Green forging process method of transition segment

Abstract

The invention belongs to the technical field of forging, and particularly relates to a forging process method of a transition segment. According to the forging process method of the transition segment, a forging blank is manufactured by adopting the process scheme of hammer cogging by free forging and profiling rolling forming. The forging process method specifically comprises the steps of calculation of the size of the rolled blank, determination of process parameters such as the raw material ingot weight, re-inspection of raw materials, furnace charging and heating, rolling, hot chopping ofa water riser, heading, punching, reaming profiling rolling, post-forging heat treatment, rough machining, non-destructive testing, performance heat treatment, sampling testing and finish turning. According to a manufacturing method provided by the invention, the amount of the raw materials used can be reduced by more than 10%; and profiling rolling can further improve the blank quality, the machining efficiency is improved, the manufacturing cycle is shortened, and the overall manufacturing cost is reduced.

Description

technical field [0001] The invention belongs to the technical field of forging, and in particular relates to a forging process method of a transition section. Background technique [0002] The transition section is an important connecting forging between the cylindrical forging and the bottom spherical head in the pressure vessel. It must serve for a long time under the condition of alternating cold and hot fatigue loads, and must withstand high temperature alternating loads, high temperature creep, low cycle thermal fatigue and rapid cooling. Rapid temperature difference thermal stress. In addition, because the size of the cylindrical forging is different from that of the bottom spherical head, the shape of the transition section belongs to a large forging with special-shaped cross-section (as shown in the attached figure 1 shown), so its manufacture is more difficult. [0003] In order to ensure the safety and reliability of the entire pressure vessel, the transition sec...

AI Technical Summary

Problems solved by technology

In the production process, due to the influence of equipment and thermoforming process, the free forging method has four shortcomings: First, the forming size is affected by the equipment and cannot meet the needs of large sizes, such as a 5 million t / a delayed coking device. The transitional section with a diameter greater than 9 meters adopts the production method of segmented forging and then welding; second, there are many forging fires, large processing allowances, and long production cycles are not conducive to environmental protection and lower overall manufacturing costs; third, the forging time per fire Longer, the deformation temperature and deformation amount of each pass are inconsistent, and the uniformity of the structure is poor; Fourth, the free forging shape is generally a rectangular cross section, and the metal flow line is cut off during the subsequent machining process, which affects the later service life of the forging

The forgings in the super-large transition section basically adopt the form of forging welding, and the structure of the weld area is very different from that of the forging body, and there will be great safety hazards in the actual use process

Images