The utility model provides a hot
nozzle with an automatic guide valve needle. The hot
nozzle comprises an HD body, a valve needle
assembly arranged in the HD body, a hot
nozzle body, a nozzle core sleeve, a sealing ring and a heat insulation cap, wherein the sealing ring and the heat insulation cap are located at one end of the HD body; a conical sealing surface and a
ceramic lining are arranged at the outlet end of the hot nozzle body; the valve needle
assembly is provided with a stepped shaft structure, a conical sealing head and a split type guide sleeve. A
graphite self-lubricating layer is arranged on the inner wall of the split type guide sleeve, and the thickness is 0.05-0.2 mm; the dynamic compensation
assembly comprises an elastic compensation ring and a floating gap; the radial width of the floating gap is 0.02-0.1 mm, and radial fine adjustment of the guide sleeve is achieved through melt pressure; the elastic compensation ring is a high-temperature
alloy spring, and the adjustable range of the pre-tightening force is 50-200N; the spiral angle of the
spiral flow guide groove in the inner wall of the
ceramic lining is 15-45 degrees, and in practical application, the production and
machining time and the
system maintenance time can be effectively saved, the valve needle is effectively prevented from being deviated, the overall service life of a
system is guaranteed, and the production efficiency of customers is improved.