Machining method for digitally measuring and guiding large impact type branch pipe

Abstract

The invention discloses a processing method for guiding a large impact type branch pipe through digital measurement. The processing method comprises the following steps that 1, a ground sample line is detected and corrected through digital measurement; 2, digitally measuring and detecting branch pipe inlet and outlet surfaces and a flange surface processing line; 3, judging the detection data model by adopting a digital analysis technology; and step 4, arranging, aligning, processing and detecting the branch pipe based on the rotary table. The scribing precision is quickly judged based on advanced digital measurement and data model analysis technologies; a special tool clamp is designed based on the structural process characteristics of the branch pipe and the specific parameters of machining equipment, and the requirement for machining the branch pipe on a rotating table is met; correcting the alignment deviation before processing by adopting a digital analysis technology; and after machining is completed, the machining feature surface is subjected to rapid digital measurement, and data model judgment is carried out. The consistency and the accuracy of lineation data, alignment data and processing data are realized, and the reliability, the accuracy and the high efficiency of processing are improved.

Description

Technical Field

[0001] The invention relates to the technical field of large-scale impulse turbines, in particular to a processing method for digitally measuring and guiding large-scale impulse bifurcated pipes. Background Art

[0002] The water distribution ring pipe of large-scale impulse turbine units is required to be assembled as a whole in the factory and marked with necessary matching marks. As the key and core component of the water distribution ring pipe, the branch pipe is the reference part for the overall pre-installation measurement of the water distribution ring pipe. Its processing accuracy directly affects the repair efficiency of the paired straight pipe section and the quality of the overall pre-installation of the water distribution ring pipe. The inlet and outlet surfaces and flange surfaces of the branch pipe of a large impulse turbine must be processed. Due to its large structural size, heavy weight, large processing area, and large thin-walled parts, the processing process is poor and the processing quality risk is high. It is urgent to develop a new processing method to improve the accuracy of processing.

[0003] Existing technical solutions include the following methods: using manual marking and hanging lines to draw the branch pipe ground sample line, horizontal center line, processing lines and sight lines of each mouth surface; using the horizontal center line to level on the fixed workbench of a large boring machine, using the processing line to align the workpiece, and using milling to process the flange and the inlet and outlet surfaces. However, there are the following problems: 1) Poor accuracy: using manual marking of ground sample lines and branch pipe processing lines, the error is large; the processing completely relies on the marking reference for alignment, and the alignment deviation is large. The two errors are accumulated, resulting in poor final processing accuracy of the branch pipe, which cannot meet the overall pre-installation requirements of the water distribution ring pipe. 2) Uncontrollable quality: There is no reliable detection method after marking, alignment and processing, and the process quality cannot be ensured. 3) Low efficiency: Processing on a fixed platform, the branch pipe must be re-clamped, aligned and fixed after transfer, which is inefficient. Summary of the invention

[0004] The purpose of the present invention is to provide a digital measurement and guidance processing method for large impact type bifurcated pipes in order to solve the above-mentioned problems, which has high precision, reliable quality and high production efficiency.

[0005] The technical solution adopted by the present invention is as follows:

[0006] A method for processing a large impact bifurcated pipe by digital measurement and guidance, comprising the following steps:

[0007] Step 1: Digitally measure and detect the corrected ground sample line;

[0008] Step 2: Digitally measure and inspect the inlet and outlet surfaces of the bifurcated pipe and the flange surface processing line;

[0009] Step 3: Using digital analysis technology to determine the detection data model;

[0010] Step 4: Layout, alignment, processing and inspection of branch pipes based on the rotary table.

[0011] Optionally, in step 1, a laser tracker probe is used to locate and detect, analyze the accuracy of manual marking of the ground sample, and make corrections.

[0012] Optional, ensure that the overall ground sample marking deviation is within 1mm.

[0013] Optionally, in step 2, after the processing lines of the inlet and outlet surfaces and the flange surface of the branch pipe are marked by hanging wires and laser projection, a laser tracker is used to detect the marked processing lines.

[0014] Optionally, in step 3, the measured data model is digitally analyzed, and the measured data model is matched with the theoretical data model to determine whether the processing line accuracy of the inlet and outlet surfaces and the flange surface meets the requirements.

