Abstract: A valve for intercepting a fluid in a duct is provided. The valve has a valve body, a ball shutter, and a sealing device for forming a fluid seal with an external surface of the ball shutter. The sealing device has a polymeric sealing ring located in contact with the external surface, and a metal support ring coupled to the sealing ring. The support ring has an annular coupling portion having an annular contact portion formed by a frustoconical wall, and an elastically bendable influencing portion, so as to form an elastic lever. In an emergency condition in which the sealing ring is absent the annular contact portion is in contact with the external surface of the ball shutter due to at least fluid pressure, forming the fluid seal even in the emergency condition.

Abstract: An apparatus for bending and/or curving tubes or bars, comprises bearings for the tube or bar to be curved or bent. The said bearings arranged on a support having a handle extending therefrom and enclosing an axially movable stem. A fluid, which is furnished by a pump being enclosed within a container for the collection of the tool operating fluid in a closed circuit also passing continuously through said handle, the flowing speed of said fluid being adjustable by means of a throttling member. The resulting increase in fluid pressure, as built up upstream of the throttling, being used for a stem feeding pressure, with subsequent bending and/or curving operation.