Method for making hot deformed and conversion mean- and large-diameter tubes of corrosion resistant hard-to-form steels and alloys in tube rolling aggregate with pilger mills

IPC classes for russian patent Method for making hot deformed and conversion mean- and large-diameter tubes of corrosion resistant hard-to-form steels and alloys in tube rolling aggregate with pilger mills (RU 2247612):

B21B21 - Pilgrim-step tube-rolling

Another patents in same IPC classes:

Method for preparing rolls of pilger mills for hot rolling of tubes / 2246364

Method comprises steps of mechanically working portion of roll in roll-turning machine tool with use of contour follower for surfacing it with overlap 5 - 10° to side of cold portion from zero point and from angle of lengthwise outlet; under-flux surfacing working portion with wear-resistant refractory steel layer having allowance for mechanical working; mechanically working rolls with use of contour follower until their ready size and grinding working surface. Mechanical working of rolling portion of roll after surfacing is performed along portion from 0.25 - 0.30 of striker length until end of angle of lengthwise outlet adjoined to polishing portion. Grinding of polishing portion and of 0.25 - 0.30 of angle of lengthwise outlet adjoined to polishing portion is realized. Mechanical working of rolling portion of roll for surfacing from zero point until 0.25 -0.30 of striker portion is performed while taking into account allowance of surfaced layer for finish working.

Method for making hot-deformed seamless large-diameter tubes / 2243837

Method comprises steps of heating ingots and billets until yielding temperature; piercing them to hollow thick-wall sleeves in first skew rolling mill for further expanding to thin-wall sleeves in second skew rolling mill and rolling to large-diameter tubes in plants provided with automatic or pilger mills; piercing ingots and billets to thick-wall sleeves in first piercing mill with working rolls driven to rotation in one side and expanding billets to thin-wall sleeves in second piercing mill with working rolls driven to rotation in opposite side.

Method for making hot-deformed seamless large-diameter tubes / 2243837

Method for preparing rolls of pilger mills for hot rolling of tubes / 2246364

Method for making hot deformed and conversion mean- and large-diameter tubes of corrosion resistant hard-to-form steels and alloys in tube rolling aggregate with pilger mills / 2247612

Method comprises steps of drilling electroslag-refining ingots or billets with diameter 380-500 mm; holding them on grates of furnace at temperature 500-550°C for 70-95 min depending upon diameter of blank; heating up to temperature 1120 - 1140°C at rate 1.4 - 1.5 °C/min; piercing billets for forming sleeves at revolution number of rolling rolls 25 - 40 rev/min on mandrel with diameter providing reduction degree in pilger mill no less than 25 mm; realizing first piercing of electroslag-refining ingots or billets with diameter 460-600 mm in piercing mill at elongation degree 1.2 -1.4 and at revolution number of rolling rolls 15 -25 rev/min; realizing second and next (if necessary) piercing or expanding processes at diameter fit no more than 5.0%, elongation degree 1.4 -1,75 and revolution number of rolls 25 - 50 rev/min; seasoning cold sleeves after their first piercing with diameter 460-600 mm at relation D/S = 3.0 -4.5 on grates at temperature 400-500°C for 50 - 70 min depending upon sleeve diameter and wall thickness; heating sleeves until yielding temperature 1100 - 1260°C at rate 1.6 - 1.8°C/min depending upon kind of steel; uniformly heating sleeves with temperature 600 - 800 C after piercing mill until yielding temperature 1100 - 1260°C at rate 1.7 - 2.0°C/min; before discharging sleeves out of furnace keeping them for 45 -60 min at plasticity temperature while tilting sleeves in 10-15 min by angle 180є. Process of piercing sleeves that begins from gripping ingots or billets until their complete fitting onto mandrel is realized at decreased revolution number of rolling rolls from 25 until 15 rev/min. Stable piercing process is performed is realized at 15 -20 rev/min. At outlet of sleeve revolution number of rolls is increased up to 35 -40 rev/min. Piercing (expanding) process beginning from gripping sleeve until complete fitting of it onto mandrel is realized at decreased revolution number of rolling rolls from 50 until 20 rev/min. Stable expanding process is realized 20-25 rev/min. At outlet of sleeve revolution number of rolls is increased up to 45 - 50. Tubes are rolled in pilger mill at elongation degree μ = 3.0 - 5.0. Invention provides possibility for making high quality hot deformed tubes of large and mean diameters from corrosion resistant hard-to-form steels and alloys in tube rolling aggregates with pilger mills.

