CN102189188A - Process for manufacturing seamless stainless steel pipe with large diameter through hot expanding - Google Patents

Abstract

The invention discloses a process for manufacturing a seamless stainless steel pipe with a large diameter through hot expanding. The process mainly comprises the following steps of: arranging a main pipe, a core rod, a connection rod and a tower coil of a hot expanded finished product, namely the stainless steel pipe on an intermediate-frequency hydraulic two-step pushing type pipe expanding unit; uniformly coating high temperature resistant lubricant on the inner wall of the main pipe; allowing the connection rod to pass through the inner hole of the main pipe through a material loading platform, then allowing the connection rod to pass through a rear gate, and an advancing frame gate and reach the tower coil; closing the rear gate, braking the tail end of the connection rod; closing the advancing frame gate to ensure that one end of the main pipe is adhered to the gate tightly; starting the intermediate frequency, heating the core rod and then heating the main pipe to the preset temperature; and starting a hydraulic oil cylinder to ensure that the main pipe advances at constant speed along with an advancing frame, and passes through the reducing part of the core rod. The investment is small, the process is simple, the yield is high, the production group batch is flexible and the cycle is short, the manufacturing cost is low, and the production efficiency can be improved; simultaneously, gas consumption can be greatly reduced, the labor resources are saved, environmental pollution is reduced, the steel pipe has high comprehensive performance, and the tensile strength and the yield strength of the steel are higher than those of the stainless pipe state after the solid solution.

Description

A kind of manufacturing process of hot enlarged diameter gapless stainless steel tube

Technical field

The present invention relates to the manufacturing technology of gapless stainless steel tube, relate in particular to a kind of manufacturing process of hot enlarged diameter gapless stainless steel tube.

Background technology

In modern industry is produced, make the stainless seamless pipe of major diameter with hot-expanding pipe technology and have more reasonability and advance, its characteristics are small investment, operation is simple, the production group is criticized flexibly and the cycle is short, low cost of manufacture, particularly to the stainless seamless pipe of super-large diameter (Φ 600～Φ 1200mm), generally make with cold expansion technology, and with respect to cold expansion technology, make the stainless pipe of super-large diameter with hot-expanding pipe technology and can increase substantially enlarging rate one time, reduce energy resource consumption, reduce the work resource and drop into and environmental pollution, have obvious superiority.Therefore, problems such as operation, lumber recovery, production efficiency can have a strong impact on the manufacturing cost of the cold expansion technology of the stainless pipe of current common manufacturing super-large diameter; In addition, aspect the seamless stainless steel pipe properties of product after required human resources, environmental pollution, cold expansion, tube-surface exists obvious defects.

Summary of the invention

At above defective, the manufacturing process that the purpose of this invention is to provide a kind of hot enlarged diameter gapless stainless steel tube, by adopting intermediate frequency hydraulic pressure two step pushing formula pipe expanding set, change original plug, coil structure structure, select at the uniform velocity pushing under the condition of proper lubrication agent and temperature and fltting speed for use, thereby realize the purpose of seamless stainless pipe hole enlargement; Use the hole enlargement continuously of this technology simultaneously, do not need intermediate annealing, defective such as non-microcracked produces.

For achieving the above object, the present invention is achieved through the following technical solutions:

A kind of manufacturing process of hot enlarged diameter gapless stainless steel tube mainly may further comprise the steps:

(1) selects to be fit to mother's pipe that heat expands the finished product stainless steel tube, plug, connecting rod and turriform coil, and be installed on the intermediate frequency hydraulic pressure two step pushing formula pipe expanding set, turriform coil encircling mother Yu wherein manages the periphery, plug places in female pipe, this unit bottom is provided with the pipe expanding set support, on this pipe expanding set support late gate and bearing are installed, oil cylinder, mobile advance frame and preceding bearing, described mobile advance frame rear and front end is separately installed with and connects the advance frame gate, oil cylinder is fixed in the late gate bearing and is connected with advance frame, and connecting rod one end fixedly passes the advance frame gate through late gate and is connected with preceding bearing and with plug;

