Full-size quick blade detection method and equipment

[0021] As attached figure 1 As shown, the method for rapid detection of full-size blades in this embodiment is based on a three-dimensional optical measurement system and surface structured light projection profilometry to detect blades, and an optical three-dimensional scanning measuring head projects a sinusoidal fringe profile structure on the surface of the tested blade Light, use heterodyne multi-frequency phase shift method to solve and unfold the phase, take phase as the constraint condition of image matching, use the limit constraint relationship in binocular stereo vision to obtain the blade profile 3D point cloud data, and realize the blade profile optical measurement Because the shape of the blade is complex, it is difficult to obtain complete data in a single measurement, so multiple measurements are required to obtain the measurement results of the entire blade by splicing. The detection method includes the following steps:

[0022] A. Establish a blade holder with adjustable relative position to the optical three-dimensional scanning measuring head of the measurement system, and set mark points on the blade holder for subsequent data splicing. The number and position of mark points are selected according to the actual situation, based on the principle of photogrammetry and The beam adjustment optimization method obtains the marker point coordinates;

[0023] B. Input the mark point coordinates obtained in step A into the 3D measurement software, and establish the original model of the front and back sides of the blade support and the basic coordinate system on the computer;

[0024] C. Install the tested blade on the blade holder, and the blade clamping method is characterized by pneumatic fast clamping;

[0025] D. The optical three-dimensional scanning measuring head measures the blade holder and the blade together. The computer aligns the measured mark point coordinates with the mark point coordinates described in step B by identifying the mark point characteristics of the blade holder, and loads the measurement data into the step B. In the original model described, complete a single measurement;

[0026] E. The computer combines the measurement results of step D in the basic coordinate system established in step B, and the content of the combination includes the single measurement data of the measured blade that has been stored by the computer and obtained by executing step D multiple times;

[0027] F. The computer judges whether the combined result of step E is complete blade profile data;

[0028] G. If it is complete, optimize the measurement results and finish the measurement. Import the data into the self-developed special measurement software for steam turbine blades, make errors on the key dimensions of the blades, analyze the measurement results with analysis and processing software, and print the test report; if incomplete , The three-dimensional position of the blade holder is adjusted by rotation, swing and translation. After the blade holder and the blade rotate, swing and translate to a suitable position, return to step D and perform the next measurement.

[0029] As attached figure 2 , 3 As shown, the device for rapid full-size detection of blades in this embodiment detects blades according to the above-mentioned method for full-size rapid detection of blades, including a stepping motor 4, a high-precision screw guide 2 and The measurement component is composed of the optical three-dimensional scanning measuring head 3. The optical three-dimensional scanning measuring head 3 is preferably a blue optical three-dimensional scanning measuring head. The motor 4 drives the optical three-dimensional scanning measuring head 3 through the control system to move in the vertical direction on the high-precision screw guide 2 , Used to adjust the measuring height of the optical three-dimensional scanning measuring head 3, the high-precision screw guide rail 2 and the base platform 1 are fixedly connected, and also include a blade support, a two-axis turntable 8 and a slide 9. The blade support includes: a frame-type marking point support 5 and a blade clamp 7. The frame-type marking point support 5 is a frame-shaped structure with one side open, including an upper frame 5-1 and a side frame 5-2, and signs are pasted around the frame point. The blade clamp 7 is a pneumatic clamping device. The blade clamp 7 is located between the two side frames 5-2 of the frame marking point bracket 5. In order to measure blades of different sizes, the side frame 5-2 of the frame marking point bracket 5 can be used. In the disassembly design, the side frame 5-2 is composed of a set of support columns, and the adjacent support columns are connected by threads. With this design, the frame height of the frame marker point bracket 5 can be adjusted at any time according to the size of the blade. In order to facilitate installation, the upper frame 5-1 and the side frame 5-2 of the frame type marker point bracket 5 are connected by threads. The frame type marker point bracket 5 and the blade clamp 7 are respectively fixedly connected to the upper surface of the two-axis turntable 8. For the convenience of connection, an installation platform can be provided under the side frame 5-2 of the frame type blade fixing bracket 5. The two-axis turntable 8 and the slideway 9 form a connection structure in which the two-axis turntable 8 can rotate in both directions and slide along the slideway 9. The two-axis turntable 8 is a professional two-axis turntable that drives the measured blade 6 around the vertical direction While rotating and swinging in the horizontal direction, the two-axis turntable 8 is installed on the slide 9 to adjust the distance between the measured blade 6 and the optical three-dimensional scanning measuring head 3 of the measuring assembly. The slide 9 and the base platform 1 are fixedly connected, and the base platform 1 connects the device for rapid detection of full-size blades in this embodiment into a whole. The invention realizes batching and automation of the blade detection process, and greatly improves the efficiency of blade full-size measurement.