Drive system for cold rolling pilger mill / 2247613

Drive system includes rolling stand that may perform reciprocation motion; at least one crank and connecting rod mechanism operated by means of drive unit and having crank arm with balancing weight at least for partially balancing inertia forces created by rolling stand; connecting rod jointly connecting rolling stand and crank arm; at least one arranged eccentrically and driven to rotation counter-balance for balancing inertia forces and (or) moments of inertia. Motion of crank and connecting rod mechanism and counter-balance is synchronized by means of gearing. At least one crank and connecting rod mechanism is provided with single counter-balance. Motion plane of balancing weight of crank and connecting rod mechanism driven to rotation coincides with motion plane of counter-balance driven to rotation. Crank and connecting rod mechanism, counter-balance and drive unit are mutually joined through gearing. Drive unit through said gearing drives shaft joined with counter-balance. Mounted on shaft pinion of said gearing through other gearing drives shaft joined with crank and connecting rod mechanism. Balancing weight or counter-balance is in the form of eccentrically arranged mass of one gear wheel of gearing.

Drive system of rolling mill / 2247614

Drive system includes at least one rolling stand mounted with possibility of reciprocation motion; at least one crank and connecting rod mechanism having crank arm with balancing weight at least for partially compensating inertia forces of rolling stand; drive unit and connecting rod jointly connecting rolling stand and crank arm; at least one counter-balance mounted with possibility of eccentric rotation in order to compensate inertia forces and (or) moments of inertia. In order to provide effective compensation of inertia forces in simplified drive system, at least one counter-balance is mounted with possibility of driving it to rotation by means of autonomous drive unit isolated from drive unit of crank and connecting rod mechanism. Said autonomous drive unit of counter-balance acts in rotation direction opposite to rotation direction of crank arm. Mass values of mass of rolling stand, balancing weight, counter-balance are selected in such a way that to compensate as possible first-order components of inertia forces of rolling stand at operation of drive system. System is provided with unit for controlling or regulating autonomous drive unit depending upon angle ϕ₆ and (or) revolution number of crank arm. Rotation center of counter-balance is selected in such a way that including inertia forces of rolling stand and (or) balancing weight moments of inertia of all masses of drive system are at least significantly compensated.

Method for making conversion tubes of low-ductility boron-containing steel / 2255820

Method comprises steps of drilling ingots of electroslag refining, heating them till ductility temperature, piercing in piercing mill for making sleeves; rolling sleeves in pilger mill to tube-blanks, cooling, repairing, cutting tube-blanks by two blanks, heating them up to ductility temperature, piercing-rolling in piercing mill and rolling conversion tubes in pilger mill. Ingots of electroslag refining with diameter 460 - 480 mm are drilled from their bottom end along length L = H - B, where H - height of ingot, mm; B - under-drilled part of ingot equal to 100 - 120 mm. Then ingots are soaked at temperature 450 - 500°C on grates of heating furnace without tilting for 90 - 120 min; heated till 800 - 850° C at rate 1.8 - 2.0°C/min; then heated up to ductility temperature 1050 - 1090°C at rate 2.1 - 2.2°C/min at tilting in 15 - 20 min and soaked at such temperature for 70 - 80 min at tilting by angle about 180° in 10 -15 min.

Method for making conversion tubes of low-ductility boron-containing steel / 2255820

Roll for die rolling of cone elongated hollow metallic articles / 2255821

Roll for die rolling includes along circle of its barrel round cross section groove with outlets. Length of said groove includes successively arranged striker formed by radius of roll ridge of increased length, having constant angles of cross outlet in one third of striker length and smoothly lowered in its remaining part till outlets of polishing portion ( radius of roll ridge in end of portion with constant value of cross outlet consists 1.3 of radius of roll ridge in the beginning of said portion), polishing portion with constant radius of roll ridge, transition portion and idle portion. Round variable groove pass with cross outlets is arranged along helical line on cylindrical surface of roll with ideal diameter. Number of pitches of helical line is determined as n = (L sin α)/(2πR_r) + B + B_{1 ,} where L - length of cone article, mm; R_r - rolling radius of roll, mm; α -inclination angle of axis of roll grooved pass relative to axis of roll, °; B - length of idle portion at inlet equal to (0.20 - 0.25)n; B₁ -length of idle portion at outlet equal to (0.10 -0.15)n. Semipass of upper roll has left-hand and semipass of lower roll has right-hand direction of helical line or vice versa. Groove of roll is half round one with cross tangential or oval outlets with angles 30 - 32°. Values of said angles are constant ones, they are equal to 30 -35° for central angle and they are smoothly decreased to outlet cross section to 20 - 18°.

