| 摘要 |
FIELD: machine building. ^ SUBSTANCE: invention refers to pipeline accessories and is designed for implementation in defence industry, at war-ships, in oil and gas producing and chemical industries, at other branches of industry and also in water-, gas-, and heat supply. The valve gate of a welded structure controlled with an off-case drive mechanism consists of a disk-shaped bearing plate and of a flange connecting the valve gate with a pipeline; also the bearing plate and the flange are connected by welding. A boring for a packing washer is made on a lower plane of the disk-shaped bearing plate. Also on an upper plane of the bearing plate there is a boring wherein a bushing welded to the bearing plate is installed. The bushing, the bearing plate and the flange are made with pass-through channels. Their central axes coincide. The bushing is made with a spherical boring serving as a saddle of a ball valve. An external end of the internal lever enters a through rectangular hole in a lug at the upper plane of the ball valve. The internal lever is secured to the centre of the ball valve with a bolt wherein a gap is formed between the bolt head and the upper plane of the lever in vertical direction. When the gate is closed, the counter end of the internal lever is installed in a slot of a drive shaft and is fixed from a spontaneous shifting with its arms and cylinder holders. The drive shaft is arranged in the case of the drive mechanism. The case is welded to the beating plate and to the bushing with a spherical boring. One end of the said case is muffled. The drive shaft with a removable gland seal unit runs through the second end of the case. An opening is made in the case of the drive mechanism to facilitate free rotation of the internal lever in radial direction. Value of this rotation is 90-95. The said opening is made in two horizontal dimensions. One dimension corresponds to the dimension of the internal lever. Another dimension corresponds to the size of that part of the internal lever, which is installed into the slot of the drive shaft so, that there are formed arms of the internal lever to fix the internal lever in the slot of the drive shaft. The internal lever is inserted into the drive shaft slot and is extracted out of it through a bigger dimension of the opening. The middle part of the drive shaft has a bigger diametre equal to internal diametre of the drive mechanism case minus a gap for lubrication. The case of the valve gate is made in form of a pipe section. The lower part of the pipe is welded to the bushing with a spherical boring and to the case of the drive mechanism. The centre of the pipe section is set off relative to the output channels to form a recess to withdraw the valve to open position. ^ EFFECT: increased reliability of shut off of working medium flow along pipelines. ^ 5 dwg |