[0015] Optionally, in step 4, based on the structural process characteristics of the branch pipe and the specific parameters of the processing equipment, a special tooling fixture is designed to meet the requirements of branch pipe processing on a rotary table.

[0016] Optionally, in step 4, the flange surface must be aligned on the machine tool in accordance with the trend of the model data comparison in step 3.

[0017] Optionally, in step 4, after the alignment meets the requirements, the flange surface and the inlet and outlet surfaces are milled in sequence on the rotary table, and the processing parameters are optimized through trial processing.

[0018] Optionally, in step 4, digital measurement is used to detect each processed surface after processing.

[0019] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0020] The present invention provides a processing method for a large impact bifurcated pipe guided by digital measurement. The method quickly determines the marking accuracy based on advanced digital measurement and data model analysis technology. Based on the structural process characteristics of the bifurcated pipe and the specific parameters of the processing equipment, a special tooling fixture is designed to meet the requirements of bifurcated pipe processing on a rotary table. The digital analysis technology is used to correct the alignment deviation before processing. After processing, the processing feature surface is quickly digitally measured and the data model is determined. The consistency and accuracy of the marking data, alignment data and processing data are achieved, and the reliability, accuracy and efficiency of the processing are improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The present invention will now be described by way of example with reference to the accompanying drawings, in which:

[0022] Figure 1 It is a flow chart of the present invention.

[0023] Figure 2It is a structural schematic diagram of the branch pipe being fixed on the workbench. DETAILED DESCRIPTION

[0024] The present invention will be described in detail below in conjunction with the accompanying drawings.

[0025] All features disclosed in this specification, or steps in all methods or processes disclosed, except mutually exclusive features and / or steps, can be combined in any manner.

[0026] Any feature disclosed in this specification, unless otherwise stated, can be replaced by other equivalent or alternative features with similar purposes. That is, unless otherwise stated, each feature is only an example of a series of equivalent or similar features.

[0027] A digital measurement and guidance processing method for large impact bifurcated pipes, such as Figure 1 As shown, the following steps are included:

[0028] Step 1: Digitally measure and detect the corrected ground sample line;

[0029] Step 2: Digitally measure and inspect the inlet and outlet surfaces of the bifurcated pipe and the flange surface processing line;

[0030] Step 3: Using digital analysis technology to determine the detection data model;

[0031] Step 4: Figure 2 As shown, the branch pipe layout, alignment, processing and inspection are based on the rotary worktable.

[0032] In step 1, the ground sample line refers to the reference line drawn on the ground where the workpiece or equipment is installed according to the design drawings. These lines are an important basis for guiding subsequent processing, assembly and positioning, ensuring that the installation position of the workpiece or equipment is accurate. Establish a measurement control system in the bifurcated pipe placement area to ensure a stable environment. Use digital measuring equipment to scan the bifurcated pipe ground sample line to obtain three-dimensional coordinate data. Compare the measured data with the design model and use professional software to correct the ground sample line. Provide an accurate reference line for subsequent processing and assembly. By comparing with the design model, the deviation of the ground sample line is discovered and corrected.

[0033] In step 2, digital measuring equipment is used to scan and detect the processing lines of the inlet and outlet surfaces and flange surfaces before and after the bifurcated pipe is processed. The actual position data of the processing line is obtained through software analysis. The deviation of the processing line is determined by comparing with the design data. It is ensured that the position and shape of the processing surface meet the design requirements. It provides accurate positioning data for processing, improves the processing accuracy of the processing surface, and reduces the errors caused by manual measurement and marking.

[0034] In step 3, the software is used to process the measured data and establish an accurate digital model. The model is analyzed for errors to determine whether the accuracy of the processing line meets the design requirements. The processing strategy is adjusted according to the analysis results to optimize the processing path. It is determined whether there is a deviation in the processing process, as well as the size and direction of the deviation. This provides a basis for subsequent processing adjustments, realizes real-time monitoring and control of processing quality, and improves the quality controllability of the processing process.

