How to calculate the pressure vessel head, what kind?

Pressure vessel head sort is more, the commonly used forms including half spherical head, elliptical head, dished head, QiuGuanXing head, taper sealing head, flat cover, flanged convex seal first. From the loading points had an internal pressure and external pressure. 1, the formula of QiuGuanXing head (1) is based on the cylinder formula. For QiuGuanXing head and cylinder connecting parts, caused by the boundary effect of partial membrane stress and bending stress and the effect of modified by coefficient of Q. For different pressure conditions, the Q values from different figure. (2) for large diameter QiuGuanXing head, can consider to head middle spherical surface area and the strengthening of end section in different thickness, strengthen length should not be less than the head. Spherical cap and tee joint must be a section of the cylinder connection structure of full penetration. 2, conical head (1) due to structural discontinuity, joint will produce a large local stress. When the conical shell half-apex Angle & alpha; Less than or equal to 30 degrees, the bending stress is lesser, can be used without ruffled taper sealing head at this moment, when & alpha; > 30 degrees when big end conical shell with folding structure should be adopted, when & alpha; > 45 degrees of conical shell small end also with the transition of folding structure should be adopted. (2) is calculated using equivalent cylinder conical shell thickness calculation formula. To strengthen section also USES a calculation formula for the cylinder size end, modify it and multiplied by the coefficient of stress increment Q; For with ruffled taper sealing head, big end can be calculated equivalent dished head. 3, hemispherical head calculation formula is inferred according to the theory of thin film, according to the container inner diameter or outer diameter as a benchmark for wall thickness calculation. See GB150. 3. 3. In section 4 on the content of the spherical shell. In the cylinder of radius formula based on the equivalent strength and failure criterion, where D = Di + & delta; , people often use formula after finishing. Pitch diameter formula of hemispherical head based on equivalent strength and failure criterion, Same as above with the axial) Are:, where D = Di + & delta; , people often use formula: after finishing. 4, the formula of ellipsoidal head (1) is based on the formula of cylinder, the head and the cylinder shape to the connection parts of the boundary effect coefficient K to reflect. The ratio of long and short axis & alpha; The bigger/b and K value; When the ratio of the long and short axis is greater than 2. 5, head is easy to occur circumferential instability, so will & alpha; / control in 2 b. 6. The ratio of the length of the standard ellipsoidal head shaft for 2, the most common, the K = 1. (2) the head according to the container inner diameter or outer diameter as a benchmark for wall thickness calculation. (3) head thickness calculation in addition to satisfy the intensity, should also meet the requirements of stability. For & alpha; / b less than or equal to 2 oval head, effective thickness shall not be less than zero. 15% Di, & alpha; / b > 2 effective thickness of ellipse head shall not be less than zero. 30%Di。 5, flat cover by coefficient K to reflect the flat cover surrounding supporting situation, the smaller the K value, flat cover around the more close to the clamped, conversely, the more close to the simply supported condition. 6, flanged convex head content packet head thickness calculation and the flange thickness calculation, there are four kinds of forms. The flanged QiuGuanXing head used to floating head heat exchanger. 7, dished head (1) calculation formula is header surface sealing part M correction formula of spherical shell multiplied by the shape coefficient. Ri/r, the greater the head surface of the local stress of the discontinuity of the more prominent, the greater the shape factor M. So the transition section corner inside diameter should be restricted to r> Di = 10% range. (2) the head according to the container inner diameter or outer diameter as a benchmark for wall thickness calculation. (3) head thickness calculation in addition to satisfy the intensity, should also meet the requirements of stability. For M< = 1. 34 dished head, the effective thickness shall not be less than zero. 15% di, m> 1. 34 dished head, the effective thickness shall not be less than zero. 30%Di。 8, eccentric eccentric taper conical shell shell according to conical shell processing. When the conical shell under internal pressure half-apex Angle & alpha; Less than or equal to 30 degrees, the eccentricity of the conical shell thickness calculated on plating shaped head, conical shell half-apex Angle & alpha; According to the eccentric conical shell with simplified the larger value of the two Angle between the selection. Under the action of external pressure, when the half-apex Angle conical shell & alpha; Less than or equal to 60 degrees, the thickness of conical shell stability checking according to conical shell under external pressure, checking should be according to the half-apex Angle separately.