Abstract: In a preferred embodiment, a fluid flow valve, including: an elongate body having an axially extending cavity defined therethrough and having fluid inlet and outlet ports; a hollow seat assembly disposed in the body for the passage therethrough of a fluid; a shaped first aperture defined through a wall portion of the seat assembly; and a plug selectively axially moveable in the hollow seat assembly and along the shaped first aperture such that the fluid flows into the hollow seat assembly, upwards past the plug into the first aperture, through the first aperture, downwards past the plug, and out of the hollow seat assembly, the position of the plug along the aperture determining rate of flow of the fluid through the valve.

Abstract: In a preferred embodiment, a method and apparatus for forming thin-wall tubing for later welding of the seam thereof which includes tightly rolling upon itself a sheet of thin metal stock about a roller between layers of a flexible fabric. When released from the roller, the sheet metal springs back to form a near-perfect tube without the kinks, scratches, and/or dents commonly caused by conventional rolling methods.