[0035] In step 4, fix the branch pipe on a workbench with a rotary function. Using a workbench with a rotary function, the branch pipe can be processed and inspected at different angles. Using digital measurement data, the CNC system automatically aligns the workpiece position. The CNC milling process is started during the processing, and the flange and inlet and outlet surfaces are processed according to the optimized processing path. During the processing, the processing data is monitored in real time to ensure the processing accuracy. Inspection and correction After the processing is completed, the digital measuring equipment is used again to inspect the processed surface. Compare the processing data with the design model. If there is a deviation, make necessary corrections. The processing efficiency is improved and the time for re-clamping and alignment after transfer is reduced. The rotary table can achieve continuous processing at multiple angles and multiple stations, greatly improving the degree of processing automation.

[0036] As another specific implementation, in step 1, a laser tracker probe is used to locate, detect, and analyze the accuracy of manual marking of the ground sample, and make corrections. According to the position of the ground sample line, the probe is used to touch the key points on the manually marked ground sample line point by point. The laser tracker records the three-dimensional coordinates of each point. The measured three-dimensional coordinate data is input into professional analysis software. The actual measurement data is compared with the ground sample line data in the design model. The analysis software will display the deviation between the actual position and the design position of the ground sample line. According to the analysis results, determine where corrections are needed. Use the measurement data as a reference to re-mark or adjust the ground sample line to ensure that it is consistent with the design model. The laser tracker has a very high measurement accuracy, which is much higher than manual marking. Through high-precision measurement, the errors caused by manual marking can be significantly reduced. And the laser tracker can display the measurement data in real time, so that the correction of the ground sample line can be carried out immediately without waiting.

[0037] As another specific implementation, the overall ground sample line deviation is ensured to be within 1 mm. The ground sample line serves as a reference for subsequent processing and assembly, and its accuracy directly affects the assembly accuracy of the entire system. Deviations within 1 mm can significantly reduce the cumulative errors in multiple components and processing steps.

[0038] As another specific implementation, in step 2, after the processing lines of the inlet and outlet surfaces and the flange surfaces of the branch pipe are marked by hanging wires and laser projection, a laser tracker is used to detect the marked processing lines. Specifically, a hanging wire is used to determine the center line and the reference line, and then a laser projection device is used to project clear processing line marks on these lines. Use the probe or laser beam of the laser tracker to perform point-by-point or continuous scanning measurements along the marked processing lines. Record the three-dimensional coordinate data of each measuring point. Compare the measured data with the design model to analyze the position deviation of the processing line. Compared with manual marking, the laser tracker has high measurement accuracy and can significantly reduce measurement errors. And accurate processing lines are the basis of branch pipe processing, ensuring the accuracy of subsequent processing. In addition, through digital measurement, deviations can be discovered and corrected in a timely manner, reducing cumulative errors in subsequent processing steps.

[0039] As another specific implementation method, in step 3, the measured data model is digitally analyzed, and the measured data model is matched with the theoretical data model to determine whether the processing line accuracy of the inlet and outlet surfaces and the flange surface meets the requirements. The data measured by the laser tracker is imported into the three-dimensional modeling software or special measurement and analysis software in the computer. According to the design drawings, a theoretical data model of the branch pipe is established, including the precise position and shape of the inlet and outlet surfaces and the flange surface. The theoretical model should contain all key dimensions and tolerance requirements. The data model obtained by actual measurement is superimposed and compared with the theoretical data model. The analysis software can intuitively display the differences between the two models, including position deviation, shape deviation, etc. According to the design tolerance requirements, it is determined whether the actual measurement data is within the allowable error range. For the part that exceeds the tolerance, it is necessary to mark and analyze it to determine the cause and correction plan.

[0040] As another specific implementation, in step 4, based on the structural process characteristics of the bifurcated pipe and the specific parameters of the processing equipment, a special fixture is designed to meet the processing of the bifurcated pipe on the rotary table. The special fixture can be customized according to the structural process characteristics of the bifurcated pipe to ensure that the bifurcated pipe remains stable during the processing and prevent processing errors caused by vibration or displacement.

