material, and minimum strength requirements for 90 and 45 degree integrally reinforced forged branch outlet fittings of buttwelding, socket welding, and threaded types.
These fittings are designated by their size, type, and class, as shown in Table 1.
MATERIAL
The material for fittings, under this Standard Practice, shall consist of forging, bar, and seamless tubular products. The materials shall conform to the requirements of the WP Grade seamless construction materials in ASTM Fitting Specifications A234/A234M, A403/A403M, A420/A420M, or A815/A815M; or the ASTM Forging Specifications A105/A105M, A182/A182M, or A350/A350M.
SIZE
The 90 and 45 degree branch outlet sizes considered in this Standard Practice are shown in Table 1. Size on size fittings shall be limited to outlet sizes NPS 1/2 (DN 15) and larger.
The run (header) pipe size is limited only by the pipe size range listed for each type fitting class.
The manufacturer has the option to consolidate run sizes for a given branch size for economic reasons, provided the designated consolidation gap distance between the run pipe radius and the fitting inlet radius does not exceed 1/16″ (1.6 mm). See Figure 1.
MARKING
Each fitting shall be permanently marked with the required identification by raised lettering, and/or by stamping, electroetching or vibro tool.
- The marking shall include (but it is not limited to) the following:
- Manufacturer’s name or trademark.
- Material Identification The material shall be identified in accordance with the marking requirements of the applicable ASTM Specifications, including Heat Identification.
- Class The Fitting Class – “STD” (Standard), “XS” (Extra Strong), “SCH 160” (Schedule 160), “3000” or “6000”. Alternatively, the designation 3M or 6M, as applicable, may be used where “M” stands for 1,000.
- Size The nominal size of the pipe that the fitting’s marking identifies – Run (or consolidated range) NPS (DN) x Outlet NPS (DN).
- SP 97 This marking indicates compliance with MSS SP-97.
Where size and shape of fittings do not permit all of the above markings, they may be omitted in the reverse order given above.
DIMENSIONS
Tables 2 through 7 show the fitting’s dimensional requirements in customary units or inches (decimal).
MSS SP 97 90° Branch Outlets – Buttwelding Dimensions
MSS SP 97 90° Branch Outlets – Threaded Dimensions
MSS SP 97 90° Branch Outlets – Socket Welding Dimensions
MSS SP 97 45° Branch Outlets – Buttwelding Dimensions
MSS SP 97 45° Branch Outlets – Threaded Dimensions
MSS SP 97 45° Branch Outlets – Socket Welding Dimensions
Why SSM is Your Trusted Supplier of Forged Pipe Fittings
SSM is dedicated to upholding high-quality standards, precise manufacturing, and stringent quality control. Our MSS SP-97 pipe fittings, which include integrally reinforced forged branch fittings with socket weld, threaded, and butt weld ports, are manufactured to meet or exceed industry specifications. This ensures durability and reliability in demanding applications.
With our extensive experience and professional team, SSM offers customized solutions to meet your specific needs, ensuring on-time delivery and competitive prices.
FAQ
MSS SP-97 fittings are commonly used in industries like oil and gas, petrochemicals, power generation, and other applications requiring high-strength and reliable branch connections in piping systems.
Compliance with MSS SP-97 ensures that branch outlet fittings meet the necessary quality, safety, and performance standards for reliable and secure connections in piping systems.
More information about MSS SP 97:
