RU2542135C2 - Production of tapered long-length metal articles by hot rolling - Google Patents

Abstract

FIELD: process engineering.

SUBSTANCE: invention relates to metallurgy. Forged blanks, continuously cast blanks or ESR ingots-blanks are heated to ductility temperature. First, said ingots are pierced at helical rolling stand. Sleeves are rolled at Pilger mills to thick-wall pipe billets at the mandrel with turn over through 90 degrees at rolls with variable round pass. Pipe billets are heated to ductility temperature and rolled at PRU with Pilger mills at mandrels at rolls with pass coiling to roll axis. Axes of rolls are arranged in parallel in vertical plane. Semi-pass of top roll features LH direction of helix line while that of bottom roll has RH direction, or visa versa. The number of turns is defined subject to metal article length and Pilger mill roll body diameter. Sleeves are rolled at long mandrels of periodical taper at three or 3+n Pilger mills arranged in one line. Passes and roll body diameters of every next mill are decrease while their sizes are defined with allowance for invariable path of metal article rolling-out by every Pilger mill.

EFFECT: higher quality of rolled metal articles.

2 cl, 1 dwg, 1 tbl

Description

The invention relates to metallurgical and rolling industries, and in particular to a method for the production of cone lengthy hollow metal products by hot rolling, with a decrease in diameter and wall thickness from one end to the other, from blanks, NLZ and ingot blanks ESR on new plants with pilgrim mills for long with periodic tapering of mandrels in three or 3 + n stands, located in tandem along one axis.

A known method of manufacturing conical long hollow or solid reinforced concrete products (poles of lighting poles, supports for tensioning and maintaining power cables of tram-trolleybus lines), including the manufacture of a frame from reinforcement, pouring this frame with concrete, drying and transporting them to the place of installation and installation.

The disadvantage of this method is the low productivity, laboriousness of manufacture, increased marriage during transportation and failure during traffic accidents with the failure of power lines and tram-trolleybus power cables.

A known method for the production of conical long hollow metal products, including flaring and butt welding manually several pipe products of different diameters and wall thicknesses.

The disadvantage of this method is also the low productivity, the complexity of manufacturing due to the joining of pipe products of different diameters and wall thicknesses, heating and manual expansion of the joined products, manual welding in conductors with subsequent editing. The technological process of manufacturing these products does not have flow, and therefore has a wide variation in geometric dimensions and quality indicators. Such products do not have an artistic and aesthetic appearance due to the lack of smooth transitions from the base to the top.

A known method for the production of cone lengthy hollow metal products, including drilling in forged blanks, NLZ and ingots, blanks ESR of the Central hole, heating to ductility temperature and forging them on a radial forging machine.

The disadvantage of this method is the low productivity, the complexity of manufacturing and, as a consequence, the increased cost. The manufacturing process, as well as the above analogue, has no threading.

, последовательно сводят на величину δ, передачу заготовок конусных длинномерных полых изделий на шлеппер, охлаждение и передачу в отделку, правку и удаление технологической обрези (Патент RU №2275978, кл. В21В 21/00, 10.05.2006, бюл. №13).In the pipe industry, there is a known method for the production of cone long hollow metal products by hot rolling, including heating the workpieces to ductility temperature, flashing them in cross-screw rolling mills into sleeves, rolling the sleeves in plants with pilgrim or automatic mills into pipes, cutting pipes into measured lengths, rolling in reduction and expansion mills with three or four roll stands until the front end of the conical lengthy hollow product exits the last stand of the reduction and expansion zhnogo mill, inhibition of all stands stretch-reducing mill, issuing preform conical elongated hollow body from the last stand stretch-reducing mill due to reverse to the upstream side during the time t, the rolls of each stand, except the last, during the time t _1, the values of which are determined from expressions: $$\frac{t_{\mathrm{one}}}{t(n-\mathrm{one})}$$

are successively reduced by a value of δ, transferring blanks of cone lengthy hollow products to a slapper, cooling and transferring to finishing, dressing and removal of technological trimmings (Patent RU No. 2275978, class B21B 21/00, 05/10/2006, bull. No. 13).

The disadvantages of this method for the production of long hollow metal products is the absence of reduction and extension (reduction) mills as part of pipe rolling plants with pilgrim mills, and the production of these products on TPU with automatic mills requires the installation of a second reduction mill for their production. Long hollow metal products made from redistribution pipes with a diameter of 250 mm or less will have a small taper, because with an increase in tapering, the upper part of the conical lengthy hollow metal product will have an increased bending ability, which is not permissible in the manufacture of supports for lighting poles, supports for tensioning and maintaining power cables of tram-trolleybus lines. This method is not implemented in an industrial environment.

The closest technical solution is a method for the production of conical long hollow metal products by hot rolling and a device for its implementation (Patent RU No. 2268796, CL 21/21, 01/27/2006, bull. No. 3). A method for the production of conical long hollow metal products by hot rolling, including heating the billet pipes to a temperature of plasticity and rolling them in plants with pilgrim mills on a long conical mandrel in rolls, the caliber of which is made along a helical line to the axis of the rolls, and the axis of the rolls are parallel in vertical planes, a half-gauge on the upper roll is made with left-hand, and on the lower with right-hand direction of the helix or vice versa, the number of turns of a round variable caliber with kami is determined from the expression

$$n=\frac{L\sin \alpha }{2\pi R_k}$$

where L is the length of the conical hollow product, mm; R _k is the rolling radius of the roll, mm; α is the angle of inclination of the axis of the caliber to the axis of the roll, deg., reciprocating movement of the feeding apparatus in the horizontal plane synchronously to the rotation of the rolls by an amount determined by the formula

$$N=n\frac{D_{\max }+D_{\min }}{2}+K(n-\mathrm{one})$$

where n is the number of turns of caliber along the length of the roll, pcs .; D _max - the maximum diameter of the caliber, mm; D _min - the minimum diameter of the caliber, mm; K is the width of the roll flanges between calibers, mm, rolling in rolls with sliding bearings, the movement of the rolls in the horizontal plane due to rolling forces or forced horizontal movement from a separate drive operating synchronously with the speed of rotation of the rolls, and the rolls return to their original position when rolling for due to the reverse rotation of the rolls from the main drive or forced horizontal movement from a separate drive.

Installation of a pilgrim mill with a gear stand, connecting spindles, couplings and work rolls for the production of long conical hollow metal products, the couplings of which and the drive necks of the work rolls are made in the form of telescopic systems with the movement of the rolls in the horizontal plane by an amount determined by the formula

$$N=n\frac{D_{\max }+D_{\min }}{2}+K(n-\mathrm{one})$$

the feeding apparatus is located at an angle α to the horizontal axis of the rolls, and the diameters of the conical mandrel are equal to the internal diameters of the base and top of the long conical product, the cone of the mandrel exceeds the conicity of the long conical hollow product by the total amount of drawing when rolling a cylindrical pipe into a long conical hollow product Σµ, and the length less in Σµ, which are determined by the formulas α ₀ = α _u Σµ, $$L_0=\frac{L}{\Sigma \mu }$$

where α ₀ is the taper angle of the mandrel, deg .; α _u - taper angle of the product, degrees .; Σµ is the total drawing coefficient when rolling a cylindrical pipe into a conical long hollow product; L is the length of the conical product, mm The disadvantage of this method of manufacturing conical long hollow metal products by hot rolling and a device for its implementation (prototype) is that this device is difficult to manufacture and at the moment it is not implemented anywhere. This is due to the fact that for the production of conical long hollow metal products according to this method and device, multi-groove rolls with a decreasing caliber from beginning to end are required. The gauge must be performed along a helix with an angle of inclination of the axis of the gauge to the axis of the roll, which, in turn, will lead to an increase in the length of the rolls. For the manufacture of multi-groove rolls, the caliber of which is made on a helical line, at the moment there is no machine equipment. The location of the feed apparatus at an angle to the horizontal axis of the rolls, equal to the angle of inclination of the caliber axis to the axis of the rolls, and the reciprocating movement of the rolls or feed apparatus entails the design, manufacture and commissioning of a fundamentally new installation (pilgrim mill) that is difficult to manufacture and operate.

The objective of the proposed method for the production of conical long hollow metal products by hot rolling is the industrial line production of these products having an aesthetic appearance, safety margin with a significant reduction in their weight, reducing their cost and replacing reinforced concrete products with economically and aesthetically competing durable lightweight metal products.

, где К_ср.=1,15-1,2 - средний коэффициент опережения по всей дуге рабочей части пилигримового валка; R_o - значение радиуса валка в нулевой точке, мм; R_n - значение радиуса валка на полирующем участке, мм; Θ_б - значение центрального угла бойка валка, рад; Θ_n - значение центрального угла полирующего участка валка, рад; l_m - путь торможения подающего аппарата, мм, а геометрические размеры гильз для прокатки конусных длинномерных полых металлических изделий в трех пилигримовых клетях определяют из выражения:The technical result is achieved by the fact that in the known method for the production of conical long hollow metal products by hot rolling, including heating forged billets, continuously cast billets or ingots-billets of electroslag remelting to a plasticity temperature, piercing them in cross-helical rolling mills into sleeves, rolling sleeves on pilgrim mills in thick-walled billet pipes with a long mandrel with periodic feeding and tilting at an angle equal to ≈90 ° in rolls having a variable round caliber with outlets, heating the billet pipes to a temperature of plasticity, rolling them in plants with pilgrim mills on a long conical mandrel in rolls, the caliber of which is made along a helical line to the axis of the rolls, and the axis of the rolls are parallel in the vertical plane, the half-gauge on the upper roll is made with left-side and on the bottom - with the right-hand direction of the helix or vice versa, while the number of turns is determined depending on the length of the conical lengthy hollow metal product and the diameter of the barrel rolls pilig rim mill, characterized in that the rolling of sleeves is carried out on long, periodically tapering mandrels in three or 3 + n pilgrim stands, which are arranged on the same axis, while the calibers and diameters of the roll barrels of each subsequent stand are reduced, and their geometric dimensions are determined with taking into account the conditions for the constancy of the rollback path of a conical long hollow metal product by each pilgrim stand, expressed by the following relationship: $$L_{\mathrm{about}t\mathrm{to}.}={\mathrm{TO}}_{\mathrm{from}R.}\left[\left(\frac{R_o+R_n}{2}\right){\Theta }_b+R_n{\Theta }_n\right]+l_m$$

where K _cf. = 1.15-1.2 - the average coefficient of advance along the entire arc of the working part of the pilgrim roll; R _o - the radius of the roll at the zero point, mm; R _n - the radius of the roll on the polishing section, mm; Θ _b - the value of the central angle of the roll head, rad; Θ _n is the value of the central angle of the polishing portion of the roll, rad; l _m is the braking path of the feeding apparatus, mm, and the geometric dimensions of the sleeves for rolling conical long hollow metal products in three pilgrim stands are determined from the expression:

,

,

and in 3 + n stands from the expression:

,

,

where L ₁ - the length of the base of the conical long hollow metal product, mm; L _P.G. - the length of the base of the conical long hollow metal products for the formation of the pilgrim head (technological trim), mm; D ₁ - the diameter of the base conical long hollow metal product, mm; S ₁ - wall thickness of the base of the conical long hollow metal product, mm; L ₂ - the length of the conical lengthy hollow metal products adjacent to the base, mm; S ₂ - wall thickness of the conical lengthy hollow metal product adjacent to the base, mm; L ₃ - the length of the top of the conical long hollow metal product when rolling in three pilgrim stands, mm; S ₃ - wall thickness of the top of the conical long hollow metal product when rolling in three pilgrim stands, mm; L _n-1 - the length of the plot n-1 conical long hollow metal product when rolling in 3 + n pilgrim stands, mm; L _n - the length of the top of the conical long hollow metal product when rolling in 3 + n pilgrim stands, mm; S _n-1 is the wall thickness of the section n-1 of a conical long hollow metal product when rolling in 3 + n pilgrim stands, mm; S _n - wall thickness of the top of the conical lengthy hollow metal product when rolling in 3 + n pilgrim stands, mm; L _puff. - the length of the top of the conical lengthy hollow metal product for forming a seed end (technological trim; D _g is the diameter of the sleeve for the manufacture of the conical long hollow metal product, mm; S _g is the wall thickness of the sleeve for the manufacture of the conical long hollow metal product, mm

