NEW TECHNOLOGY FOR FEEDING BLACKSMITH INGOTS

Abstract

Purpose. To make a comparative calculation of the geometric parameters of overfills for blacksmith ingots according to traditional and experimental technology using modern heat-insulating products – domestically produced cross-bars, one of the components of which is paper.
 Research methods. Proven engineering methods of calculations of overflows for ingots and castings, based on the experience of domestic and foreign foundries, as well as our own practical experience and scientific research.
 Results. The calculations of the size of overburden (head) for nine ingots (weigh from 1 to 15 tons) conventionally divided into three groups by design and execution. All parts – the pourer, the through tray and the overflow attachment are made separately, for the ingots of the first group. Assembled, these elements form a casting mold, which is installed on a pallet (2- or 4- place) and filled with a siphon through the central one. According to the current technology, the castings of the first group were lined with the usual molding mixture with liquid glass, sealing in the space between the model and the case of the casting attachment, followed by thermal drying. For drains of the second and third groups, the spouts are also through, pouring – with a siphon on a pallet. The overflow attachment is also removable, it was lined with fireclay bricks and then dried. Structurally, all ingots represented a pressed cone with an upward expansion and a wavy side surface, the bottom part of the ingot represented a pressed cone with an upward expansion and a smooth side surface, the overflow – a pressed cone with an upward narrowing and a smooth side surface.
 Scientific novelty. The vast majority of cases, using cross-bars, the estimated efficiency coefficient of the overfill is 0.28, which made it possible to significantly reduce the size of the overfill and obtain a significant saving of liquid metal for each casting or ingot, was established. For conventional technologies traditionally used in the practice of making blacksmith ingots, the coefficient of effectiveness is 0.19 (for a combined form: the sand part of the form for the overfill and the metal part for the working part of the ingot) and 0.11...0.14 – for a completely sand form.
 Practical value. A method of calculating overfills under the lining with their modern heat-insulating products – cross-bars – has been developed. Due to the favorable thermophysical properties of the material of the cross-bars, it is possible to reduce the size of overflows and, thereafter, reduce the consumption of liquid metal. The use of cross-bars instead of the above-mentioned technologies also significantly improves sanitary and hygienic conditions and a productivity at the site of the preparation of overfills for pouring. New power supply technologies and constructions of overflow extensions for the cross-bars, which have been in operation for about 6 years (the first group) and 3 years (the second and third groups), have been developed.