Issues regarding the pressing die for spherical tank shell plates
Thread Content
The pressure die for spherical tanks is divided into an upper die and a lower die; what are the requirements for selecting the radius of curvature?
The radius of curvature depends mainly on the material; it’s fine if it’s as small as possible, since a smaller value allows for a larger diameter. The opposite is not true. . For our company, for diameters of 20 meters or less, the radius is 1000 units smaller than the actual value; for diameters over 20 meters, the radius is 1500 units smaller. The area of the upper die is 80% of that of the lower die, which means the lower die is larger than the upper die ； That’s all I can say, haha. What if the company’s management finds out? It would be terrible. . .
The radius of curvature of the upper and lower dies used for pressing spherical shell plates can be calculated using formulas (1) and (2): Rt1 = R(1 – E) (1) Where Rt1 represents the radius of curvature of the upper die sphere, in mm; R is the nominal radius of the spherical shell plate; E is the amount of springback (%), with values ranging from 15% to 30% for low-alloy steel plates of different thicknesses. Rt2=Rt1+S+Z (2) Where Rt2----is the radius of curvature of the lower bulb, in mm; S-----is the thickness of the spherical shell plate, in mm ； Z-----Mold fitting clearance (usually 0.1~0.25).
What size ball mold is generally used for 500-liter spheres? ?
It depends on your press and other conditions
Many times, there’s no need to think about so much! The design sets requirements, and production uses qualified components to carry out work. This is a concern for end cap manufacturers.