Stainless steel investment steel pipe transition fittings crosses

Stainless steel investment steel pipe transition fittings crosses

Crosses, also known as four-way fittings or cross branch lines, have one inlet and three outlets (or vice versa), and often have solvent-welded socket or female-threaded ends. 

Cross fittings may stress pipes as temperatures change, because they are at the center of four connection points. 

A tee is steadier than a cross; it behaves like a three-legged stool, and a cross behaves like a four-legged stool. 

Geometrically, any three non-collinear points can self-consistently define a plane; three legs are inherently stable, whereas four points overdetermine a plane, and can be inconsistent, resulting in physical stress on a fitting.

Crosses are common in fire sprinkler systems (where stress caused by thermal expansion is not generally an issue), but are not common in plumbing. 

One cross fitting is more expensive than two tees.

Drawing