EP1872878B1 - Process for producing seamless tube - Google Patents
Process for producing seamless tube Download PDFInfo
- Publication number
- EP1872878B1 EP1872878B1 EP06730876A EP06730876A EP1872878B1 EP 1872878 B1 EP1872878 B1 EP 1872878B1 EP 06730876 A EP06730876 A EP 06730876A EP 06730876 A EP06730876 A EP 06730876A EP 1872878 B1 EP1872878 B1 EP 1872878B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- water
- mandrel bar
- liquid
- coating
- rolling
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Ceased
Links
- 238000000034 method Methods 0.000 title abstract description 14
- 239000011248 coating agent Substances 0.000 claims abstract description 77
- 238000000576 coating method Methods 0.000 claims abstract description 77
- 239000007788 liquid Substances 0.000 claims abstract description 76
- 238000005096 rolling process Methods 0.000 claims abstract description 48
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 46
- 238000001816 cooling Methods 0.000 claims abstract description 34
- 239000000314 lubricant Substances 0.000 claims description 86
- 238000004519 manufacturing process Methods 0.000 claims description 32
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical group [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 23
- 239000007787 solid Substances 0.000 claims description 23
- 229910002804 graphite Inorganic materials 0.000 claims description 22
- 239000010439 graphite Substances 0.000 claims description 22
- 239000010445 mica Substances 0.000 claims description 21
- 229910052618 mica group Inorganic materials 0.000 claims description 21
- 229920005989 resin Polymers 0.000 claims description 20
- 239000011347 resin Substances 0.000 claims description 20
- 239000000463 material Substances 0.000 claims description 12
- 239000000203 mixture Substances 0.000 claims description 10
- 239000010935 stainless steel Substances 0.000 claims description 10
- 229910001220 stainless steel Inorganic materials 0.000 claims description 10
- 229910000851 Alloy steel Inorganic materials 0.000 claims description 9
- 229910052700 potassium Inorganic materials 0.000 claims description 8
- 239000011591 potassium Substances 0.000 claims description 8
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 claims description 6
- 239000006185 dispersion Substances 0.000 claims description 6
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 claims description 5
- 239000007864 aqueous solution Substances 0.000 claims description 5
- AGLSQWBSHDEAHB-UHFFFAOYSA-N azane;boric acid Chemical compound N.OB(O)O AGLSQWBSHDEAHB-UHFFFAOYSA-N 0.000 claims description 5
- MEFBJEMVZONFCJ-UHFFFAOYSA-N molybdate Chemical compound [O-][Mo]([O-])(=O)=O MEFBJEMVZONFCJ-UHFFFAOYSA-N 0.000 claims description 5
- 229910052708 sodium Inorganic materials 0.000 claims description 5
- 239000011734 sodium Substances 0.000 claims description 5
- 239000012466 permeate Substances 0.000 claims description 4
- WUUHFRRPHJEEKV-UHFFFAOYSA-N tripotassium borate Chemical compound [K+].[K+].[K+].[O-]B([O-])[O-] WUUHFRRPHJEEKV-UHFFFAOYSA-N 0.000 claims description 4
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 claims description 2
- 238000001035 drying Methods 0.000 description 18
- 238000005461 lubrication Methods 0.000 description 14
- 238000012360 testing method Methods 0.000 description 9
- 238000011156 evaluation Methods 0.000 description 8
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- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 4
- 229910000831 Steel Inorganic materials 0.000 description 4
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 4
- -1 dimethyl siloxane Chemical class 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 238000010438 heat treatment Methods 0.000 description 4
- BWHMMNNQKKPAPP-UHFFFAOYSA-L potassium carbonate Chemical compound [K+].[K+].[O-]C([O-])=O BWHMMNNQKKPAPP-UHFFFAOYSA-L 0.000 description 4
- 238000005507 spraying Methods 0.000 description 4
- 239000010959 steel Substances 0.000 description 4
- 229910045601 alloy Inorganic materials 0.000 description 3
- 239000000956 alloy Substances 0.000 description 3
- 239000002270 dispersing agent Substances 0.000 description 3
