他揉捏她两乳不停呻吟a片,亚洲国产成人精品无码区99,无码jk粉嫩小泬在线观看欧美,黑人上司粗大拔不出来电影

The manufacturing of precision stretching and stamping parts should choose standard mold bases as much as possible, and the type and specifications of the standard mold base determine the type and specifications of the upper and lower mold bases.

(1) The mold base materials are generally HT200 and HT250, and Q235 and Q255 structural steel can also be used. For large precision molds, cast steel ZG35 and ZG45 are used for the mold base.

(2) The parallelism of the upper and lower surfaces of the mold base should meet the requirements, and the parallelism tolerance is generally level 4.

(3) The upper and lower surface roughness of the mold base is Ra1.6~0.8 μ m. Under the premise of ensuring parallelism, it is allowed to reduce to Ra3.2~1.6 μ M. Backing plate: The function of the backing plate is to directly bear and diffuse the pressure transmitted by the convex mold, in order to reduce the unit pressure on the mold base and prevent local compression of the mold base. The external dimensions of the backing plate are the same as those of the concave mold, and its fixing method is also fixed with screws and pins.

(4) The center distance between the guide sleeve and guide pillar installation holes of the upper and lower mold seats must be consistent, and the accuracy is generally required to be below ± 0.02mm; The axis of the guide pillar and guide sleeve installation hole of the mold base should be perpendicular to the upper and lower planes of the mold base. When installing sliding guide pillars and guide sleeves, the verticality tolerance is generally level 4.

(5) The mold base selected or designed for precision stretching and stamping parts must match the relevant dimensions of the workbench and slider of the selected press, and undergo necessary verification. For example, the minimum contour size of the lower mold seat should be at least 40-50mm larger on each side than the size of the leakage hole on the press workbench.

(6) If it is necessary to design the mold base by oneself, the diameter of the circular mold base should be 30-70mm larger than the diameter of the concave template, and the length of the rectangular mold base should be 40-70mm larger than the length of the concave template. Its width can be slightly larger or equal to the width of the concave template. The thickness of the precision stretching stamping part mold base can be determined by referring to the standard mold base, which is generally 1.0~1.5 times the thickness of the concave template to ensure sufficient strength and stiffness. For large non-standard mold bases, they must also be designed according to actual needs, casting process requirements, and casting structural design specifications.

Licao Mold is a company engaged in the development of hardware stamping parts, hardware stamping terminals, small automotive stamping parts, contact spring pieces, precision stretching stamping parts, motor component stamping parts, motor chips, new energy hardware parts, automotive connector male and female ends, precision molds, and more.