RADIAL-END GAS DYNAMIC SEAL OF TURBO MACHINES ROTORS SUPPORTS OIL CAVITY Russian patent published in 2017 - IPC F02C7/28 F16J15/34 

FIELD: machine building.

SUBSTANCE: radial-end gas dynamic seal of turbomachines rotors supports oil cavity, containing support oil cavity cover, made from magnesium or titanium alloy, arranged in it: gas dynamic seal, sealing support oil cavity, comprising gas-dynamic sealing housing, fixed in support oil cavity cover, non-rotating split sealing ring movable in axial direction, pressed by air pressure, or air pressure and springs, or by spring to shaft mounted rotary bushing, on working face of which spiral gas dynamic chambers are made, and contacting with gas-dynamic sealing housing by cylindrical surface, to which it is pressed by this ring elastic forces and air pressure in support pre-oil cavity, labyrinth seal, sealing support pre-oil cavity, formed by labyrinth ring fixed on shaft, and labyrinth seal housing fixed in oil cavity cover with sealing insert from depleting material fixed in it, and both seals joints with support oil cavity cover are packed by rubber sealing rings. Split sealing ring is made with radial cut with width of more than 100 mqm. Cut width is made such, that provides joint leak-tightness and absence of split sealing ring direct contact with rotary bushing in all turbine machine operating conditions with speed, exceeding 500 rpm. Gap in sealing ring cut remains completely used under all turbomachine operating conditions. In rotary bushing through holes are made, connecting gap between rotary bushing ends and sealing ring with oil bath, formed by flanging, made on rotary bushing other end, equally arranged along circumference between spiral chambers or directly in spiral chambers. Split sealing ring is made of bronze BrS30, and gas dynamic seal housing is from steel with close thermal linear expansion factor. Labyrinth seal housing is made from steel with thermal linear expansion factor value close to titanium alloy, and labyrinth ring is made from steel with thermal linear expansion factor value close to shaft steel. Between the pins and mating holes in both seals housings there is gap, preventing dangerous contact between pins and these holes walls at thermal expansion of these parts, and resilient washers rigidity is selected so, that at their complete straightening at self-locking nuts tightening friction forces are created on their contact surfaces, overcomable at thermal expansion of these parts without occurrence of dangerous tensions in them and compellent under action of working bending moments on split sealing ring.

EFFECT: enabling sealing higher efficiency and service life at sealed medium increased temperature.

3 cl, 7 dwg