Method for making elongated conversion large- and mean- diameter tubes of centrifugally cast hollow billets and electroslag refining ingots of steels for telescopic systems (periscopes of submarines) / 2257271

Method comprises steps of producing centrifugally cast billets, heating them till ductile temperature, rolling in pilger mill to thick-wall tubes with allowance for mechanical working, subjecting tubes to heat treatment. In pilger mill conversion hot rolled tubes are rolled while taking into account 1 - 3 rerolling procedures in cold rolling mills depending upon type of billet and dimension of ready product (length, diameter, wall thickness). Conversion hot rolled tubes are rolled to intermediate and final sizes in cold rolling mills at elongation value μ = 1.2 - 1.55. Centrifugally cast hollow billets and drilled ingots of electroslag refining are soaked on grates of furnace without tilting them at 950 -1000°C for 180 - 300 min of homogenization depending upon diameter and wall thickness. Then centrifugally cast billets are uniformly heated up to 1150 -1200°C at heating rate 2.3 - 2.5° C/min at tilting in periods of 15 - 20 min at total period of heating 8 - 11 hours. Ingots of electroslag refining are heated up to 1200 -1250°C at heating rate 1.8 - 2.0°C/min while tilting them in 20 - 25 min for total heating period 9.5 - 12.5 hours. Large-size billets and ingots are heated for more long periods. Centrifugally cast hollow billets are rolled in pilger mill to hot rolled conversion tubes while taking into account 2 - 3 next rerolling of them in cold rolling mills. Sleeves pierced of ingots are rolled in pilger mill to conversion hot rolled conversion tubes while taking into account 1 - 2 rerolling processes in cold rolling mills. Ingots with diameter up to 500 mm are pierced in skew rolling mill to sleeve at one piercing operation with elongation value μ = 1.2 - 1.4. Ingots with diameter 540 mm and more are pierced at two piercing operations with elongation value μ₁ = 1.2 -1.4 and μ₂ = 1.1 - 1.3 respectively. Conversion elongated cold rolled tubes after rolling them to intermediate size are subjected to austenitization in mode providing temperature of furnace space at time moment of charging in range 1000 - 1100°C, heating according to power of furnace up to 1050 ± 15°C, soaking at such temperature for 1 min per 1 mm of tube wall thickness and cooling in air. Conversion elongated cold rolled tubes of ready size after rolling and austenitization are subjected to heat treatment - tempering in mode providing charging at 700 - 730°C; heating according to power of furnace; soaking at temperature 685 ± 15°C for 5 - 5.5 h; cooling in air.

Method for balancing crank-gear drive motor torque / 2260898

Proposed method that can be used to control systems incorporating frequency converter with off-line voltage inverter and induction motor operating into mechanisms handling alternating cyclic load (deep-well pimps, crank gear drive mechanisms, and the like) involves automatic correction of motor speed as function of voltage deviation in dc current section from maximal permissible value which makes it possible to dispense with energy dissipating and rectifying devices affording recuperation mode.

FIELD: rolled tube production processes and equipment, namely manufacture of hot deformed mean- and large-diameter tubes of corrosion resistant hard-to-form steels and alloys, possibly making tubes in tube rolling aggregates with pilger mills.

