SU988517A1

SU988517A1 - Method of dismounting

Info

Publication number: SU988517A1
Application number: SU813302283A
Authority: SU
Inventors: Иван Павлович Ушаков
Original assignee: Производственное Объединение "Ново-Краматорский Машиностроительный Завод"
Priority date: 1981-06-17
Filing date: 1981-06-17
Publication date: 1983-01-15

Description

Изобретение относится к машиностроению, в частности к технологии сборочно-разборочных работ,! и может быть применено для разборки соединений с гарантированным натягом.The invention relates to mechanical engineering, in particular to the technology of assembly and disassembly ,! and can be used to disassemble joints with guaranteed interference fit.

' Известен способ разборки соединений с гарантированным натягом, заключающийся в охлаждении охватываемой детали охлаждающей средой при ограждении ее свободной поверхности изолирующим экраном [ 1 ].'There is a known method of disassembling compounds with guaranteed interference fit, which consists in cooling the covered part with a cooling medium while enclosing its free surface with an insulating screen [1].

Недостатком известного способа является необходимость нагрева сопряженных деталей что может привести к нежелательным температурным деформациям и повреждениям со-, пряженных деталей.A disadvantage of the known method is the need to heat mating parts, which can lead to undesirable temperature deformations and damage to mated parts.

Цель изобретения — повышение качества разборки соединений с гарантированным натягом.The purpose of the invention is to improve the quality of disassembly of joints with guaranteed interference fit.

Поставленная цель достигается тем, что согласно способу разборки, заключающемуся в охлаждении охватываемой детали охлаждающей средой при ограждении ее свободной поверхности изолирующим экраном, на свободную поверхность, охватываемой детали предвари2 тельно наносят покрытие в виде гигроскопи- . ческого материала, а изолирующий экран устанавливают на это покрытие, после чего на по-. крытие подают охлаждающую среду.This goal is achieved by the fact that according to the method of disassembling, which consists in cooling the covered part with a cooling medium while enclosing its free surface with an insulating screen, the free surface of the covered part is preliminarily coated with a hygroscopic coating. material, and an insulating screen is installed on this coating, and then on. the roof serves a cooling medium.

На фиг. 1 изображено соединение деталей перед разборкой, общий вид; на фиг. 2 — разрез А—А на фиг. 1.In FIG. 1 shows the connection of parts before disassembly, a general view; in FIG. 2 — section A — A in FIG. 1.

Способ осуществляется следующим образом.The method is as follows.

Охватываемую деталь 1 покрывают гигроскопическим материалом 2, который накладывают на поверхность детали 1, прилегающую к сопряженным поверхностям соединения. После этото гигроскопический материал 2 закрывают от внешней среды непроницаемым экраном 3 с теплоизолирующей рубашкой 4. В экране 3 имеется заливное отверстие 5, в которое заливается хладагент - жидкий азот. При достижении температуры в месте контакта деталей 0°С или ниже, что характеризуется появлением инея на охватываемой де тали, со стороны, противоположной охлаждаемой, происходит ее температурная деформация, что способствует снятию натяга в месте сопряжения деталей.The male part 1 is coated with absorbent material 2, which is applied to the surface of the component 1 adjacent to the mating surfaces of the joint. After this, hygroscopic material 2 is closed from the external environment by an impermeable screen 3 with a heat-insulating jacket 4. In screen 3 there is a filler hole 5 into which the refrigerant is liquid nitrogen. When the temperature at the place of contact of parts reaches 0 ° С or lower, which is characterized by the appearance of frost on the covered part, from the side opposite to the cooled one, its temperature deformation occurs, which helps to relieve tension at the place of mating of parts.

Пример. Способ применен при демонтаже зубчатой втулки с вала подъемной машины 2Ц-5х2,5. Втулка выполнена с внутренним диаметром 690 мм и установлена на валуExample. The method is applied when dismantling the gear sleeve from the shaft of a lifting machine 2C-5x2.5. The sleeve is made with an inner diameter of 690 mm and mounted on the shaft