, где К_ср.=1,15-1,2 - средний коэффициент опережения по всей дуге рабочей части пилигримового валка; R_o - значение радиуса валка в нулевой точке, мм; R_n - значение радиуса валка на полирующем участке, мм; Θ_б - значение центрального угла бойка валка, рад; Θ_n - значение центрального угла полирующего участка валка, рад; l_m - путь торможения подающего аппарата, мм, а геометрические размеры гильз для прокатки конусных длинномерных полых металлических изделий в трех пилигримовых клетях определяют из выражения:A comparative analysis of the proposed solution with the prototype shows that the inventive method for the production of cone lengthy hollow metal products by hot rolling differs from the known one in that the sleeves are rolled on long mandrels with periodic tapering in three or 3 + n pilgrim stands, which are arranged on one axis, at the same time, the calibers and diameters of the roll barrels of each subsequent stand are reduced, and their geometrical dimensions are determined taking into account the condition of constancy of the rollback roll cone length a single metal product with each pilgrim stand, expressed by the following relationship: $$L_{\mathrm{about}t\mathrm{to}.}={\mathrm{TO}}_{\mathrm{from}R.}\left[\left(\frac{R_o+R_n}{2}\right){\Theta }_b+R_n{\Theta }_n\right]+l_m$$

where K _cf. = 1.15-1.2 - the average coefficient of advance along the entire arc of the working part of the pilgrim roll; R _o - the radius of the roll at the zero point, mm; R _n - the radius of the roll on the polishing section, mm; Θ _b - the value of the central angle of the roll head, rad; Θ _n is the value of the central angle of the polishing portion of the roll, rad; l _m is the braking path of the feeding apparatus, mm, and the geometric dimensions of the sleeves for rolling conical long hollow metal products in three pilgrim stands are determined from the expression:

,

,

and in 3 + n stands from the expression:

,

,

where L ₁ - the length of the base of the conical long hollow metal product, mm; L _P.G. - the length of the base of the conical long hollow metal products for the formation of the pilgrim head (technological trim), mm; D ₁ - the diameter of the base conical long hollow metal product, mm; S ₁ - wall thickness of the base of the conical long hollow metal product, mm; L ₂ - the length of the conical lengthy hollow metal products adjacent to the base, mm; S ₂ - wall thickness of the conical lengthy hollow metal product adjacent to the base, mm; L ₃ - the length of the top of the conical long hollow metal product when rolling in three pilgrim stands, mm; S ₃ - wall thickness of the top of the conical long hollow metal product when rolling in three pilgrim stands, mm; L _n-1 - the length of the plot n-1 conical long hollow metal product when rolling in 3 + n pilgrim stands, mm; L _n - the length of the top of the conical long hollow metal product when rolling in 3 + n pilgrim stands, mm; S _n-1 is the wall thickness of the section n-1 of a conical long hollow metal product when rolling in 3 + n pilgrim stands, mm; S _n - wall thickness of the top of the conical lengthy hollow metal product when rolling in 3 + n pilgrim stands, mm; L _puff. - the length of the top of the conical lengthy hollow metal products for the formation of the seed end (technological trim), mm; D _g - the diameter of the sleeve for the manufacture of conical long hollow metal products, mm; S _g - wall thickness of the sleeve for the manufacture of a conical long hollow metal product, mm Thus, these differences allow us to conclude that the criterion of "inventive step" is met.

Comparison of the proposed method not only with the prototype, but also with other technical solutions in the art did not allow them to identify signs that distinguish the claimed solution from the prototype, which corresponds to the patentability "inventive step".

, где µ - коэффициент вытяжки при прошивке заготовок диаметром 600 мм в гильзы размером 600×вн.310×2500 мм. Коэффициент вытяжки определяем по формуле: $$\mu =\frac{R_{з}^2К}{(D_{г}-S_{г})S_{г}}$$

, где R_з - радиус заготовки, мм; К=0,97 - коэффициент, учитывающий угар металла при нагреве заготовок в методических печах до температуры пластичности.Since there is no similar method and equipment in world practice, it is not possible to give an example of a concrete implementation in a given period of time. Instead of an example of a specific implementation, the technological sequence of operations for the production of conical long hollow metal products by hot rolling of 426 × 70 × 3500 + 325 × 25 × 3500 + 273 × 10 × 8000 mm in size is given. According to paragraph 2 of the claims, we determine the geometric dimensions of the liner required for the production of conical long hollow metal products. The size of the sleeve will be 600 × ext. 310 × 2500 mm. This sleeve size can be obtained from a workpiece with a diameter of 600 mm. Knowing the size of the liner, we determine the size of the initial blanks by the formula: $$L_{s\mathrm{but}g.}=\frac{L_g}{\mu }$$