SUBSTANCE: method comprises steps of drilling electroslag-refining ingots or billets with diameter 380-500 mm; holding them on grates of furnace at temperature 500-550°C for 70-95 min depending upon diameter of blank; heating up to temperature 1120 - 1140°C at rate 1.4 - 1.5 °C/min; piercing billets for forming sleeves at revolution number of rolling rolls 25 - 40 rev/min on mandrel with diameter providing reduction degree in pilger mill no less than 25 mm; realizing first piercing of electroslag-refining ingots or billets with diameter 460-600 mm in piercing mill at elongation degree 1.2 -1.4 and at revolution number of rolling rolls 15 -25 rev/min; realizing second and next (if necessary) piercing or expanding processes at diameter fit no more than 5.0%, elongation degree 1.4 -1,75 and revolution number of rolls 25 - 50 rev/min; seasoning cold sleeves after their first piercing with diameter 460-600 mm at relation D/S = 3.0 -4.5 on grates at temperature 400-500°C for 50 - 70 min depending upon sleeve diameter and wall thickness; heating sleeves until yielding temperature 1100 - 1260°C at rate 1.6 - 1.8°C/min depending upon kind of steel; uniformly heating sleeves with temperature 600 - 800 C after piercing mill until yielding temperature 1100 - 1260°C at rate 1.7 - 2.0°C/min; before discharging sleeves out of furnace keeping them for 45 -60 min at plasticity temperature while tilting sleeves in 10-15 min by angle 180є. Process of piercing sleeves that begins from gripping ingots or billets until their complete fitting onto mandrel is realized at decreased revolution number of rolling rolls from 25 until 15 rev/min. Stable piercing process is performed is realized at 15 -20 rev/min. At outlet of sleeve revolution number of rolls is increased up to 35 -40 rev/min. Piercing (expanding) process beginning from gripping sleeve until complete fitting of it onto mandrel is realized at decreased revolution number of rolling rolls from 50 until 20 rev/min. Stable expanding process is realized 20-25 rev/min. At outlet of sleeve revolution number of rolls is increased up to 45 - 50. Tubes are rolled in pilger mill at elongation degree μ = 3.0 - 5.0. Invention provides possibility for making high quality hot deformed tubes of large and mean diameters from corrosion resistant hard-to-form steels and alloys in tube rolling aggregates with pilger mills.

EFFECT: reduced metal consumption factor at conversion of electroslag-refining ingot to hot rolled tube, lowered cost of tubes.

5 cl, 1 tbl

The invention relates to pipe production, namely the method of production of hot-deformed according to GOST 9940 pipes of large and medium diameters from corrosion-resistant hard steels and alloys, and can be used in the production of them on pipe installations with piligrimage mills.

In practice, tube production the method of manufacture of pipes of large and medium diameters for pipe installations with piligrimage mills of steel grades AND, 08H10N20T2 comprising heating the hollow (centrifugal casting) billets and rolling on piligrimages mill (TI 158-Trtb-63-98. "The manufacture of seamless hot-rolled pipes of steel grade AND for chemical engineering at TU-3-743-78". T 158 Trtb - 6-94. "The pipes of steel grades 08H10N20T2 and HIT for sliding systems on THE 14-3-1564-88").

The disadvantage of this method is the use of a hollow centrifugal casting billet of low quality due to the lack of technology firmware mills helical rolling of billets with a diameter of more than 460 mm with a high content of CR and Ni, and also because of the low power drive of piercing mill.

When flashing billets with a diameter of more than 460 mm, made of corrosion-resistant hard-steel grades and alloys due to increased deformations under the influence of rustagi the surrounding stresses there are cracks and gaps on the sleeves that leads to marriage and does not allow further processing, and also because of the high loads when flashing to stop the engine of a piercing mill, and the termination process.

Tube production known method of rolling pig pipes at facilities with piligrimage mills from corrosion-resistant hard-steel grades and alloys of type 20×TU-sh size 325×40 mm for the manufacture of water-cooled furnace rollers size 295×22×2750 mm and heat-resistant pipe size 325×12 GOST mm of steel grade 06HN28MDT (EI-943), including drilling and boring bars size 460×1600 mm in diameter 275 and 325+5/-0 mm, heating them to a temperature of plasticity, rolling in piligrimages mill in pipe size 325×40 and 325×25 mm with subsequent turning and boring of pipe with specified geometrical dimensions (Protocol No. 1031 agreed terms of delivery pipes of steel grades 20×TU-sh and 06×NMT from g. and a letter indicating the pilot rolling pig pipe size 325×40 and 335×25 mm).

The disadvantage of this method is the use of counter bullion-sleeves with an inner diameter larger than the diameter of the mandrel at 25-35 mm, because a smaller gap on the inner pipe surface defects are formed in the form of flaws, tightening Doren, even with increased taper, and uh what about the in turn leads to increased consumption of expensive metal.

