Inspection Of Gearbox Parts Processed From Large Box Bodies

Inspection of gearbox parts processed from large box bodies

There is a kind of part called a box part. It seems to have nothing special. However, it is the key to determining the life and performance of mechanical equipment. Its processing difficulty and detection difficulty directly affect the manufacturing cost and final quality.

What exactly are cabinet parts?

Workpieces composed of points, workpieces composed of lines, and objects composed of surfaces are collectively called box parts. Common gearboxes fall into this category, as do engine cases, and machine tool processing parts also fall into this category. The raw materials of these objects, which play the basic role of transmission parts in power machinery manufacturing, are mainly cast iron and aluminum alloys. Many manufacturing practitioners come into contact with these items every day.

The surface of such parts is composed of simple free-form surfaces, but it carries core transmission components such as gears and shafts. For example, in automobile manufacturing, the machining accuracy of the engine box directly determines the engine life and noise level. The quality control of box parts is a basic link in mechanical manufacturing.

Challenges faced by large box processing

The inspection procedures for bulky boxes are extremely complicated, and many key dimensions must be measured 100% throughout the entire process. A large-scale engine box will most likely go through dozens of inspection processes from the rough state to the finished product. Workers spend an hour on the machine tool for processing, and the time required for inspection often doubles. This is a considerable test for production efficiency.

In the past, those traditional large-scale box manufacturing equipment are now increasingly difficult to meet precision requirements. This is because many of the markings on the design drawings are coordinate dimensions and complex geometric tolerances, and the old equipment is simply not capable of the job. At present, many key box parts must use special machine tools or CNC machining centers, and must be equipped with precision tools. As a result, manufacturing costs naturally increase.

Three key points that must be accurately measured for large cabinets

When processing large boxes, the three-dimensional position of the workpiece must be accurately locked, which determines the benchmark for all subsequent assembly. For example, if the bed of a machine tool has a deviation of 0.01 mm in its three-dimensional reference, the accuracy of the assembled machine will be greatly reduced. The source of rework at many assembly sites lies in the inaccurate measurement in this first step.

The degree of axis coincidence and verticality are also extremely difficult parts of measurement. Just like the holes in the gear box used to install bearings, if the axis coincidence degree exceeds the specified difference, then there will be problems with the gears meshing with each other, which will increase the noise and heat generated when the equipment is running. In addition, the outline of the cabinet and the coordinates of the parts must also be included in the measurement scope. These are the basic requirements to ensure that the cabinet can be assembled and operated normally.

What are the limitations of traditional measuring equipment?

When traditional measurement equipment encounters complex spatial elements and positional relationships, they are often at a loss. Conventional tools such as calipers and dial indicators can only measure simple length, width and height. However, when faced with the angular relationship between the two oblique holes in the cabinet cavity, traditional methods cannot perform calculations at all. Many old masters rely on experience to work, but experience cannot replace data.

The volume of the workpiece is large and its structure is very complex. This situation also brings a lot of trouble to the measurement. Ordinary equipment cannot reach deep holes and cannot penetrate into narrow grooves. This situation forces the measurement plan to be upgraded. For large cabinet manufacturing companies, if they still cling to old equipment, there will be no way to accept orders for high-end cabinet parts.

Precision measurements require special probes

During the measurement of large boxes , large parts processing measurement technology and the selection of special measuring heads will have a direct impact on the success or failure of the entire process. For example, the overhead crane measurement system can be equipped with a probe base and a star probe, which are specially used to measure deep holes and flat surfaces. A star probe designed to meet reasonable standards can achieve data collection in multiple directions at one time, and the efficiency improvement effect is extremely significant.

In terms of azimuth tolerance and coaxiality measurement of deep blind holes, disc probes are an indispensable tool. Many hydraulic valve bodies and pump bodies have such deep blind hole structures. Without disc probes, these objects would be difficult to detect. It can be said that without the cooperation of these special probes, precision measurement is just empty talk.

How to choose measuring equipment based on batch size

During the measurement of space dimensions and positional relationships required by large cabinet manufacturers, ease of operation is a crucial indicator in selection. If you are in a single batch or small batch production situation, you can consider a manual three-dimensional coordinate measuring machine, which has high flexibility in large-scale parts processing and measurement technology , and the investment cost is also low. Many mold factories use this model of large-scale parts processing and measurement technology for box processing, and manual operation will be more efficient.

When the volume of the workpiece is large and the production batch is also large, it is necessary to consider using CNC measuring equipment. After the program is set, the machine can automatically measure batches of boxes, and the efficiency is greatly improved. In the inspection of gearbox parts for large-scale box processing in automobile engine production lines, hundreds of cylinders come off the production line every day. Only by relying on CNC measurement can we control the quality level.

Which of the most difficult cabinet characteristics you have encountered during actual work is it? Is it the deep hole coaxiality, or is it the spatial angle?