, where µ is the drawing coefficient when piercing blanks with a diameter of 600 mm into sleeves 600 × in. 310 × 2500 mm in size. The hood coefficient is determined by the formula: $$\mu =\frac{R_s^2\mathrm{TO}}{(D_g-S_g)S_g}$$

where R _z is the radius of the workpiece, mm; K = 0.97 is a coefficient that takes into account the burning of metal during heating of workpieces in methodical furnaces to the ductility temperature.

, получим, что для производства конусных длинномерных полых металлических изделий горячей прокаткой размером 426×70×3500+325×25×3500+273×10×8000 мм необходимы заготовки размером 600×1825±25 мм. Зная размер заготовок, садим их в печь и нагреваем до температуры пластичности, выдаем из печи и прошиваем в стане поперечно-винтовой прокатки на оправке диаметром 295 мм в гильзы размером 600×вн.310×2500 мм. Гильзы передаем на входную сторону первой пилигримовой клети с диаметром бочки валков 1045 мм. Подающий аппарат имеет только первая пилигримовая клеть. Вторая клеть с диаметром бочки валков 945 мм, а третья клеть с диаметром бочки 870 мм. Клети установлены в потоке последовательно (тандемом) с расстоянием между осями 3500 мм. Валки каждой клети вращаются синхронно, верхние по часовой стрелке, а нижние против часовой стрелки. Прокатку конусных длинномерных полых металлических изделий производят на дорне, которые подающим аппаратом первой клети вводятся в гильзу. Подставляя данные, получим геометрические размеры дорнов, которые приведены в таблице. После введения дорна в гильзу начинается процесс затравки ее первой клетью и прокатка горячекатаной трубы размером 426×70 мм в валках с диаметром бочки 1045 мм в калибре 434 мм с поворотом гильзы-трубы подающим аппаратом на угол равный ≈90°. По мере прокатки передний конец трубы размером 426×70 мм входит в валки второй клети с диаметром бочки 945 мм и с калибром 332 мм. Производится затравка переднего конца и прокатка трубы размером 325×25 мм. По мере прокатки передний конец трубы размером 325×25 мм входит в валки третьей клети с диаметром бочки 870 мм и с калибром 280 мм. Производится затравка переднего конца и прокатка трубы размером 273×10 мм. Валки каждой клети имеют индивидуальный привод и вращаются синхронно, т.е. нулевые точки валков каждой клети входят в контакт с металлом конусного изделия в одно и то же время. Для получения геометрических размеров конусных длинномерных полых металлических изделий процесс прокатки необходимо вести, чтобы пути откатов каждой клети были равными. Данные значений путей отката каждой клети приведены в таблице. Из таблицы видно, что при прокатке в валках с диаметрами бочек 1045, 945 и 870 мм и с врезанными в них калибрами размером 434, 332 и 280 мм, пути откатов будут равными 1130, 1130 и 1110 мм. Принципиальная схема производства конусных длинномерных полых металлических изделий в трех клетях пилигримового стана приведена на фиг. 1. После последней подачи гильзы - конусного изделия в очаг деформации каждой клети производят, в зависимости от геометрических размеров готовых изделий, одну или две кантовки конусной оправки (дорна) 1 с раскатанным горячедеформированным конусным длинномерным полым изделием 5, чтобы раскатать бунт от последней подачи и придать изделию расчетные геометрические формы и параметры. После завершения цикла прокатки верхние валки каждой клети 2, 3 и 4 поднимают. Подающим аппаратом первой клети (на фиг. 1 не показан) дорн извлекают из конусного длинномерного полого изделия. Дорн (длинномерную оправку) охлаждают или заменяют на охлажденную. Поднимают выводящие ролики рольганга, установленные после каждой клети, и выводят изделие из клетей на приемный желоб, по которому оно подается к пилам ударного действия. Удаляют технологические отходы (затравочный конец и пилигримовую головку). После удаления технологических отходов конусные длинномерные полые изделия 5 поступают в отделение отделки, где производят подрезку концов, правку, покраску, приемку на соответствие НТД, складирование и отгрузку потребителю.Substituting data in the formula $$L_{s\mathrm{but}g.}=\frac{L_g}{\mu }$$