The closest technical solution is the method of production of pipes made of hard steel grades (Patent No. 2175899 on application No. 99120205 from 23.09.1999 year), including Posad pieces of hard steel and alloys with a diameter of 380-500 mm heating furnace, aging at a temperature of 500-550°for 70-95 minutes depending on the diameter, and then heating to a temperature 1120-1140^oWith speeds of 1.4-1.5 deg/min, firmware billet (ingot ESR) in sleeves size in size in diameter at a speed of rotation of the work rolls 25-40 rpm mandrel diameter, providing a reduction in piligrimages the camp of not less than 25 mm

The disadvantage of this method is the inability firmware mills oblique rolling the sleeves of hard steels and alloys on the mandrel over 250 mm, because of high loads and engine piercing mill is stopped (turned off). From the liner size 460×265 mm, threaded on the mandrel with a diameter of 250 mm, can be laminated pipe with a diameter of 273 mm, with minimum wall thickness of 16-17 mm, and the pipe diameter of 325 mm only with the wall more than 40 mm, because the rolling process on piligrimages the mill must be performed at Dornach not more 239/240 mm

The purpose of the proposed method of production of hot-deformed pipes of large and medium diameters from corrosion-resistant trunade reremix grades of steel and alloys on TPA with piligrimage mills from billets and ingots ESR is good quality pipes according to GOST 9940, pig pipes with diameter up to 500 mm and the lower discharge coefficient of the metal in the repartition of the billet (ingot ESR) - pipe GOST 9940, the ESR ingot - pig tube under HPT for the manufacture of pipes according to GOST 9941 or under machining (turning and boring) technical conditions.

This objective is achieved in that in the known method of production of hot-deformed pipes of large and medium diameters from corrosion-resistant hard steels and alloys on TPA with piligrimage mills, including the drilling of ESR ingots or billets with a diameter of 380-500 mm, the shutter speed on the fly at a temperature of 500-550^oWith over 70-95 minutes depending on the diameter, heated to a temperature of plasticity 1120-1140°With speeds of 1.4-1.5 deg/min, firmware blanks in sleeves size in size in diameter at a speed of rotation of the rolls 25-40 rpm mandrel diameter, providing a reduction in piligrimages the camp of not less than 25 mm, the first firmware of the ESR ingots (billets) in diameter 460-600 mm piercing mill lead with extraction of 1.2 to 1.4 when the speed of rotation of the work rolls 15-25 rpm, and the second and subsequent (if needed) flash (rolling with lifting or tenements in diameter not more than 5.0% and the exhaust 1,5-1,75 when the speed of rotation of the rolls 25-50 rpm, cold liner after the first of the firmware diameter 460-600 mm with the ratio D/S=3,0-4,5 stand on the grate at a temperature of 400-500° C for 50-70 minutes, depending on diameter and wall thickness, then heated to a temperature of plasticity 1100-1260°With speeds of 1.6-1.8 degrees per minute depending on the steel grade and the liner after piercing mill with a temperature of 600-800°With heated uniformly to a temperature plasticity 1100-1260°With a rate of 1.7-2.0 degrees per minute, before issuing from the furnace liner incubated for 45-60 minutes at a temperature of plasticity with the casting-off after 10-15 minutes on the corner ≈ 180°the flashing process, from capture of ESR ingots (billets) to complete the location on the mandrel, lead to a decrease in the speed of the work rolls from 25 to 15, established the flashing process is carried out at 15-20 revolutions per minute, and the output of the tube from a roll speed is increased to 35-40, the flashing process (rolling), from the capture sleeve to complete the location on the mandrel, lead to a decrease in the speed of the work rolls from 50 to 20, the established process of rolling at 20-25 rpm, and the output of the tube from a roll speed is increased to 45-50, rolling pipes on piligrimages mill lead with hood μ=3,0-5,0.

