Piping Tees are used to either combine flow from two streams or divide the primary flow into two streams. The word is most likely derived from its similarity to the English letter Tee.
The phrases "header" or "branch" are frequently used to describe the primary run pipe. Run pipe size is limited to being smaller than or equal to run pipe size. Tees are classified as equal, unequal, or declining according to whether the branch size is equal to the run size.
Tees are often designed using ASME B 16.9 or B 16.11 standards. A tee is often created by forging and is always normal or perpendicular to the pipe axis.
Types of Piping Tee Connections
The branch size and end connection are used to categorize piping tee connections.
Depending on the branch size, there are two types of pipe tee connections. As follows:
- Equal Tee, and
- Reducing Tee
Equal Piping Tee: Equal Tee pipe fittings are used when the branch size and the run pipe are the same.
Reducing Piping Tee: When using a reducing tee, the branch size is smaller than the run pipe size. The size of the branches is constrained. It cannot be made small enough. For instance, a reducing tee made of 16-inch pipe is available in branch sizes up to 6-inch. The 16" x 4" piping tee is not produced. Reducing piping T-connectors are typically made up of a branch pipe size one size smaller than half the parent pipe size. This rule is in effect until 28. "
Based on end connections, tees are classified as follows:
- Socket Welded Tees
- Screwed-End Tees
- Butt Welding Tees
- Flanged Tees
Socket Welded Tees
- These are typically forged and utilized on services where socket welded connections are allowed up to a 2" run size.
- ASME B16.11 is the applicable dimensional standard, and socket welded elbow material specifications, including ratings, apply.
- To a 1 1/2" run size, socket welded tees are typically used in business.
Screwed-end Tees
The same rating, dimensional, and material standards that apply to screwed elbows also apply to them.
Butt welding Tees
- ANSI B16.9 is the dimension standard appropriate for equal and unequal tees. These range in size from 1/2" to 48".
- Uneven butt welding tees with branches up to one size smaller than half the run size are available, for example. Uneven tees come in sizes 8" x 6", 8" x 5", 8" x 4", and 8" x 3 1/2" if the run size is 8.
- The material criteria and applicable pressure-temperature rating are the same as those for butt-welding elbows.
- When socket weld joints are not allowed, smaller sizes of butt welding tees are typically used for size 2 and larger jobs.
Flanged Tees
Their application, along with the pressure rating, dimensional, and material specifications, is identical to those for flanged elbows.
The butt-welded Tee is the most common connection type used in standard large-bore pressure pipework. When Tee is defined, Caesar automatically calculates the SIF value at tee connections using the ASME B 31.3 (Appendix D) formula. The following figure illustrates how Caesar typically defines the Tee connections.