- 229910000027 potassium carbonate Inorganic materials 0.000 description 3
- 229910000029 sodium carbonate Inorganic materials 0.000 description 3
- 239000011684 sodium molybdate Substances 0.000 description 3
- 235000015393 sodium molybdate Nutrition 0.000 description 3
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
- XTXRWKRVRITETP-UHFFFAOYSA-N Vinyl acetate Chemical class CC(=O)OC=C XTXRWKRVRITETP-UHFFFAOYSA-N 0.000 description 2
- RJDOZRNNYVAULJ-UHFFFAOYSA-L [O--].[O--].[O--].[O--].[O--].[O--].[O--].[O--].[O--].[O--].[F-].[F-].[Mg++].[Mg++].[Mg++].[Al+3].[Si+4].[Si+4].[Si+4].[K+] Chemical compound [O--].[O--].[O--].[O--].[O--].[O--].[O--].[O--].[O--].[O--].[F-].[F-].[Mg++].[Mg++].[Mg++].[Al+3].[Si+4].[Si+4].[Si+4].[K+] RJDOZRNNYVAULJ-UHFFFAOYSA-L 0.000 description 2
- 239000004599 antimicrobial Substances 0.000 description 2
- 229910052593 corundum Inorganic materials 0.000 description 2
- SZVJSHCCFOBDDC-UHFFFAOYSA-N ferrosoferric oxide Chemical compound O=[Fe]O[Fe]O[Fe]=O SZVJSHCCFOBDDC-UHFFFAOYSA-N 0.000 description 2
- 239000012535 impurity Substances 0.000 description 2
- 230000035699 permeability Effects 0.000 description 2
- 229910052628 phlogopite Inorganic materials 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- 238000003860 storage Methods 0.000 description 2
- 125000000391 vinyl group Chemical group [H]C([*])=C([H])[H] 0.000 description 2
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- 229920003169 water-soluble polymer Polymers 0.000 description 2
- 229910001845 yogo sapphire Inorganic materials 0.000 description 2
- HXKKHQJGJAFBHI-UHFFFAOYSA-N 1-aminopropan-2-ol Chemical compound CC(O)CN HXKKHQJGJAFBHI-UHFFFAOYSA-N 0.000 description 1
- HZAXFHJVJLSVMW-UHFFFAOYSA-N 2-Aminoethan-1-ol Chemical compound NCCO HZAXFHJVJLSVMW-UHFFFAOYSA-N 0.000 description 1
- HUHGPYXAVBJSJV-UHFFFAOYSA-N 2-[3,5-bis(2-hydroxyethyl)-1,3,5-triazinan-1-yl]ethanol Chemical compound OCCN1CN(CCO)CN(CCO)C1 HUHGPYXAVBJSJV-UHFFFAOYSA-N 0.000 description 1
- FHVDTGUDJYJELY-UHFFFAOYSA-N 6-{[2-carboxy-4,5-dihydroxy-6-(phosphanyloxy)oxan-3-yl]oxy}-4,5-dihydroxy-3-phosphanyloxane-2-carboxylic acid Chemical compound O1C(C(O)=O)C(P)C(O)C(O)C1OC1C(C(O)=O)OC(OP)C(O)C1O FHVDTGUDJYJELY-UHFFFAOYSA-N 0.000 description 1
- 229910000975 Carbon steel Inorganic materials 0.000 description 1
- 229920002134 Carboxymethyl cellulose Polymers 0.000 description 1
- AFCARXCZXQIEQB-UHFFFAOYSA-N N-[3-oxo-3-(2,4,6,7-tetrahydrotriazolo[4,5-c]pyridin-5-yl)propyl]-2-[[3-(trifluoromethoxy)phenyl]methylamino]pyrimidine-5-carboxamide Chemical compound O=C(CCNC(=O)C=1C=NC(=NC=1)NCC1=CC(=CC=C1)OC(F)(F)F)N1CC2=C(CC1)NN=N2 AFCARXCZXQIEQB-UHFFFAOYSA-N 0.000 description 1
- BPQQTUXANYXVAA-UHFFFAOYSA-N Orthosilicate Chemical compound [O-][Si]([O-])([O-])[O-] BPQQTUXANYXVAA-UHFFFAOYSA-N 0.000 description 1
- GSEJCLTVZPLZKY-UHFFFAOYSA-N Triethanolamine Chemical compound OCCN(CCO)CCO GSEJCLTVZPLZKY-UHFFFAOYSA-N 0.000 description 1
- 229940072056 alginate Drugs 0.000 description 1
- 229920000615 alginic acid Polymers 0.000 description 1
- 235000010443 alginic acid Nutrition 0.000 description 1
- 150000001412 amines Chemical class 0.000 description 1
- 229910021383 artificial graphite Inorganic materials 0.000 description 1
- DMSMPAJRVJJAGA-UHFFFAOYSA-N benzo[d]isothiazol-3-one Chemical compound C1=CC=C2C(=O)NSC2=C1 DMSMPAJRVJJAGA-UHFFFAOYSA-N 0.000 description 1
- KGBXLFKZBHKPEV-UHFFFAOYSA-N boric acid Chemical compound OB(O)O KGBXLFKZBHKPEV-UHFFFAOYSA-N 0.000 description 1
- 239000004327 boric acid Substances 0.000 description 1
- 239000010962 carbon steel Substances 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 239000010779 crude oil Substances 0.000 description 1
- 125000004122 cyclic group Chemical group 0.000 description 1
- 230000006378 damage Effects 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000002950 deficient Effects 0.000 description 1
- ZBCBWPMODOFKDW-UHFFFAOYSA-N diethanolamine Chemical compound OCCNCCO ZBCBWPMODOFKDW-UHFFFAOYSA-N 0.000 description 1
- 229940043237 diethanolamine Drugs 0.000 description 1