А —— . Шейка вала в зоне приПр2₃ по посадке 690 летающей к зубчатой муфте,на длине 200 мм покрыта гигроскопическим материалом — асбестовым полотном в три слоя. Асбестовое полотно сверху покрыто полиэтиленовой пленкой, края которой увязаны проволокой. В пленке выполняют разрез для заливки жидкого азота. Снаружи пленки намотан шнуровой асбест в три слоя для термоизоляции. В разрез вливается жидкий азот. Скорость заливки определяется практически по выбросам жидкого азота из разреза. В начале заливки образуется большое количество газообразного азота из-за высокой температуры вала, поэтому ско- _мрость заливки должна быть меньше. Благодаря наличию листового асбеста, который впитывает жидкий азот, проводя его к тем участ кам вала, куда азот прямо не попадает, в дальнейшем выброс азота прекращается, охлаждение вала происходит более ровно. При появлении изморози на торце вала охлаждение прекращается и производится съем втулки путем приложения осевого усилия. Для съема втулки потребовалось 160 кг жидкого азота. Втулка снята легко без повреждения посадочной поверхности.A -- . The shaft neck in the area of Prp2 ₃ , landing 690 flying to the gear coupling, is covered with a hygroscopic material - asbestos cloth in three layers - over a length of 200 mm. The asbestos cloth on top is covered with a plastic film, the edges of which are tied with wire. An incision is made in the film for pouring liquid nitrogen. Outside the film, three-layer cord asbestos is wound for thermal insulation. Liquid nitrogen is poured into the section. The pouring rate is determined practically by the emissions of liquid nitrogen from the section. At the beginning of pouring a large amount of nitrogen gas from the shaft to the high temperature, so the growth pouring sko- _m should be smaller. Due to the presence of sheet asbestos, which absorbs liquid nitrogen, passing it to those parts of the shaft where nitrogen does not directly enter, further nitrogen emission stops, the shaft is cooled more evenly. When frost appears on the shaft end, cooling stops and the sleeve is removed by applying axial force. To remove the sleeve required 160 kg of liquid nitrogen. The sleeve is removed easily without damaging the seating surface.

Предлагаемый способ по сравнению с прототипом позволяет отбирать тепло со всей поверхности охватываемой детали, что повышает интенсивность процесса охлаждения и сокращает время на охлаждение охватываемой детали, что приводит к повышению эффективности соединения.The proposed method in comparison with the prototype allows you to take heat from the entire surface of the covered part, which increases the intensity of the cooling process and reduces the time for cooling the covered part, which leads to increased efficiency of the connection.

Claims

The invention relates to mechanical engineering, in particular, to assembly and disassembly technology, and can be applied to disassemble connections with guaranteed tension. A known method of disassembling connections with a guaranteed component, which consists in cooling the male component with a cooling medium while insulating its free surface with insulating material. screen 11. A disadvantage of the known method is the need to heat the mating parts, which can lead to undesirable temperature deformations and damage to the connected parts. The purpose of the invention is to improve the quality of disassembly of compounds with guaranteed tension. This goal is achieved by the fact that, according to the disassembly method, which involves cooling the surrounding part with a cooling medium while enclosing its free surface with an insulating screen, a hygroscopic layer is applied onto the free surface of the part covered. material, and an insulating screen is placed on this coating, after which a cooling medium is applied to the coating. FIG. 1 shows the connection of parts before disassembly, general view; in fig. 2 shows section A-A in FIG. 1. The method is carried out as follows. Covered part 1 is covered with absorbent material 2, which is applied to the surface of part 1 adjacent to the mating surfaces of the joint. Thereafter, the hygroscopic material 2 is closed from the external environment with an impermeable screen 3 with a thermal insulating jacket 4. In the screen 3 there is a filling opening 5 into which the refrigerant, liquid nitrogen, is poured. When the temperature at the point of contact of the parts reaches 0 ° C or lower, which is characterized by the appearance of a frost on the male part, on the side opposite to the cooled one, its temperature deformation occurs, which helps to relieve tension on the interface. Example. The method was applied during the dismantling of the gear bushing from the shaft of the hoist 2C-5x2.5. The sleeve is made with an internal diameter of 690 mm and mounted on the shaft A to fit 690. The shaft neck in the zone adjacent to the gear coupling, on a length of 200 mm, is covered with a hygroscopic material - asbestos cloth in three layers. The asbestos cloth on top is covered with plastic wrap, the edges of which are covered with wire. A film is cut to fill with liquid nitrogen. Ishura asbestos was wound in three layers outside the film for thermal insulation. Liquid nitrogen is poured into the incision. The pouring rate is determined practically from the emissions of liquid nitrogen from the section. At the beginning of the casting, a large amount of nitrogen gas of the high temperature of the shaft is formed, therefore the rate of filling should be less. Due to the presence of sheet asbestos, which absorbs liquid nitrogen, its wire to those parts of the shaft where the nitrogen does not directly fall, then the emission of nitrogen stops, the cooling of the shaft occurs more smoothly. When frost develops at the shaft end, the cooling stops and the sleeve is removed by applying axial force. It took 160 kg of liquid nitrogen to remove the sleeve. The sleeve is easily removed without damage to the surface. The proposed method, in comparison with the prototype, allows heat to be collected from the entire surface of the male part, which increases the intensity of the cooling process and reduces the cooling time of the male part, which leads to an increase in the efficiency of the joint. Claims The method of disassembling compounds with a guaranteed tension, which consists in cooling the covered part with a cooling medium while enclosing its free surface with an insulating screen, characterized in that, in order to increase the quality of disassembly, a hygroscopic material is applied to the free surface of the covered part, and an insulating screen is installed on this coating; after which the coating is fed to the cooling medium. . Sources of information taken into account in the examination 1. USSR author's certificate number 701753, cl. In 23 R 11/02, 1980 (prototype).

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