[0041] Large bifurcated pipes are large in size, heavy in weight and thin-walled. They have poor processing rigidity, limited layout space on the reloading workbench and are difficult to clamp and fix. Based on the process characteristics of bifurcated pipe processing and the size parameters of the platform, special tooling supports and clamping blocks are designed to ensure safe and reliable clamping and fixing of bifurcated pipes on the turntable.

[0042] The branch pipe support fixture adopts a double-ribbed plate conformal support method. Three support fixtures are designed for one branch pipe. The whole structure is a carbon steel welded structure, which meets the support rigidity and spatial layout requirements.

[0043] As another specific implementation, in step 4, the flange surface must be aligned on the machine tool in accordance with the trend of the model data comparison in step 3. Alignment by table can ensure that the machining datum of the flange surface is consistent with the design model and reduce deviation. Comparison with the model data in step 3 can timely discover and correct potential errors before machining, and can greatly reduce the deviation caused by marking alignment, ensuring machining accuracy.

[0044] As another specific implementation, in step 4, after the alignment meets the requirements, the flange surface and the inlet and outlet surfaces are milled in sequence on the rotary table, and the machining parameters are optimized through trial machining. Milling is performed after the alignment meets the requirements to ensure that the shape and size of the machined surface meet the design requirements. Through trial machining, machining parameters such as cutting speed, feed rate, etc. can be adjusted and optimized to obtain the best machining effect and surface quality.

[0045] As another specific implementation, in step 4, digital measurement is used to detect each processed surface after processing. Through digital measurement, it can be verified whether the actual size and shape after processing meet the design requirements. The measurement results are used for quality control to ensure that the quality of each processed surface meets the standard and reduce the production of unqualified products.

[0046] The present invention is not limited to the above-mentioned specific embodiments, but extends to any new features or any new combination disclosed in this specification, as well as any new method or process steps or any new combination disclosed.

Claims

1. A method for processing a large impact bifurcated pipe by digital measurement and guidance, characterized in that: The following steps are involved: Step 1: Digitally measure and detect the corrected ground sample line; Step 2: Digitally measure and inspect the inlet and outlet surfaces of the bifurcated pipe and the flange surface processing line; Step 3: Using digital analysis technology to determine the detection data model; Step 4: Layout, alignment, processing and inspection of branch pipes based on the rotary table.

2. The method for processing a large impact bifurcated pipe guided by digital measurement as claimed in claim 1, characterized in that: The laser tracker probe is used to locate, detect and analyze the accuracy of manual marking of ground samples, and make corrections.

3. The method for processing a large impact bifurcated pipe guided by digital measurement as claimed in claim 2, characterized in that: Ensure that the overall ground sample marking deviation is within 1mm.

4. The method for processing a large impact bifurcated pipe guided by digital measurement as claimed in claim 1, characterized in that: In step 2, after the processing lines of the inlet and outlet surfaces and the flange surface of the branch pipe are marked by hanging wires and laser projection, a laser tracker is used to detect the marked processing lines.

5. The method for processing a large impact bifurcated pipe guided by digital measurement as claimed in claim 1, characterized in that: In step 3, the measured data model is digitally analyzed, and the measured data model is matched with the theoretical data model to determine whether the processing line accuracy of the inlet and outlet surfaces and the flange surface meets the requirements.

6. The method for processing a large impact bifurcated pipe guided by digital measurement as claimed in claim 1, characterized in that: In step 4, based on the structural process characteristics of the branch pipe and the specific parameters of the processing equipment, a special tooling fixture is designed to meet the requirements of branch pipe processing on the rotary table.

7. The method for processing a large impact bifurcated pipe guided by digital measurement as claimed in claim 1, characterized in that: In step 4, the flange surface must be aligned on the machine tool in accordance with the trend of the model data comparison in step 3.

8. The method for processing a large impact bifurcated pipe guided by digital measurement as claimed in claim 1, characterized in that: In step 4, after the alignment meets the requirements, the flange surface and the inlet and outlet surfaces are milled in sequence on the rotary table, and the processing parameters are optimized through trial processing.

9. The method for processing a large impact bifurcated pipe guided by digital measurement as claimed in claim 1, characterized in that: In step 4, after processing, digital measurement is used to detect each processed surface.

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