According to the purpose, it is divided into inspection board, marking board, assembly board, riveting board, welding board and sand pressing board. According to its accuracy grade, it can be divided into 1, 2 and 3 grades, and the highest rock disk can reach 000 grade, of which the second grade is the inspection disk and the third grade is the scribing disk. Two methods: coloring test.
There shall be no less than 25 points within 25mm2 on each side of Class 0 1 Platform.
There shall be no less than 20 points within 25mm2 on each side of the secondary platform.
No less than 12 points within 25mm2 on each side of the tertiary platform.
Smoothness inspection
Smoothness calculation formula: (according to GB/T22095-2008 standard)
000 class:/kloc-0 /× (1+d/1000) μ m.
0 level 0: 2× (1+d/1000) μ m.
Grade 0: 4× (1+d/1000) μ m.
Grade1:8× (1+d/1000) μ m.
Secondary:16× (1+d/1000) μ m.
Grade 3: 40×( 1+d/ 1000) micron (d is diagonal mm) (measuring temperature is 20 2℃). After the cast iron plate is worn, it can be scraped again to restore its accuracy.
It is accurate, intuitive and convenient to detect the flatness of cast iron plate by coloring method. Pushing the table base and workpiece on the scraped cast iron flat plate is smooth, without roughness, which is convenient for measurement and ensures the measurement accuracy.
The cast iron quality and heat treatment quality of cast iron flat plate have great influence on the performance of flat plate; Or the working face is deformed due to residual internal stress; Or because there is no wear and tear, the accuracy cannot be maintained; Or a small value of roughness cannot be obtained due to scraping difficulty. Therefore, we must pay attention to the selection of cast iron materials and eliminate the residual stress of cast iron plates through aging treatment. Standard specification for cast iron flat plates
Cast iron flat plate/cast iron platform is manufactured according to GB/T22095-2008 standard. The products are ribbed plate and box type, with rectangular working face, made of gray iron HT200-300 and HB 170-240. The working face adopts scraping technology, and V-shaped, T-shaped, U-shaped grooves, round holes and long holes can be processed on the working face. Cast iron flat plate is a plane reference instrument used for workpiece detection or marking. The flat plate installation should be adjusted to be horizontal, the load should be distributed on all fulcrums, and vibration should be avoided when using the ambient temperature.
Standard specification of cast iron flat plate/cast iron platform and corresponding level standard: specification accuracy level specification accuracy level 0 1 level 2 3 fine planing level 0 1 level 2 3 fine planing level100 48 26 2500 × 2500 72180 270. 200× 100 5 10 20 3000× 1000 168 248 200×200 5 10 20 3000× 1500 174 1 54 300×200 6 6543 8+02 24 3000×2000 184 275 300×300 6 12 24 3000×2500 186 276 400×300 6 12 24 3000×3000 2 1 0 300 40 0×400 6 12 24 4000× 1000 2 10 300 500×300 6 12 24 4000× 1500 2 10 300 500×500 7 1 4 28 4000× 2000 2 19 3 10 600×400 7 14 28 4000×2500 228 340 600×500 7 14 28 4000×3000 240 360 800×500 8 1 6 3 2 805000× 1500 249 370 800×600 8 16 32 805000×2000 255 375 900×600 8 16 32 805000×2500 264 390 1000×750 9 1 8 36 905000×3000 287 420 1000× 1000 10 20 39 966000× 1500 287 420 1200× 100020 39 966000× 2000 293 430 / kloc-0/500× 100024 48 1206000×2500 300 450 1500× 150025 50 1256000×3000 308 460 2000×65438+ 000026 52 1 298000× 1500 366 500 2000× 1500 56 1408000×2000 370 520 2000×2000 60 152 230 8000×2500 375 530 2500 × 1500 64 / Kloc-0/52 230 8000× 3000 382 570 2500× 2000 68168 2481.There should be no sand holes, air holes, cracks, slag inclusion and shrinkage porosity on the flat working face that seriously affect the appearance and service performance.
2. The casting surface of the flat plate should be clear and smooth, and the paint should be firm.
3. On the flat working face with accuracy level of 0 ~3, the sand holes with diameter less than 15mm are allowed to be plugged with the same material, and their hardness should be less than that of the surrounding materials. There should be no more than 4 sand holes blocked in the working face, and the spacing between sand holes should not be less than 80 mm
4. The flat plate should be made of high-quality fine gray cast iron and other materials, and its working surface hardness should be 170~240HB.
5. Scraping technology is usually used for flat working face. The maximum allowable value of surface roughness Ra is 5μm for the three-level plane working face with scraping processing.
6. The flat plate should be demagnetized and stable.
7. The opposite sides of the flat plate should have threaded holes (or cylindrical holes) for installing the handle or lifting ring device, and the position of the device should be designed to minimize the deformation caused by handling.
8. If a threaded hole (or groove) is set on the plane working face, its position should not be higher than the working face.