An online section of "Today I will introduce the name of Northeast China, which has caused great resonance. We are called Kuayan." To scrape is a verb. To scrape is to scrape off the high points with a scraper. To grind is to grind out the high points of the surface to be scraped with a flat plate or other grinding tools. Let's talk about shovel flowers, my understanding is for decoration, such as shovel swallows and shovel patterns.

The manufacture of modern machine tools is also inseparable from high-end machine tools. Scraping is a powerful guarantee for the perfect expression of machine tool accuracy. Modern machine tool scraping mainly involves the combined grinding of the sliding parts of the machine tool's guide rail, the surface precision of the worktable, the rotating surface of the worktable, and the sliding joint surface of the headstock. Due to the advancement of science and technology, the scraping and grinding of machine tool rails has been replaced by high-precision rail grinding, and the process of machine tool rails has also changed. Machine tool cast iron has H200 replaced by H300, and intermediate frequency quenching has been added to the rail surface to improve the wear resistance of the machine Degree, improve the service life of the machine tool. The sliding parts of the machine tool have also changed from cast iron friction to plastic or zinc-based alloy plates, but even the best materials must be manually scraped. 》

 

 

 

 

The so-called "scraping" refers to the operation of scraping and grinding the surface of an object using tools such as shovel and scraper. The places where scraping is performed are friction surfaces (moving parts such as table tops and cylinders), object-to-object contact surfaces, table tops, platforms, etc. By scraping, the amount of grinding at one time is about 1 to 3 μm. As long as the amount of scraping is grasped, free shapes can be produced accurately. Skilled workers can obtain flatness, straightness, and straightness that are difficult to achieve by machining.

The process of "scraping"

When processing the correct working surface by scraping, there must first be a benchmark. That is, the flat plate made by "three-sided running-in" explained below is called "running-in jig". There will be slight undulations, high parts and low parts on the surface after scraping. Paint red on the processed surface, and then run in with the running-in jig. In this way, the red of the high part will be scraped off. Scrape the part where the red color was removed again, and repeat this process to create an ultra-precision plane.

 

 

 

 

 

The traditional manual "scraping and scraping" technology is adopted to ensure that each contact surface of the machine tool's castings is "shoveled and scraped", and 25 points per square inch are guaranteed, which greatly guarantees the flatness and run-in of the contact surface. Benefits of "Scraping and Scraping" technology:

① "Scraping and scraping" technology greatly improves the accuracy of the machine tool.

②Improve the running-in accuracy between the castings.

③Between the bed and the cylinder, between the spindle head and the spindle, between the ball screw attachment and the attachment surface, etc., the important parts of the contact between the object and the object should be scraped and processed. Simply put, it means "eliminate tension"

④The accuracy (including straightness and right angle, etc.) of the moving friction surface of the table, cylinder, spindle head, etc. is an important element of machine tool accuracy. The friction surface is important because the object will move on the friction surface. It is not only required to be able to move in a straight line, but also to pay attention to changes in the center of gravity during the movement. The precision of the friction surface is greatly enhanced through the "shovel and scrape" technology.

⑤When the surface processed by the "shoveling and scraping" technology is rubbed, the small undulations on the friction surface will deposit oil and form an oil film, which will be very helpful to the lubrication of the friction surface.

 

 

 

 

 

 

 

1. Purpose 

     Standardize the inspection methods and procedures of the inspectors, control the defective joints of the shoveling position, and ensure that the surface quality after shoveling conforms to

Stipulated requirements to ensure product quality.

2. area 

     This specification applies to the inspection of the company's shoveling position and the surface quality after shoveling.

3. Refer to standard JB/T 9876 4. Precautions before shoveling

  ① All parts and components shall be free of any visible defects such as pinholes, shrinkage holes, shrinkage porosity and cracks before shoveling;

  ② The working environment should be in a clean place, without the influence of serious earthquake source.

5. Inspection

5.1 Use tools

Display/colorant (red lead, blue lead), painting, spreader, flashlight, visual, camera The recommended ratio of red lead paint is as follows: red lead: machine oil: kerosene = 100: 7: 3

5.2 Inspection method-research point inspection method

In the assembly process, the inspection of the contact quality of the two joint surfaces should generally be conducted directly by the joint research and inspection of the two joint surfaces. If it is difficult to directly research and inspect due to structural reasons, it is allowed to use inspection tools to inspect the two joint surfaces separately. When using the inspection tool for joint research, the length of the inspection tool should generally not be less than the mating length of the replaced part.

When the two bonding surfaces are directly researched and inspected, if both bonding surfaces are both machined or scratched, the coating can be applied to the reference surface or the matching surface; if one of the two bonding surfaces is the scratched surface, The paint should be applied on the scratched surface.

①Spread the display agent (red lead) evenly on the position after shoveling (such as the mating surface of the column of the MC-500 base), and evenly coat the coloring/display agent (blue lead) on the reference plane (such as the column Fitting surface of the base). The coating must be thin and uniform (the thickness of the coating should be ≤0.005mm);

②Use the reference plane (such as the base fitting surface of the column) to research the scooped surface (such as the base fitting surface of the column).

  Generally 3 to 5 times of research. The surface force must be uniform during the research; the stroke during the joint research of the guide rail pair: When the linear motion guide pair is researched together, the matching surface should be researched together within the working range of the reference plane, and the stroke distance should not be greater than 1/2 of the matching length .

③After the reference surface (such as the base fitting surface of the column) and the shovel surface (such as the base fitting surface of the column) are separated, visually (with the help of a flashlight if necessary) check the shovel surface, whether the joint meets the requirements ( Pay attention to the distinction between true points and false points).

 

④Inspection of the number of research points/joint points: cover a jig (thin iron sheet) with a square hole of 25.4mm X 25.4mm on the plane to be inspected, and count the number of joints in the hole (any position in the entire plane) Sampling inspections should reach the specified points)

5.3 Acceptance criteria

5.3.1 When the paint is applied to the matching surface, the bright spots, black spots and dark red spots appearing on the matching surface after joint research are used as the basis for evaluating contact. When the paint is applied to the reference surface or the inspection tool, the bright spots, black spots and dark red spots on the matching surface after the joint research are used as the basis for evaluating the contact.

5.3.2 After the shoveling surface has been shoveled, the shoveling surface should be smooth and free of wear marks or scratches. The joints are clear, obvious, and evenly distributed. The wear is relatively small, the contact rigidity is better, and the shovel point density is about 12-18 joints/square inch. Real junction: The junction shown after the research is a black dot on a red background, no flash, and a clearer vision.

5.4 Matters needing attention

① Selection of display/coloring agent, cleaning of the shoveling position before coloring;

    ②When using the display agent, you must pay attention to cleaning, and prevent sand, iron filings or other dirt from being mixed in to avoid scratching the surface of the shovel when you grind the points;

③Before the research point, the reference plane and the shovel surface must be clean, and the applied coloring/display agent must be uniform;

④In the process of joint research, it is necessary to handle with care, and proper use of manpower should be used to make the surface of the research point uniform; prevent deformation of external force when moving, and the amount of movement must be appropriate;

⑤When researching points, the movement stroke of the reference plane should be appropriate (when moving the research tool, prevent the suspended part from exceeding 1/4 of the full length of the reference plane); ⑥The area of ​​the reference plane should be no less than 3/4 of the workpiece grinding surface;

⑦Shovel the flower surface, and there is no wear marks, tear marks, scratches, iron filings, impurities, dirt, etc. on the surface after grinding; ⑧Avoid the influence of sunlight and surrounding heat sources on the research point.

Remarks: Shoveling and researching are generally carried out alternately