(2) adopt the plug zone to be provided with, described plug is confessed one's crime to setting gradually to the end and is divided into Lead-In Area, deformed area, sizing area, clear area and aligning district, connecting rod connect with Lead-In Area and the assurance concentricity consistent, the connecting rod diameter is slightly less than the Lead-In Area diameter; The diameter of bore of turriform coil entrance and exit is respectively than mother's pipe and the big 3-8cm of production tube external diameter, and the expander temperature determines that according to stainless tubing matter fltting speed is determined according to the wall thickness and the reducing rate size of female pipe;

(3) pre-prepd female pipe inside pipe wall is evenly coated fire-resistant lubricants, by feeding platform connecting rod is passed female pipe orifice, female pipe process late gate, advance frame gate are to the turriform coil, close late gate, lock is lived the connecting rod tail end, close the advance frame gate, make female Guan Yiduan be close to gate, startup intermediate frequency elder generation heating plug heats female pipe again makes female pipe to predetermined temperature, restart hydraulic jack, under the effect of oil cylinder, female pipe is at the uniform velocity advanced with advance frame, through plug reducing place, thereby realize stainless pipe hole enlargement purpose.

The beneficial effect of the manufacturing process of hot enlarged diameter gapless stainless steel tube of the present invention is: applicable to the stainless seamless pipe of major diameter (Φ 600～Φ 1200mm), for manufacturing process such as hot rolling, hot extrusion, forging, this process equipment less investment, operation is simple, lumber recovery is high, the production group is criticized flexibly and the cycle is short, low cost of manufacture, particularly the current cold expansion technology of generally making the stainless pipe of major diameter is compared, can enhance productivity more than 5 times; Simultaneously, reconditioning in the middle of not needing, annealing, pickling, passivation can reduce gas consumption in a large number, save human resources, reduce environmental pollution, the high comprehensive performance of the seamless stainless steel pipe after heat expands, its tensile strength, yield strength obviously are better than the stainless tubulose attitude after the solid solution.

Description of drawings

According to embodiment and accompanying drawing the present invention is described in further detail below.

Fig. 1 is the intermediate frequency hydraulic pressure two step pushing formula pipe expanding set structural representations that the embodiment of the invention adopts;

Fig. 2 is the mandrel structure schematic diagram that the embodiment of the invention adopts.

Among the figure:

1, pipe expanding set support; 2, feeding platform; 3, oil cylinder; 4, late gate and bearing; 5, mobile advance frame; 6, connecting rod; 7, coil; 8, plug; 9, advance frame gate; 10, discharging bearing; 11, coil support; 12, preceding bearing; 81, Lead-In Area; 82, deformed area; 83, sizing area; 84, clear area; 85, aligning district.

The specific embodiment

As shown in Figure 1, the manufacturing process of hot enlarged diameter gapless stainless steel tube of the present invention, its key step comprises:

(1) selects to be fit to mother's pipe that heat expands the finished product stainless steel tube, plug 8, connecting rod 6 and turriform coil 7, and be installed on the intermediate frequency hydraulic pressure two step pushing formula pipe expanding set, carrying out technology when being provided with, it is peripheral that turriform coil 7 wherein is surrounded on female pipe, the built-in plug 8 of female pipe, this unit bottom is provided with pipe expanding set support 1, mobile advance frame 5 is installed on this pipe expanding set support 1, described mobile advance frame 5 two ends are separately installed with advance frame gate 9 and preceding bearing 12 and late gate and bearing 4, wherein connecting rod 6 is through late gate and bearing 4 and pass mobile advance frame gate 9 and be connected plug 8 with preceding bearing 12, late gate wherein and bearing 4 outer setting feeding platforms 2 and oil cylinder 3, oil cylinder 3 connects advance frame 5, wherein connecting rod 6, plug 8 and turriform coil 7 are replaceable, and plug 8 is installed discharging bearing 10 respectively with turriform coil 7 belows, coil support 11;

