Head purposes: ● head the petrochemical, pharmaceutical and many other industries atomic energy to the food in the pressure vessel equipment indispensable components. ● pressure vessel head is on the cover, is one of the main pressure vessel pressure parts. ● head pressure is directly related to the quality of long-term safe and reliable operation of the container. The importance of head shape: National GB150 head shape of the relationship between the thickness and the necessary cross-sectional shape of the head head on the center of curvature of the design of the required thickness of the cylinder head when the thickness is 20mm head Design Thickness hemispherical (HH) R = D * 0.5 thickness of the plate cylinder 1/2 10mm 2:1 FREQUENCY circle (EH) R = D * 0.9 (approximate value) of the same thickness and the cylinder plate 20mm 10% dish head (DHB) R = D shell plate thickness * 1.54 31mm flat cap (flat) R = infinite cylinder plate eight times the thickness of 160mm head shape requirements: JB/T4746 closure Head standards: ● head must be full sample checks shape. ● Shape tolerance: convex no more than 1.25% Di, recessed no more than 0.625% Di. ● Transition patterns within a radius of not less than the specified value. ● spherical body: head size affects the curvature of the transition section thickness ●: lower sphere and cylinder connection peak stress ● Straight Edge: Avoid transition peak stress and the cylinder group of welding stress superimposed on the characteristics of a thermal processing without the heating , material deterioration does not occur, especially for stainless steel machining head. Due to heat, material degradation will occur, resulting in decreased corrosion resistance stainless steel head is not suitable for processing stainless steel head. (2) without heating, no dimensional change due to cooling shrinkage, regular shape, size, accuracy and consistency thermoforming, resulting in the mold to heat expansion and contraction of the cooling head, the size difference is difficult to control and consistency. 3 without the heat, head to maintain the original material after forming the surface smooth surface, beautiful appearance. Due to heating, head after forming surface oxide serious and difficult to remove. Longwan Hongyu Metal Head Factory Add: Wenzhou City view golden sand town seven A Tel :0577 577 -86925750 -86925157 Fax Mobile: 13057722577 15355996788 Contact: Sun Shaodi URL: www.hyft.cn