Inspection of construction machinery and components
Construction machinery is an important part of the equipment industry. To sum up, all the mechanical equipment necessary for the comprehensive mechanized construction engineering required by the earthwork construction engineering, pavement construction and
Maintenance, mobile crane loading and unloading operation and various construction engineering are called engineering machinery.
Based on its purpose, the construction machinery has been in the construction environment for a long time and bears various external forces. Therefore, during the manufacturing process, the requirements for the processing quality of its structural parts are very strict. The inspection tolerance requirements are usually 0.1mm-0.2mm. The key parts of the core key parts, such as the coaxiality tolerance at the hinge point, the flatness and parallelism of the bearing roller shaft end face, and the position tolerance of the connecting part hole, etc, The requirement is 0.05 mm or higher.
The measurement accuracy of construction machinery components is high, but these components often have the characteristics of large volume and mass, which makes the traditional CMM and articulated arm have no advantages in measuring range, efficiency and convenience when detecting these components. The application of
Laser Tracker has successfully met the needs of large size and high precision measurement in this field.
Figure 1: API brand Radian series laser tracker (left: Pro model; middle: Plus model; right: Core model)
API laser tracker solution
In view of the high accuracy measurement requirements of construction machinery structural parts, the use of API brand Radian series laser tracker, together with the corresponding function expansion accessories, can achieve perfect detection. Radian laser tracker is an efficient solution for large size and precision measurement, with micron( μ m) The measurement accuracy of level, with the measurement range of 160m, can provide accurate measurement guarantee for all links in construction machinery manufacturing.
During the measurement, the operator holds the laser tracker target ball (SMR) with built-in prism to touch the part to be measured (as shown in Figure 3), the laser tracker host will shoot a laser to lock and track the center of the SMR, and when the SMR touches the part to be measured, the 3D coordinates of the point to be measured will be accurately collected at the acquisition rate of 1000Hz, and transmitted to the
Measurement Software for recording and saving. After several such points are collected on the workpiece, the corresponding lines, surfaces and bodies can be formed in the software according to the position of each point, and the corresponding shape and position tolerance data can be calculated, and can also be compared with the digital analog to achieve the purpose of measurement and detection.
Figure 2: Radian laser tracker function expansion accessory - vProbe hidden point probe
Figure 3: Measurement diagram of Radian laser tracker (the main picture shows the use of SMR target ball; the small picture shows the use of function expansion accessory vProbe hidden point probe)
Analysis of real measurement cases in the field of construction machinery
Figure 4: Rotor to be milled (main figure) and end face (upper right: end face A; lower right: end face B)
. Rapid detection of the parallelism of the end face of the rotor milled by a milling machine
1. Measurement background&measurement requirements
Milling machine is one of the main types of asphalt pavement maintenance and construction machinery, mainly used for the excavation and renovation of asphalt concrete pavement. In the structure of the milling machine, the "milling rotor" is its core component, which is a roller-shaped part with multiple cutters installed on the surface. It rotates at high speed during excavation and is used for crushing asphalt or concrete surfaces.
As it is the most direct part for crushing operation, the milling rotor is also subject to multi-directional external forces while rotating at high speed. Therefore, the working stability of the component itself becomes the most important. Therefore, in the manufacturing process, the inspection requirements for the component are also extremely strict.
In this case, the API brand Radian Plus Laser Tracker will be used to quickly detect the parallelism of a certain type of milling machine milling rotor end face (as shown in Figure 4).
Figure 5: Measurement site (small picture) and analysis report (main picture) of milling machine milling rotor end face
. Radian laser tracker field measurement
At the measurement site, the operator first sets up the Radian laser tracker at a suitable position around the milling rotor, and then on the two end faces to be measured (end face A and end face B), uses the target ball to coordinate with the tracker to measure the data, and then uses the preset common point to substitute the data of the two end faces into the same coordinate system, so that the geometric parameters of the two end faces and their relationship can be easily analyzed in the measurement software.
. Rapid detection of hole position of roller shaft connecting parts
1. Measurement background&measurement requirements
The connecting parts of the roller shaft (or other stressed positions) not only serve as the connecting hub, but also bear the external forces from many directions and types at the same time. Therefore, the requirements for the position error of each part of the connecting parts are extremely strict. The detection of the errors of these parts is also one of the links with high requirements for geometric measurement in the construction machinery manufacturing process.
Figure 6: Schematic diagram of parts to be tested and holes to be tested
In this case, the item to be measured is the position parameter of each hole (as shown in Figure 6) on the connecting part of a certain type of construction machinery, and an analysis report on the relationship between each hole is issued based on the measured data.
Figure 7: Measurement site - use SMR target ball and cylindrical pin ball seat to fit hole wall for spot measurement
2. Radian laser tracker field measurement
During the field measurement, the operator puts the tracker in place and uses the high-precision tracker target ball (SMR) with the cylindrical pin ball socket (as shown in Figure 7) to collect data from each hole. During the collection, the SMR target ball is adsorbed on the cylindrical pin ball socket, and the cylindrical pin part of the ball socket is used to fit the inner wall of each hole to collect the circumference data. By taking points several times, the center position of each hole can be calculated in the software through the circumference, so that the position degree and the relationship of each hole can be analyzed (see Figure 8).
Figure 8: Component measurement site (small picture) and data report (main picture)
conclusion
The two cases in this paper fully show that the API Radian laser tracker, with its characteristics of large size, high accuracy, portability, and flexible installation, can fully meet the requirements of high-quality and efficient measurement of construction machinery components, and is widely applicable to large-scale and high-precision geometric measurement in many industries and fields, including construction machinery manufacturing.
