The bed of the machine is the main reason that affects the accuracy. The manufacture of the bed is especially important. A good machine bed can be unchanged for 15-20 years. However, in the Chinese market, the processing technology of the bed is very different, and often some customers only pay attention to the price, not the quality, resulting in problems with the accuracy of the machine for a period of time. If you are a novice, please pay more attention！ Here i introduce the processing technology of TPLASER machine bed to you as follows.
First, multi-temperature quenching of ductile iron; ductile iron can obtain high strength after isothermal quenching, and has good plasticity and toughness at the same time.
Second, stress relief annealing; due to the uneven wall thickness of the casting, in the process of heating, cooling and phase transformation, effect stress and structural stress will be generated. In addition, large parts are prone to residual stress after machining, and all these internal stresses must be eliminated. The usual heating temperature for stress relief annealing is 500~550℃, the holding time is 2~8h, and then furnace cooling (grey iron) or air cooling (ductile iron)
Third, high-temperature graphitization annealing to eliminate the white mouth of the casting; when the casting is cooled, white mouth often occurs on the surface layer and thin section. The white mouth structure is hard and brittle, with poor processing performance and easy to peel off. Therefore, annealing (or normalizing) must be used to eliminate white mouth tissue. The annealing process is: heating to 550-950℃ for 2~5h, then furnace cooling to 500-550℃ and then air cooling
Fourth, normalizing of ductile iron; the purpose of normalizing ductile iron is to obtain pearlite matrix structure, refine grains, and uniform structure, so as to improve the mechanical properties of castings. Sometimes normalizing is also the preparation of ductile iron surface quenching on the structure, normalizing is divided into high temperature normalizing and low temperature normalizing. The high temperature normalizing temperature is generally not more than 950~980℃, and the low temperature normalizing temperature is generally heated to the common folding temperature range of 820~860℃. After normalizing, four people are generally required to deal with it to eliminate the internal stress generated during normalizing.
Fifth, quenching and tempering of ductile iron; in order to improve the mechanical properties of ductile iron, generally castings are heated to 30~50°C above Afc1 (Afc1 represents the final temperature of A formation during heating), and then quenched into oil after heat preservation to obtain martensitic body tissue. In order to properly reduce the residual stress after quenching, generally, tempering should be carried out after quenching. The low-temperature tempering structure is tempered martensite plus residual bainite and spherical graphite. This structure has good wear resistance and is used for parts that require high wear resistance and high strength.
Sixth, chemical heat treatment; for castings that require surface wear resistance, oxidation resistance, and corrosion resistance, chemical heat treatment processes similar to steel can be used, such as gas soft chlorination, chlorination, boronizing, sulfurizing and other treatments.
The painting process will also affect the life of the machine. If one step is missing, the machine will rust and crack for a long time. If you are a novice and only pay attention to the price and not the machine painting process, I don’t think you can get a good machine. Here i introduce the technical requirements for the painting process (painting process) of TPLASER machine bed are as follows.
1.Before painting the machine bed, check the castings of the bed, use tools to trim the unevenness of the surface, and remove the dirt on the surface.
2. The machined bed casting must be rinsed or brushed with metal cleaner or clean industrial gasoline before painting to ensure that oil and other dirt on the surface are completely removed.
The primer should be applied evenly by brushing, spraying, or dipping. The primer must be fully stirred before use, and diluted to an appropriate year before applying.
3. The putty that fills the depression of the casting should be added with an appropriate amount of curing agent according to the product’s instructions for use, and must be fully stirred before use.
4. If vinyl perchloride is used to fill the depressions of the bed casting, each scraping should not be too thick. The thickness of scraping is generally about 0.5 mm. Each scraping must wait for the material to be scraped to dry before proceeding.
5. After filling the depression of the bed casting with perchloroethylene, it must be dry before grinding. After each grinding, the grinding slurry and dust on the surface need to be completely removed.
6. Use water grinding technology for grinding. In order to prevent the machine tool casting from rusting on the processed surface, it is necessary to use anti-rust water for grinding.
After grinding, if there is metal exposure, it is necessary not to brush the matching primer.
7. After the last putty is polished and cleaned, it is necessary to spray the second primer of vinyl chloride, which can improve the flatness of the paint film and improve the gloss of the paint film.