Rolling-bulging forming hydraulic machine for tubular products

A rolling-bulging forming hydraulic machine for tubular products, comprising a frame, wherein the frame is provided with an upper rolling block, a lower rolling block, a fixed liquid bulging hydraulic cylinder and a movable liquid bulging hydraulic cylinder;

• the upper rolling block and the lower rolling block are arranged oppositely;
• the upper rolling block is configured to roll an upper surface of a to-be-machined tubular product;
• the lower rolling block is configured to roll a lower surface of the to-be-machined tubular product;
• the fixed liquid bulging hydraulic cylinder and the movable liquid bulging hydraulic cylinder are arranged oppositely, and the fixed liquid bulging hydraulic cylinder and the movable liquid bulging hydraulic cylinder are configured to charge hydraulic oil into the to-be-machined tubular product to perform hydraulic bulging on the to-be-machined tubular product;
• the frame comprises a plurality of stand columns, an upper crossbeam, a lower crossbeam, a middle fixed beam and a hydraulic cylinder motion guide rail;
• the upper crossbeam is fixedly connected with the upper ends of the plurality of stand columns;
• the lower crossbeam is fixedly connected with the lower ends of the plurality of stand columns;
• the middle fixed beam is fixedly connected with the stand columns through two locking nuts;
• and the hydraulic cylinder motion guide rail is fixedly connected with the stand columns;
• the upper rolling block is arranged on the upper crossbeam;
• the lower rolling block is arranged on the lower crossbeam;
• the fixed liquid bulging hydraulic cylinder is fixedly arranged on the middle fixed beam;
• and the movable liquid bulging hydraulic cylinder is slidably connected with the hydraulic cylinder motion guide rail;
• the upper crossbeam is fixedly connected with an upper movable crossbeam guide rail;
• the upper movable crossbeam guide rail is slidably connected with an upper movable crossbeam inner slide block;
• a first side of the upper movable crossbeam inner slide block is fixedly connected with a plunger of an upper main motion cylinder;
• the upper rolling block is fixed at a second side of the upper movable crossbeam inner slide block;
• the lower crossbeam comprises a lower movable crossbeam guide rail and a lower movable crossbeam inner slide block;
• the lower movable crossbeam guide rail and the lower movable crossbeam inner slide block are slidably connected;
• a first side of the lower movable crossbeam inner slide block is fixedly connected with a plunger of a lower main motion cylinder;
• and the lower rolling block is fixed at a second side of the lower movable crossbeam inner slide block;
• the plunger of the upper main motion cylinder is configured to drive the upper movable crossbeam inner slide block to slide along the upper movable crossbeam guide rail to drive the upper rolling block to move along an axial direction of the to-be-machined tubular product, so as to roll the upper surface of the to-be-machined tubular product;
• the plunger of the lower main motion cylinder is configured to drive the lower movable crossbeam inner slide block to slide along the lower movable crossbeam guide rail to drive the lower rolling block to move along the axial direction of the to-be-machined tubular product, so as to roll the lower surface of the to-be-machined tubular product;
• wherein the fixed liquid bulging hydraulic cylinder and the movable liquid bulging hydraulic cylinder have the same structure;
• each of the fixed liquid bulging hydraulic cylinder and the movable liquid bulging hydraulic cylinder comprises a piston rod, a piston, a ball bearing, a bulging head, a cylinder barrel set, a gland, a cylinder cover, a guide sleeve and a flange;
• the guide sleeve is connected with the cylinder barrel set;
• a main body portion of the guide sleeve is arranged in the cylinder barrel set;
• the gland seals a first end of the cylinder barrel set;
• the outer end of the gland is connected with the flange;
• the cylinder cover seals a second end of the cylinder barrel set;
• the ball bearing is embedded inside the cylinder cover;
• the bulging head is inserted into the ball bearing;
• the bulging head is fixed axially with respect to the ball bearing;
• the bulging head rotates on a common axis with the ball bearing;
• the piston is arranged in the cylinder barrel set and located between the guide sleeve and the gland;
• a first end of the piston rod is inserted in the cylinder cover, and a second end of the piston rod passes through the guide sleeve, the piston, the gland and the flange in sequence to extend out of the cylinder barrel set;
• the side portion of the flange is provided with a first oil inlet;
• an oil pool is arranged inside the flange;
• the piston rod is provided with a second oil inlet;
• a first oil passage is arranged axially in the piston rod;
• the first oil passage communicates with the second oil inlet;
• the hydraulic oil enters the oil pool through the first oil inlet and then enters the first oil passage through the second oil inlet;
• the cylinder cover is internally and axially provided with a second oil passage, and the bulging head is internally and axially provided with a third oil passage;
• the second oil passage communicates with the third oil passage;
• the second oil passage and the third passage communicate with the first oil passage;
• the hydraulic oil enters the first oil passage so as to be charged into the to-be-machined tubular product through the second oil passage and the third oil passage to provide internal pressure to perform internal hydraulic bulging;
• and the side portion of the cylinder barrel set is provided with a third oil inlet, thereby providing mechanical energy to a reciprocating rectilinear movement of the piston rod;
• and
• the bulging head at a front end of the fixed liquid bulging hydraulic cylinder stretches into a first end of the to-be-machined tubular product;
• the bulging head at a front end of the movable liquid bulging hydraulic cylinder stretches into a second end of the to-be-machined tubular product;
• and sealing elements are arranged respectively between the to-be-machined tubular product and the bulging head at the front end of the fixed liquid bulging hydraulic cylinder and the bulging head at the front end of the movable liquid bulging hydraulic cylinder.