, we get that for the production of conical long hollow metal products by hot rolling of size 426 × 70 × 3500 + 325 × 25 × 3500 + 273 × 10 × 8000 mm, workpieces with a size of 600 × 1825 ± 25 mm are required. Knowing the size of the billets, we put them in the furnace and heat to the temperature of plasticity, we let them out of the furnace and we sew them in a cross-screw mill on a mandrel with a diameter of 295 mm in sleeves 600 × in. 310 × 2500 mm in size. The sleeves are transferred to the input side of the first pilgrim stand with a roll barrel diameter of 1045 mm. The feeding apparatus has only the first pilgrim stand. The second stand with a roll barrel diameter of 945 mm, and the third stand with a barrel diameter of 870 mm. The cages are installed in the flow in series (tandem) with a distance between the axles of 3500 mm. The rolls of each stand rotate synchronously, the upper counterclockwise and the lower counterclockwise. Cone long hollow metal products are rolled on a mandrel, which is introduced into the sleeve by the feeding apparatus of the first stand. Substituting the data, we obtain the geometric dimensions of the mandrels, which are given in the table. After the mandrel is inserted into the sleeve, the process of inoculating it with the first stand begins and the hot-rolled pipe is sized 426 × 70 mm in rolls with a barrel diameter of 1045 mm in the caliber 434 mm with rotation of the sleeve-pipe by the feeding apparatus by an angle equal to ≈90 °. As rolling, the front end of the pipe measuring 426 × 70 mm enters the rolls of the second stand with a barrel diameter of 945 mm and a caliber of 332 mm. The front end is seeded and the pipe is sized 325 × 25 mm. As rolling, the front end of the pipe measuring 325 × 25 mm enters the rolls of the third stand with a barrel diameter of 870 mm and a caliber of 280 mm. Seeding of the front end and rolling of a pipe measuring 273 × 10 mm is performed. The rolls of each stand are individually driven and rotate synchronously, i.e. the zero points of the rolls of each stand come into contact with the metal of the conical product at the same time. To obtain the geometric dimensions of the conical long hollow metal products, the rolling process must be carried out so that the rollback paths of each stand are equal. The data of the rollback path values of each stand are given in the table. It can be seen from the table that when rolling in rolls with barrels with diameters of 1045, 945 and 870 mm and with caliber 434, 332 and 280 mm embedded in them, the rollback paths will be 1130, 1130 and 1110 mm. A schematic diagram of the production of conical long hollow metal products in three stands of a pilgrim mill is shown in FIG. 1. After the last feed of the sleeve - conical product into the deformation zone of each stand, depending on the geometrical dimensions of the finished products, one or two tilts of the conical mandrel (mandrel) 1 are produced with a rolled hot-deformed conical long-length hollow product 5 to roll out the riot from the last supply and give the product calculated geometric shapes and parameters. After the rolling cycle is completed, the upper rolls of each stand 2, 3 and 4 are raised. The feeding apparatus of the first stand (not shown in FIG. 1), the mandrel is removed from the conical lengthy hollow product. The mandrel (long mandrel) is cooled or replaced with a chilled one. The output rollers of the roller table installed after each stand are lifted, and the product is taken out of the stands to a receiving chute through which it is fed to the impact saws. Process waste (seed end and pilgrim head) is removed. After the technological waste is removed, the conical long hollow products 5 go to the finishing department, where they trim the ends, dress, paint, accept the NTD for compliance, store and ship to the consumer.

Using the proposed method for the production of long conical hollow metal products, in comparison with existing methods, will significantly increase productivity, reduce metal consumption, reduce costs and for the first time in the world practice carry out industrial flow production of high-quality, with given geometric parameters, products, ensure the need of the country's national economy, to produce competitive products and export them to other countries of the world.

