Research On Production Process And Design Of Main Engine Equipment On Heavy And Medium Section Ductile Iron Casting

The production line of horizontal continuous casting with single machine which has double castabilityies and double-driving was researched to cast heavy and medium section cast iron in this paper. The type of this machine is DZSL—300. This machine could resolve the problem that the present horizontal continuous casting equipment could not satisfyied the extremely stable producaton of the heavy section ductile iron bars. It can also resolve a series of ductile iron bars quality problem that caused by the low cooling rate of the heavy section ductile iron bars. These problems were caused by the limitation of the billet withdrawing technology for the unreasonable design of main engine. Heavy section ductile iron bars, were produced stability by selected the reasonable production process using this production line. The microstructure and properties is well through the experimental verification Besides, The influence of micro-alloying of element Sb and pretreatment process on the microstructure and properties was also researched. The main contents are as follows:The mechanical part, electric control system and the the corresponding hydro-electric control system of the dragger of production line of horizontal continuous casting were designed and manufactured. The main shaft and the drawing roller was designed to the one system structure through the mechanical part of the dragger. The axially groove of lower roller surface was machined equably to increase the friction force. The radial groove face with V shape was machined to avoid the spin phenomenon of theductile iron bars occurred. The special water cycle cooling system was setted to satisfyied working environment and conditions with the long product time and continuous high working temperature during the production of the heavy section ductile iron bars. The control system adopt the main and assistant two sets of staples speed regulation system with high accuracy which has innovative characteristic. During the actual using process, it runs placidly and reliably, the control system has high control accuracy, and it also has good serviceability.The reasonable chemical constituents was chosen according to the characteristics of the heavy and medium section ductile iron bars. The advanced, simple and cheap secondary cooling equipment was adopted at the exit of the profile crystallizer Yt-based heavy rare earth magnesium alloy was used as nodulizer, pouring process was adopted to realized the spheroidization. 75 silicon iron was used as inoculant, secondary inoculation method was used, besides, the proper processing parameter was adopted. The heavy section ductile iron bars with excellent microstructure and properties was obtained by the finally experiment.Kinds of heavy section ductile iron bars produced by the horizontal continuous caster were analyzed through the measured data from the appearance quality, microstructure, and properties, the results indicates that heavy section ductile iron bars has excellent properties, Filling in the domestic blanks ,realized the industrialization of the production. The reasons for the excellent properties were analyzed theoretical from the microstructures.Meanwhile, the influence of the pretreatment process and the addition of the trace alloying elements Sb on the microstructure and properties of the heavy section ductile iron bars were researched by productive experiment. The experimental datas indicates that these two kinds of processes could improve the quality of the ductile iron bars in varying degrees. Micro-alloying could increase the content of the pearlite in matrix.