Redistribution of deformation parameters due to double piercing of billets ingots ESR) of corrosion-resistant hard steels and alloys in combination with the technological parameters of the firmware (the coefficients is of itzek, firmware with the rise and Posada on the diameter and speed of rotation of the rolls) allowed to reduce the load on the actuator piercing mill and get sleeves that are needed for rolling pipes according to GOST 9940 size 325×12-15, 351×12-15, 377×15-20 and 426×16-25 mm, pig pipes under chpt. The use of the proposed technological parameters and heating rates allowed us to obtain high-quality liners for further rolling tubes on piligrimages the mill, and the redistribution of strain and temperature parameters between piercing and piligrimage mills to obtain high-quality pipes (without defects in the form of captivity and flaws) on piligrimages mill with the ratio D/S=10-27 according to GOST 9940 and pig under chpt. Thus, the claimed method meets the criteria of the invention of "novelty". The comparison of the proposed solutions (way) not only prototype, but also with other technical solutions in this field of technology is not allowed to reveal in them the features distinguishing the claimed solution to the prototype that allows to conclude that the criterion of "substantial differences".

The method was tested on pipe installation piligrimage mills 8-16" "CHTPZ" by rolling pipe size 377×25,426×24 mm of steel grade 08-12×NT and 325×18, 377×20 mm of steel grade 10×NT.

Comparative data on the firmware of the ESR ingots and hire the e pipes from corrosion-resistant hard steels on TPA 8-16" "CHTPZ" with piligrimage mills on existing and proposed technologies listed in the table. The table shows that the process of firmware on the piercing mill, the engine is 2570 kW, the existing technology is only possible when the firmware of the ESR ingots with a diameter of up to 460 mm mandrel diameter of not more than 250 mm, i.e. with hood μ<1,4. The flashing process of the ESR ingots with a diameter of more than 460 mm mandrel diameter of more than 250 mm is impossible because it exceeded the allowable loads on the actuator piercing mill that causes it to stop and halt the process, i.e. the sealing mandrel in sleeves and final marriage.

On existing technology from ESR ingots size 410×100×1600, 430×100×1600 460×100×1600 mm were laminated pipe size 273×12, 273×30, h mm of steel grade 08-HIT and 273×15 mm of steel grade 10X17H13M2T. Rolling pipe size 273×12 mm on piligrimages mill extracts μ>6,0 leads to the formation of captive and external end-to-end flaws that may be associated with temperature interval, deformation parameters and the coefficient of friction at the boundary of metal-Dorn.

The proposed technology laminated pipes according to GOST 9940 and pig under HPT size 377×25 and 426×24 mm of steel 08-HIT and 325×18, 377×20 mm of steel 10X17H13M2T. Bicycle tube size 377×25 mm of steel AND produced from ingots ESR size 490×100×1600 mm Firmware on the oblique mill rolling is rowdily in two firmware. Heat under the first firmware was produced in accordance with patent No. 2175899. After Posada ESR ingots stood on the fly during 70-95 minutes at a temperature of 500-550°C. Heating to a temperature 1120-1140°conducted with a speed of 1.4-1.5 deg/min, and then the rate of heating was increased. The temperature of the issuance of the ingots from the furnace was 1240-1260°C. the First firmware was produced on the mandrel with a diameter of 225 mm cartridge size 490×240×2000 mm, i.e. the size in size, with hood 1,237. The speed of rotation of the rolls on the piercing mill varied, namely, when the ingot-liner on the mandrel speed rolls smoothly reduced from 25 to 15 revolutions per minute, the established process of flashing led when the speed of the rolls 15-20 revolutions per minute, and the output of the tube from a roll, reducing the load on the mill drive train, the speed of rotation was increased to 35 to 40 revolutions per minute. After flashing sleeves were sent to the stock bars, where they cool down and repaired (if necessary). Under the second firmware (rollers) liners were put in cold oven. Sleeves stood on the fly at a temperature of 400-500°for 50-70 minutes. Heating to a temperature ductility of this steel grade 1240-1260°produced with a speed of 1.6-1.8°in a minute. Before issuing from the oven liner at a temperature plasticity (1240-1260° (C) maintained in the first zone of the furnace within 45-0 minutes with the casting-off after 10-15 minutes on the corner ≈ 180°because the firmware (rolling) of thin-walled shells with non-uniform heating along the section (the perimeter) and the length of the leads to their curvature, which in turn can lead to the impossibility of putting them on the mandrel and rolling the sleeves with a large curvature on piligrimages mill to increased transverse to the varying wall thickness of the pipe. The flashing process (rolling) was performed with the rise of the diameter of 4.1% and an extractor fan μ=1,44 (on request lifting and tenements in diameter ≤5%, and hood μ=1,4-1,75). The speed of rotation of the roll piercing mill varied:from the capture sleeve to the full finding it on the mandrel rotation speed of the rolls was reduced from 45 to 20 revolutions per minute, the established process of rolling conducted at a speed of 20 to 22 revolutions per minute, and the output of the tube from a roll, to keep the temperature of the liner, to reduce the cooling time in their piercing mill, the speed of the rolls was increased to 45-50 (on the application speed when the seed is reduced from 50 to 20 revolutions per minute at a steady 20-25 process, and the output of the tube from a roll speed of the rolls is increased to 45-50 rpm). Thus, the sleeve-billet size 490×240×2000 mm rolled out in a piercing mill in sleeves size 510×365×2880 mm, which on piligrimages mill rolled in pig pipe size 377×25×9000 mm with hood μ=3,6 (on request μ=3,0-5,0). Zam is the amendments to the quality of pipes and geometrical dimensions were not. Pipe rode like a pig for re-rolling mills HPT in pipe size 325×12 mm according to GOST 9941. Pipe after piligrimage mill fully meet the requirements of the pipes of this size according to GOST 9940. On a similar scheme was laminated pipe size 426×24, 325×18 and 377×20 mm. Technological parameters of heating ingots ESR, firmware, heat sleeves, rolling sleeves and rolling tubes on piligrimages the mill shown in the table.

