Manufacture method of ultra-large-diameter pipeline extruded nozzles

Abstract

The invention relates to a manufacture method of ultra-large-diameter pipeline extruded nozzles. The method comprises the following steps of: straightening and finishing a stainless steel tube blank, so as to ensure that the straightness and the size of the stainless steel tube blank is uniform, rapidly heating the treated stainless steel tube blank through an induction coil, so as to ensure that the temperature of the stainless steel tube blank reaches 1,150 to 1,200 DEG C, preheating a die, keeping the preheating temperature at 100 to 200 DEG C, conveying the heated stainless steel tube blank into the die, ensuring that the temperature of the stainless steel tube blank is more than 1,100 DEG C, inserting a core rod into the stainless steel tube blank, applying force to the guide section side of the core rod from the extrusion side of the core rod, and performing one-way extrusion, so as to ensure that steel is filled in die holes of the die and to extrude a nozzle shape. By adopting the method, not only can nozzles be produced in ultra-large-diameter stainless steel pipelines, but also the nozzles have good physical properties, material is also saved, and the operability is high.

Description

technical field [0001] The invention relates to a method for manufacturing an extruded nozzle, in particular to a method for manufacturing an extruded nozzle for an ultra-large diameter stainless steel pipe. Background technique [0002] In the domestic independent CAP1000 nuclear power technology, it is necessary to adopt super large-diameter stainless steel seamless pipes with a diameter close to 1000mm, and there must be corresponding conduction nozzles on the pipes, and the pipes and nozzles must not be welded links, but must be an integral structure. The service life of the pipeline design must meet at least 60 years without replacement. To meet these requirements at the same time puts forward high requirements on the performance of the pipeline, especially if the corresponding non-welded lead-through nozzle is installed on such a large-scale pipeline. To meet the corresponding physical properties. If it is only to obtain integral large-scale pipes with nozzles, the ca...

AI Technical Summary

Problems solved by technology

The disadvantages of this method are as follows: 1. The wall thickness of the hollow tube is very thick, it is difficult to directly forge through the center part, and the grain size is relatively thick. After processing into finished products, the grain size detection is often unqualified.

2. The amount of machining is huge, the metal utilization rate is less than 30%, and the processing cost is extremely high

The scrap rate is high, and any error in any link will lead to the overall scrap, the loss is basically tens of millions, and the industrialization effect is poor

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