Head is an important component widely used in boilers, chemical containers, oil tanks, nuclear reactors, missiles, and artificial satellites. Its specifications are developing towards large-scale development, and its application fields are constantly expanding. The use of spinning method to process large and medium-sized heads has unparalleled advantages over other processing methods. Head spinning usually uses sheet metal forming, and the wall thickness does not change or changes very little before and after deformation. The diameter changes greatly, or shrinks or expands, making it more prone to instability or local thinning during spinning. There are two methods: unidirectional forward spinning and reciprocating swing multi pass stepwise spinning. The product elements include the contour of the head shape, known position diameter, height, wall thickness, etc.
The main process elements include the trajectory of the spinning wheel, the number of spinning passes, the spacing between passes, the spinning speed, and whether it is hot spinning. The trajectory of the gradually opening linear spinning wheel is most beneficial for spinning forming, and the determination of the distance between the spinning passes is extremely important, directly affecting the success or failure of the spinning process.
At present, there are mainly two methods used in the cold spinning forming of head heads at home and abroad: one-step method, which means that the slab is spun and formed in one go on the spinning machine; Two step method, which involves pressing the slab into a spherical crown shape point by point along the slab surface on a drum press, and then flanging it on a spinning machine. The one-step spinning head has much higher work efficiency than the two-step forming head process, and the product quality is better. At present, the one-step spinning head is in a dominant position and has developed maturely.