The use of the proposed method has allowed to develop the production of high-quality hot-deformed and pig pipes of large and medium diameters from corrosion-resistant hard-steel grades and alloys pipe Assembly 8-16" with piligrimage mills, significantly reduce the expenditure coefficient of the metal when the redistribution of the ESR ingot is hot rolled pipe, and consequently, to reduce the cost of pipes of this range according to GOST 9940 and pig pipes under HPT according to GOST 9941.

Data on the firmware of the ESR ingots and rolling tubes of corrosion-resistant hard steels on TPA 8-16" "CHTPZ" with piligrimage mills on existing and proposed technologies

1. Method for the production of hot-deformed pipes of large and medium diameters of the corrosion-resistant of tradedeficit the controlled grades of steel and alloys on TPA with piligrimage mills, including the drilling of ESR ingots or billets with a diameter of 380-500 mm, the shutter speed on the fly furnace at a temperature of 500-550^oWith over 70-95 minutes depending on the diameter, heated to a temperature 1120-1140°C with a speed of 1.4-1.5 deg./min, firmware blanks in sleeves size in size in diameter, at speeds of the work rolls 25-40 rpm, mandrel diameter, providing a reduction in piligrimages the camp of not less than 25 mm, wherein the first firmware of the ESR ingots or billets with a diameter of 460-600 mm piercing mill lead with extraction of 1.2 to 1.4 when the speed of rotation of the work rolls 15-25 rpm, and the second and subsequent, if necessary firmware-rolling with the rise or tenements in diameter not more than 5.0% and hood 1,4-1,75 when the speed of rotation of the rolls 25-50 rpm

2. The method according to claim 1, characterized in that the cold liner after the first firmware diameter 460-600 mm with the ratio D/S=3,0-4,5 stand on the grate at a temperature of 400-500°C for 50-70 min depending on diameter and wall thickness, then heated to a temperature of plasticity 1100-1260°C with a speed of 1.6-1.8 °/min depending on the steel grade and the liner after piercing mill with a temperature of 600-800°C is heated uniformly to a temperature of plasticity 1100-1260°C at a rate of 1.7 to 2.0 °/min, and before issuing from the furnace liner incubated for 45-60 min at the temperature of the reservoir is knosti with the casting-off after 10-15 minutes on the corner ≈ 180°.

3. The method according to claim 1, characterized in that the flashing process from capture ESR ingots or billets to the full finding a pot lead with the reduction of speed of the work rolls from 25 to 15, established the flashing process is carried out at 15-20 rpm, and the output of the tube from a roll speed is increased to 35-40.

4. The method according to claim 1, characterized in that the process of piercing-rolling from the capture sleeve to complete the location on the mandrel are decreasing the speed of the work rolls from 50 to 20, the established process of rolling at 20-25 rpm, and the output of the tube from a roll speed is increased to 45-50.

5. The method according to claim 1, characterized in that the tube rolling on piligrimages mill lead with hood μ=3,0-5,0.