The invention relates to a new technique for producing a high
alloy steel high-end seamless
pipe by adopting cross rolling elongation technology without perforation, comprising: molten high
alloy steel which is externally refined is made into a hollow shell by centrifugal
casting; the outside surfaces of the front and the rear ends of the hollow shell are respectively processed to be a 'gripping head' and a '
tail end head' with conicity, and
machining and quality inspection are carried out on the inside and the outside surfaces as well as the 'gripping head' and the '
tail end head' of the hollow shell; heating is carried out; a
mandril is inserted into the heated hollow shell, and then the hollow shell is sent into a cross rolling elongating mill for cross rolling, so that the
pipe fittings having the wall thickness, the
diameter and the length being in accordance with the requirements can be produced; the
mandril is removed, and the head and the
tail are
cut off; finally, the qualified finished pipes can be obtained after
sizing, heat treatment for finished product and finishing operation. The technique has short process flow and does not need cross rolling perforation, thus reducing the cost and improving the quality; due to small tapered treatment for the front and the rear ends, 'tail triangle' is avoided when the medium-thick walled pipes are produced, and the performance of secondary gripping is improved, thus improving the quality of the product and the production efficiency.