Claims (2)

1. A method for the production of conical long hollow metal products by hot rolling, including heating forged billets, continuously cast billets or electroslag ingots-billets to a plasticity temperature, piercing them in transverse helical mills into sleeves, rolling sleeves on pilgrim mills into thick-walled blanks on a mandrel with periodic feeding and tilting at an angle equal to 90 ° in rolls having a variable round caliber with outlets, heating the workpieces to a ductility temperature, about roll them in installations with pilgrim mills on a mandrel in rolls, the caliber of which is made along a helical line to the axis of the rolls, the axis of the rolls is parallel in the vertical plane, the half-gauge on the upper roll is left-handed, and on the lower - with the right-hand helical direction or vice versa the number of turns is determined depending on the length of the conical lengthy hollow metal product and the diameter of the barrel rolls of the pilgrim mill, characterized in that the sleeves are rolled on long mandrels x, with periodic taper, in three or 3 + n pilgrim stands, which are located on one axis, while the calibers and diameters of the roll barrels of each subsequent stand are reduced, and their geometric dimensions are determined taking into account the condition of the constancy of the rollback path of the long conical hollow metal product of each pilgrim stand, expressed by the following relationship:
$$L_{\mathrm{about}t\mathrm{to}.}={\mathrm{TO}}_{\mathrm{from}R.}\left[\left(\frac{R_o+R_P}{2}\right){\Theta }_b+R_P{\Theta }_P\right]l_t,$$

where k _cp. = 1.15-1.2 - the average coefficient of advance along the entire arc of the working part of the pilgrim roll;
R _o - the radius of the roll at the zero point, mm;
R _p - the radius of the roll on the polishing section, mm;
Θ _b - the value of the central angle of the roll head, rad;
Θ _p - the value of the Central angle of the polishing section of the roll, rad;
l _t - braking path of the feeding apparatus, mm 2. The method according to claim 1, characterized in that the geometric dimensions of the sleeves for rolling cone lengthy hollow metal products in three pilgrim stands are determined from the expression:
$$L_g=\frac{(L_{\mathrm{one}}+L_{P.g.})(D_{\mathrm{one}}-S_{\mathrm{one}})S_{\mathrm{one}}+L_2(D_2-S_2)S_2+(L_3+L_{s\mathrm{but}t.})(D_3-S_3)S_3}{(D_g-S_g)S_g}$$

,
and in 3 + n pilgrim stands from the expression:
$$L_g=\frac{(L_{\mathrm{one}}+L_{P.g.})(D_{\mathrm{one}}-S_{\mathrm{one}})S_{\mathrm{one}}+L_2(D_2-S_2)S_2+L_3(D_3-S_3)S_3+--+L_{n-\mathrm{one}}(D_{n-\mathrm{one}}-S_{n-\mathrm{one}})S_{n-\mathrm{one}}+(L_n+L_{s\mathrm{but}t.})(D_n-S_n)S_n}{(D_g-S_g)S_g}$$

,
where L ₁ - the length of the base of the conical long hollow metal product, mm;
L _P.G. - the length of the base of the conical long hollow metal products for the formation of the pilgrim head as a technological trim, mm;
D ₁ - the diameter of the base conical long hollow metal product, mm;
S ₁ - wall thickness of the base of the conical long hollow metal product, mm;
L ₂ - the length of the conical lengthy hollow metal products adjacent to the base, mm;
S ₂ - wall thickness of the conical lengthy hollow metal product adjacent to the base, mm;
L ₃ - the length of the top of the conical long hollow metal product when rolling in three pilgrim stands, mm;
S ₃ - wall thickness of the top of the conical long hollow metal product when rolling in three pilgrim stands, mm;
L _n-1 - the length of the plot n-1 conical long hollow metal product when rolling in 3 + n pilgrim stands, mm;
L _n - the length of the top of the conical long hollow metal product when rolling in 3 + n pilgrim stands, mm;
S _n-1 is the wall thickness of the section n-1 of a conical long hollow metal product when rolling in 3 + n pilgrim stands, mm;
S _n - wall thickness of the top of the conical lengthy hollow metal product when rolling in 3 + n pilgrim stands, mm;
L _puff. - the length of the top of the conical lengthy hollow metal product for forming a seed end as a technological trim, mm;
D _g - the diameter of the sleeve for the manufacture of conical long hollow metal products, mm;
S _g - wall thickness of the sleeve for the manufacture of a conical long hollow metal product, mm