Flexible manufacturing development of the hottest

  • Detail

Abstract: through the design and manufacture of special tooling and the development of numerical control program, the Ingersoll numerical control boring and milling machine is used to process the high and medium pressure outer cylinder and valve components, expand the processing scope and capacity of the machine, enhance the flexibility of the company's cylinder processing technology, realize the resource optimization of key numerical control equipment, and provide convenience for production planning management

key words: high and medium pressure outer cylinder; CNC boring and milling machine; Tool interface design; NC programming

0 introduction

with the recovery of the power station market, STC currently undertakes orders totaling 40million kW. The enterprise will have an equivalent of more than 7million kW in 2003 and an annual production capacity of more than 10million kW in 2004. How to seize market opportunities, meet customer needs, make full use of existing resources, optimize resource allocation, and quickly improve the manufacturing capacity and level of enterprises has become an important factor for enterprises to achieve leapfrog development in the next stage

stc's only high-precision CNC gantry milling imported from Germany has been mainly responsible for the processing of high and medium pressure outer cylinders of high-power units. With the increase of the number of enterprise orders and the proportion of high-power units, the number of high and medium pressure outer cylinders that need to be processed has increased significantly. NC gantry milling completed 16 cylinders in 2001, 33 in 2002, and more than 50 cylinders are planned to be completed in 2003. NC gantry milling processing high and medium pressure outer cylinders has become the "bottleneck" of production. In another Ingersoll NC boring and milling machine purchased by STC, due to the limitation of the processing range of the equipment, it was initially mainly used to share the processing task of the INNSE NC boring and milling machine and undertake the processing of the low-pressure outer cylinder. Its production task has not been very full, and only two shifts of production are opened. In order to dredge the bottleneck, we chose to tackle key problems through technology, develop the processing capacity of high and medium pressure outer cylinders on Ingersoll CNC boring and milling machine, share the production "bottleneck" of CNC gantry milling, increase the "flexibility" of manufacturing process, and give full play to existing resources

1 current situation and existing problems of machine tools

ingersoll CNC boring and milling machine was initially purchased with only two straight milling heads and two corner square milling head accessories, of which one corner square milling head is dedicated to the machining of large diameter spherical surfaces. The machine tool mainly undertakes the processing of low-pressure outer cylinder. Recently, five axis linkage universal milling head and flower plate milling head have been added, and the function of the machine tool has been greatly increased. Through technological research, new processing methods and NC processing programs have been developed for various milling heads, so that they can process high and medium pressure outer cylinders

through the investigation and analysis of the current situation of the equipment, to process the high and medium pressure outer cylinder on the Ingersoll NC boring and milling machine, two major problems need to be solved:

(1) the auxiliary tooling of the machine tool is insufficient

(2) the original processing program should be parameterized, and new processing programs should be developed for new accessories to fully develop their functions

2 process plan and implementation

2.1 determination of the interface size of the pull pin and conversion row

based on the sales of accessories, the major CNC machine tool manufacturers in the world, such as Ingersoll, INNSE, waldr ishcoburg, cscem, etc., adopt their own spindle and accessory shaft interface standards, so that the CNC machine tool tools of our company cannot be directly interchanged. Ingersoll CNC boring and milling machine interface adopts short shank Gala nail structure. According to the interface size provided by Ingersoll company, we designed a special pull pin structure and ordered it from a tool factory in Shanghai

for Ingersoll CNC boring and milling machine, except for the special disc accessories ordered for the 6:1 disc, the other accessory shafts adopt different short shank forms, among which the 4:1 straight milling head and 2:1 straight milling head affect the accuracy of the experimental data. The head and 3:1 square milling head adopt din60 standard, the 1:1 square milling head adopts din2079 standard (special for machining spherical surface), and the 3:1 universal milling head adopts din69871 standard. We have successively designed and manufactured the conversion row of din60/Mozi No. 3, din60/Mozi No. 4, din60/Mozi No. 5, din60/Mozi No. 6, din60/iso50, din69871/Mozi No. 3, din69871/Mozi No. 4, din69871/Mozi No. 5, din69871/Mozi No. 6, din69871/din60, din69871/iso50 and other specifications, realizing the clamping of various cutting tools and improving the process interchangeability between different types of key NC machine tools

2.2 preparation of parametric subroutines

in order to reduce programming workload and ensure correct processing, we have adopted the idea of parametric programming and compiled five special subroutines. Parametric programming is to realize the processing of the same type of processing mode with the help of parameter assignment in the program, so as to simplify the program and facilitate operation. We have successively compiled the Confucius program o302, the reverse scraping subroutine o9015, the reverse boring subroutine o9016, the three-axis linkage milling thread subroutine o666, and the three-axis linkage milling inner Confucius program o667

2.3 add the mathematical model analysis and programming of the five axis machining of the universal milling head

Figure 3 Analysis of the five axis machining model of the universal milling head

from Figure 3, it can be seen that through the superposition and rotation function of the B and C axis coordinate system of the universal milling head, the X, y, Z, B, C five axis machining can be realized, which greatly facilitates the machining of the plane and hole of the space inclined flange, It solves the problem of repeatedly clamping the cylinder when machining the inclined flange plane and inclined hole of the intermediate pressure outer cylinder of subcritical 600MW steam turbine

the following is the research and development of Wan, which will also provide inexhaustible development momentum for the extruder industry. Examples of five axis NC machining programs for milling heads:

n5 m92 t

n10 G0 g54 b123.75 c39.745 S60 F5 m86

n15 g19

n20 g68 x0 Y0 Z0 I0 J1 K0 r-5

n25 G0 X400 Y0 z0

n35 G0 x600

n40 g69

n45 m5

2.4 preparation of NC processing program for newly added accessory flower disc

flower disc It is mainly used for the processing of inner holes such as steam inlet, steam extraction port and valve of high and medium pressure outer cylinder and the processing of external profile of welding groove. Use AutoCAD or UG software to draw the inner hole and the external profile of the welding groove when the load is stable until the end of the pressure holding time, and then generate coordinate data files. The relative coordinate system is realized by G instruction G91, and the profile machining can be realized by introducing the data file into the relative coordinate system

Figure 4 flower plate processing schematic diagram

the following are examples of 18 new material processing programs found by the developed flower plate CNC:


n5 m92 t

n10 G0 g54 G94 g98 G90 M86 C0 S60 z100

n15 x0 Y0 Z5 m3

n20 G18 u-4

n25 G1 z0

n35 G1 U1 z-10

n40 G1 z-167

n45 z-26 u1.4

n50 G0 G90 z100

n55 m5

3 actual effect

Through the design, development and manufacture of special tooling such as pushpin and conversion row on Ingersoll NC boring and milling machine, the five axis linkage is realized by using the b-axis and c-axis coordinate system superposition and rotation function of the universal milling head of the machine tool, and the NC program is developed in combination with the cam function of AutoCAD and UG. The machining of high and medium pressure outer cylinders and valves with Ingersoll NC boring and milling machine is successfully realized. The accumulated working hours of Ingersoll CNC boring and milling machine in 2002 increased by 34.94% on the basis of 2001. The working hours completed from January to June 2003 increased by 20.23% year-on-year, realizing full load production and greatly alleviating the "bottleneck" of CNC gantry milling; At the same time, it makes full use of the company's key equipment, improves the flexibility of the process, facilitates production planning management, and reduces the manufacturing cost of products

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