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Understanding The Different Tees & Crosses

Tees straight and decreasing

The principal function of Tees is that their primary function Tee is to create an 90deg branch from the main line of pipe. In the standard, there are two possibilities for the equal tee as well as the reducing Tee. An equal the tee (or stainless straight tees) is employed because the branch is the same diameter as the runpipe. The reducing tee can be used since the branch is smaller in diameter than the run-pipe.

Dimensions and Standards

When we speak of an tee NPS 3 x 2, an straight or equal tee would be meant to be. In a tee with a NPS 3 x 2,, a reduced tee is the intention. However, a officially reduced the tee is indicated with three diameters, specifically 3x3x2 (A B x A). The measure A and B is what is known as the nominal Pipe Size of the Run-Pipe. The C is the measure for the Nominal Pipe Dimensions of the Outlet.

The term “superfluous” is actually redundant and comes from the time when tees were offered in three different diameters at the ends for example, 4 3 x 2 (A B C). For this particular application, it is essential to indicate 3 sizes.

These kinds of tees are likely to be no longer available. The use of a similar tee using an eccentric or concentric reducer has become the standard procedure.

Straight or equal buttwelding Tee is offered in all common diameters.

A Reducing Tee is not as wide, since certain diameters aren’t produced or are not manufactured.

For illustration.. Reduced NPS tee 6×4 is a standard product for many suppliers, but an reducing tee NPS 16 x 2 will likely not offered by any vendor.

It is also not economically feasible to utilize an NPS 16 Tee with an NPS 2 outlet. In these situations, it is recommended that a Branch Fitting is used or an Branch Connection will be established.

Cross Tee

Alongside the standard tees, there are also straight and cutting crosses. Straight crosses are typically standard items, while reducing ones are usually difficult to find. I’ve never worn those T-shirts and have never encountered in the real world at the very least, not in the chemical and petro industries. They are likely to be utilized when space is restricted, such as in revisions, in the shipping industry , etc.

Wall Thickness Tee

Based on the form of a tee wall thickness could be an important element. ASME B16.9 is a standardization of length-to width, center-to end dimensions and a few “squareness” tolerances for dimensional measurements.
The thickness of the wall at location of the weld line is also standardized, however not throughout the rest of the fitting. The standard stipulates that the tolerance must be within 12.5 percent of the minimum required diameter of the wall. The maximum tolerance is stated only at the edges of the pipe.

There are many suppliers of welding Tees (and elbows) offer a different schedule with a higher in thickness, so that enough wall thickness, following the forming the tee, remains. In Tee’s it is the diameter of the crotch (T) is different between different manufacturers and some even establish it as a standard, 1.3 times the thickness of the wall to ensure the crotch is maintained.

…it is anticipated that some part of the formed fittings will need to be more robust than that of the pipe the fitting intended to be installed.

Since there isn’t a upper limit for certain components that are fitted, the purchaser himself must specify his specifications. In accordance with a specification from the customer the manufacturer must confirm that the made tee meets the specifications of the customer.

You can accomplish this by using additional drawings, along with wall thickness measurements, etc. Verified by an independent third party or a customer inspector.

The additional tests all cost money, and it is possible that the costs are several times more expensive, than the Tee itself.