Unlock instant, AI-driven research and patent intelligence for your innovation.

Pipe fitting machining method

A processing method and technology for pipe fittings, which are applied in the direction of pipe components, metal processing equipment, pipes/pipe joints/pipe fittings, etc., can solve the problems of energy consumption, difficult disassembly, and high occurrence rate, and achieve less investment in molds, reasonable structure and simple operation. Effect

Inactive Publication Date: 2014-03-26
BEIJING SHOUHONGGANG HEAVY EQUIP TECH
View PDF7 Cites 15 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] Its disadvantages are: near-end molding cannot be achieved; the incidence of plastic instability is high; there is no inner mandrel system, and the thickening rate of the inner arc section is 1.5-2 times the thinning rate, which is prone to wrinkles; machining after bending is more complicated; Pipe fittings are repeatedly heated to above 950°C, which consumes energy and easily causes grain growth; the mold system is relatively complicated, the manufacturing cost is high, and the process is long, which does not conform to the theory of green manufacturing
[0007] Its disadvantages: it is difficult to guarantee the bending forming technical parameters; cracks are easy to appear during bending deformation; the outer arc section of the molded elbow is more thinning; the manufacturing cost of the huge mold is high, there are many core mold systems, the efficiency is low, and it is difficult to disassemble after bending ; Larger tonnage presses are required, with high cost and high energy consumption

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Pipe fitting machining method
  • Pipe fitting machining method
  • Pipe fitting machining method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0101] Step 1, prepare a TP316LN tube blank with a dimension of Φ965mm×90mm×6650mm, so that the length of the tube blank is left-right symmetrical.

[0102] Step 2: Pre-compensate the above-mentioned tube blank, and process it inside the tube blank, so that the wall thickness of the outer arc section gradually increases from both sides to the bending center, and the thickness of the wall thickness is 11mm. On the contrary, the wall thickness of the inner arc section It gradually decreases from both sides to the bending center, and the wall thickness is reduced by 10.5mm to achieve pre-compensation for wall thickness. The space angle between the inclined nozzle and the vertical plane is 44.5°, and the center distance between the two nozzles is pre-adjusted to 2035mm to realize the pre-compensation of the positions of the two nozzles, such as Figure 7 shown.

[0103] Step 3, preheating the pre-compensated tube blank, and taking the solution heat treatment temperature as 1090°C...

Embodiment 2

[0110] Step 1, prepare a TP316LN tube blank with a dimension of Φ965mm×90mm×6650mm, so that the length of the tube blank is left-right symmetrical.

[0111] Step 2: Pre-compensate the above-mentioned tube blank, and process it outside the tube blank, so that the wall thickness of the outer arc section gradually increases from both sides to the bending center, and the thickness of the wall thickness is 11mm. On the contrary, the wall thickness of the inner arc section It gradually decreases from both sides to the bending center, and the wall thickness is reduced by 9.3mm, which realizes pre-compensation wall thickness. The space angle between the 45° nozzle and the vertical plane is pre-adjusted to 41.9°, and the center distance between the two nozzles is pre-adjusted to 2030mm to realize the pre-compensation of the positions of the two nozzles, such as Figure 8 shown.

[0112] Step 3: Carry out preheating treatment on the tube billet after precompensation treatment, and the ...

Embodiment 3

[0119] Step 1: Prepare a TP316LN tube blank with a dimension of Φ1100mm×100mm×7000mm, so that the length of the tube blank is left-right symmetrical.

[0120] Step 2: Pre-compensate the above-mentioned tube blank, and process it inside the tube blank, so that the wall thickness of the thickening zone gradually increases from both sides to the bending center, and the thickening is 9.7mm. On the contrary, the wall thickness of the thinning zone increases from both sides to the bending center. The lateral bending center gradually decreases, and the thinning is 3.1mm, which realizes the pre-compensation wall thickness. The space angle between the 45° nozzle and the vertical plane is pre-adjusted to 40.3°, and the center distance between the two nozzles is pre-adjusted to 2053mm to realize the pre-compensation of the positions of the two nozzles, such as Figure 9 shown.

[0121] Step 3, the selected solution heat treatment temperature is 1077°C to prevent deformation and surface ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention provides a pipe fitting machining method used for manufacturing a heat pipe section of a main pipeline of a nuclear power station. The pipe fitting machining method comprises the following steps that a pipe blank is manufactured, and the length of the pipe blank is made horizontally symmetrical; pre-compensation is conducted on the pipe blank; the pipe blank formed after pre-compensation is preheated; a bending forming mold is used for conducting one-off press bending forming on the processed pipe blank, so that a pipe fitting is manufactured; the pipe fitting formed after bending forming is machined; solid solution heat treatment is conducted on the machined pipe fitting, and a finished product is manufactured through finish machining finally. By means of the pipe fitting machining method which is a machining method for a nearly-formed pipe fitting, a 100% qualified bent pipe product can be obtained; besides, the process is short, energy consumption is low, mold investment is small, the structure is reasonable, and operation is simple.

Description

technical field [0001] The invention relates to the field of pipe fitting processing, in particular to a pipe fitting processing method for one-time bending forming of a heat pipe section of a nuclear power main pipeline. Background technique [0002] In the pressurized water reactor nuclear power plant, the main pipeline is one of the seven key equipment in the nuclear island, known as the aorta of the nuclear power plant. The main piping connects the reactor pressure vessel, steam generators and reactor coolant pumps. For the first time in the design of the main pipeline, the overall forged 316LN pipe fittings are used, and there is no weld seam. Among them, the processing and forming of the main pipe heat pipe section of AP1000 and CAP1400 is the most difficult point. [0003] The existing forming technologies in China include hot-pressed pipe bending process and cold-pressed pipe bending process. [0004] The hot-pressed pipe bending process refers to pre-processing t...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(China)
IPC IPC(8): B23P15/00B21D37/10F16L43/00
CPCB23P15/00B21D37/10F16L43/001
Inventor 王雅明杜艳梅牟明新金菊荪马晓梅李长田马忠良
Owner BEIJING SHOUHONGGANG HEAVY EQUIP TECH