(2) described plug 8 is confessed one's crime to setting gradually to the end and is divided into Lead-In Area 81, deformed area 82, sizing area 83, clear area 84 and aligning district 85, sizing area 83 diameters+2 (female thickness of pipe wall-wall thickness reducing amount) wherein are the production tube wall thickness, production tube length is the female length of tube of (female external diameter of pipe/production tube external diameter+0.04) *, Lead-In Area 81 diameters should be less than more than female bore 3cm, connecting rod 6 connects with Lead-In Area 81 and guarantees that concentricity is consistent, and connecting rod 6 diameters are slightly less than Lead-In Area 81 diameters; The diameter of bore of turriform coil 7 entrance and exits is respectively than mother's pipe and the big 3-8cm of production tube external diameter, thereby make female pipe be easy to heat up and be in optimum state, and high-temperature lubricant should dispose its denseness according to the wall thickness of female pipe, the thick more denseness of wall thickness is high more, the expander temperature determines that according to different stainless tubing matter fltting speed is determined according to the wall thickness and the reducing rate size of female pipe;

(3) pre-prepd female pipe inside pipe wall is evenly coated high temperature resistant lubricant agent special, by feeding platform 2 connecting rod 6 is passed female pipe orifice, female pipe process late gate 4, advance frame gate 9 and preceding bearing 12 are to turriform coil 7, close late gate 4, lock is lived connecting rod 6 tail ends, close advance frame gate 9, make female Guan Yiduan be close to gate, startup intermediate frequency elder generation heating plug 8 heats female pipe again makes female pipe to predetermined temperature, restart hydraulic jack 3, under the effect of oil cylinder 3, female pipe is at the uniform velocity advanced with advance frame, pass through plug 8 reducing places, thereby realize the purpose of stainless pipe hole enlargement.

Claims (1)

1. the manufacturing process of a hot enlarged diameter gapless stainless steel tube is characterized in that, mainly may further comprise the steps:

(1) selects to be fit to mother's pipe that heat expands the finished product stainless steel tube, plug, connecting rod and turriform coil, and be installed on the intermediate frequency hydraulic pressure two step pushing formula pipe expanding set, turriform coil encircling mother Yu wherein manages the periphery, plug places in female pipe, this unit bottom is provided with the pipe expanding set support, on this pipe expanding set support late gate and bearing are installed, oil cylinder, mobile advance frame and preceding bearing, described mobile advance frame rear and front end is separately installed with and connects the advance frame gate, oil cylinder is fixed in the late gate bearing and is connected with advance frame, and connecting rod one end fixedly passes the advance frame gate through late gate and is connected with preceding bearing and with plug;

(2) adopt the plug zone to be provided with, described plug is confessed one's crime to setting gradually to the end and is divided into Lead-In Area, deformed area, sizing area, clear area and aligning district, connecting rod connect with Lead-In Area and the assurance concentricity consistent, the connecting rod diameter is slightly less than the Lead-In Area diameter; The diameter of bore of turriform coil entrance and exit is respectively than mother's pipe and the big 3-8cm of production tube external diameter, and the expander temperature determines that according to stainless tubing matter fltting speed is determined according to the wall thickness and the reducing rate size of female pipe;

(3) pre-prepd female pipe inside pipe wall is evenly coated fire-resistant lubricants, by feeding platform connecting rod is passed female pipe orifice, female pipe process late gate, advance frame gate are to the turriform coil, close late gate, lock is lived the connecting rod tail end, close the advance frame gate, make female Guan Yiduan be close to gate, startup intermediate frequency elder generation heating plug heats female pipe again makes female pipe to predetermined temperature, restart hydraulic jack, under the effect of oil cylinder, female pipe is at the uniform velocity advanced with advance frame, through plug reducing place, thereby realize stainless pipe hole enlargement purpose.

Images