DEVICE TO SHUTOFF BEND CAVITY Russian patent published in 2014 - IPC F16L55/12 F16L55/16 F16L55/18 

FIELD: machine building.

SUBSTANCE: device comprises a chamber sealed in relation to a movable rod coming into it, a drive unit and a sealing unit introduced into the bend cavity. The sealing unit comprises an elastic cup, a support disk with expanding elements and an upper turning flange set on it. The expanding elements are made as circular segments with ribs and recesses which are overlapping each other and are shifted so that they form a compound flat disk when put together. The segments are equipped by a pin in the upper part and a protrusion in the lower part. The segments are engaged with screw grooves in the form of Archimedean spiral part on the upper turning flange by means of the pins. At turning of the flange the expanding elements move in the radial direction along the grooves on the support disk in which protrusions are inserted, and press the elastic cup to the bend walls. A holding unit in the form of a cross member with retainer bars is mounted on the bend flange and rests against a ring fixed on the holding unit.

EFFECT: reliable fixation of the device without creating obstacles to pumped product, and sealing along the whole bend perimeter.

7 dwg