Tees straight and decreasing
The main purpose 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 in the form of an equal tee and the reducing Tee. An equal toe (or straight tee) is employed because the branch is the same size as the run-pipe. The reducing tee can be used since the branch is smaller in diameter than the runpipe.
Dimensions and Standards
When we speak of an tee NPS 3, an straight or equal tee is designed. In a tee with a NPS 3 x 2,, a reduced tee is the intention. However, a officially reduced Tee will be identified by three diameters, specifically 3x3x2 (A B x A). The measure A and B is The Nominal Pipe Size of the Run-Pipe. C measures refer to the The Nominal Pipe size of Outlet.
This is actually a redundant designation however, it is derived from the period when t-shirts were sold in 3 different sizes of diameters for example, 4 3 x 2 (A B C). In this case, of course it is imperative to mention 3 different sizes.
This kind of t-shirt is likely to be unavailable. Utilizing a similar tee by using an eccentric or concentric reducer has become the standard procedure.
A straight or even equal buttwelding Tee is offered in all common diameters.
A Reducing Tee does not as certain diameters aren’t produced or cannot be made.
For illustration.. Reduced NPS 6 x 4 tee is a standard product for many suppliers, but an reducing tee NPS 16×2 is likely not offered by any retailer.
It’s also not financially feasible to utilize an NPS 16 Tee with an NPS 2 outlet. In these situations, the Branch Fitting is used or an Branch Connection will be established.
Cross Tee
In addition to the standard tees, there are also stainless straight tees and reduced crosses. Straight crosses are typically standard items, while reducing crosses are typically difficult to locate. I’ve never worn those T-shirts and have never encountered in the real world or at all in the chemical or petro industry. They are likely to be utilized when space is restricted, such as in revisions, in the shipping industries, etc.
Wall Thickness Tee
In the form of a tee, wall thickness is an essential element. ASME B16.9 only defines the end-to-end dimensions, the center-to-end dimension and a few “squareness” tolerances for dimensional measurements.
The thickness of the wall at location of the weld line even has been standardized, but it is not the same throughout the fitting. The standard stipulates that the tolerance must be within 12.5 percent of the required diameter of the wall. A maximum tolerance can be specified only at the end of the pipe.
There are many suppliers of welding Tees (and elbows) offer a different schedule with a larger in thickness to ensure that a sufficient wall thickness, once the wall has been formed the tee, remains. In Tee’s the radius of the crotch (T) differs from one manufacturer to the next and some even establish it as a minimum requirement 1.3 times the thickness of the wall to ensure the crotch is maintained.
…it is anticipated that a part of the fittings that are formed may require a greater thickness that the wall of pipe the fitting intended to be installed.
Since there isn’t any upper limit for certain components in the fittings, the buyer needs to specify what he wants. Based on the specifications of the customer the manufacturer has to confirm that the made tee conforms to the requirements of the client.
You can accomplish this by using additional drawings, along with wall thickness measurements, etc. Verified by an independent third party or by a customer’s inspector.
The additional tests all cost money, and it could be that the cost of these additional tests, much higher than the Tee itself.