- YGANSGVIUGARFR-UHFFFAOYSA-N dipotassium dioxosilane oxo(oxoalumanyloxy)alumane oxygen(2-) Chemical compound [O--].[K+].[K+].O=[Si]=O.O=[Al]O[Al]=O YGANSGVIUGARFR-UHFFFAOYSA-N 0.000 description 1
- 239000005038 ethylene vinyl acetate Substances 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 239000012467 final product Substances 0.000 description 1
- 238000005187 foaming Methods 0.000 description 1
- 150000004676 glycans Chemical class 0.000 description 1
- 238000005098 hot rolling Methods 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 230000014759 maintenance of location Effects 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000005555 metalworking Methods 0.000 description 1
- 229920000609 methyl cellulose Polymers 0.000 description 1
- 239000001923 methylcellulose Substances 0.000 description 1
- 235000010981 methylcellulose Nutrition 0.000 description 1
- 230000009525 mild injury Effects 0.000 description 1
- 229910052627 muscovite Inorganic materials 0.000 description 1
- 229910021382 natural graphite Inorganic materials 0.000 description 1
- 239000003129 oil well Substances 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 238000005498 polishing Methods 0.000 description 1
- 229920001200 poly(ethylene-vinyl acetate) Polymers 0.000 description 1
- 229920001282 polysaccharide Polymers 0.000 description 1
- 239000005017 polysaccharide Substances 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 238000004513 sizing Methods 0.000 description 1
- TVXXNOYZHKPKGW-UHFFFAOYSA-N sodium molybdate (anhydrous) Chemical compound [Na+].[Na+].[O-][Mo]([O-])(=O)=O TVXXNOYZHKPKGW-UHFFFAOYSA-N 0.000 description 1
- XNRNJIIJLOFJEK-UHFFFAOYSA-N sodium;1-oxidopyridine-2-thione Chemical compound [Na+].[O-]N1C=CC=CC1=S XNRNJIIJLOFJEK-UHFFFAOYSA-N 0.000 description 1
- 230000000153 supplemental effect Effects 0.000 description 1
- 229960004418 trolamine Drugs 0.000 description 1
- 239000008207 working material Substances 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B25/00—Mandrels for metal tube rolling mills, e.g. mandrels of the types used in the methods covered by group B21B17/00; Accessories or auxiliary means therefor ; Construction of, or alloys for, mandrels or plugs
- B21B25/04—Cooling or lubricating mandrels during operation
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B17/00—Tube-rolling by rollers of which the axes are arranged essentially perpendicular to the axis of the work, e.g. "axial" tube-rolling
- B21B17/02—Tube-rolling by rollers of which the axes are arranged essentially perpendicular to the axis of the work, e.g. "axial" tube-rolling with mandrel, i.e. the mandrel rod contacts the rolled tube over the rod length
- B21B17/04—Tube-rolling by rollers of which the axes are arranged essentially perpendicular to the axis of the work, e.g. "axial" tube-rolling with mandrel, i.e. the mandrel rod contacts the rolled tube over the rod length in a continuous process
Definitions
- the present invention relates to a method of manufacturing seamless pipes or tubes (hereinafter, refer to "pipes” as “pipes or tubes”.) according to Mannesmann mandrel-mill process. Specifically, the present invention relates to a method of manufacturing seamless pipes which enables to effectively inhibit seizing between a hollow-shell and a mandrel bar as a tool for forming inner surface of pipes and to effectively inhibit occurrence of flaws on inner surface of the pipes when a hollow shell of which material is high-alloy steel such as stainless-steel or 13 Cr steel is in elongation-rolling process.
- Seamless pipes are used in many industrial fields such as energy, automobile, chemistry, industrial machinery, and construction. Seamless pipes are heavily used especially for oil well tubular and for transporting crude oil and gas. Thus, such pipes play an important role in the field related to the world's energy-resources development.
- the manufacturing method of seamless pipes in accordance with the Mannesmann mandrel-mill process is, for example, carried out based on the process shown in FIG. 3 .
- F a billet 1 as a row material of a seamless pipe is inser a rotary-hearth type heating furnace 2 and heated.
- the billet 1 heated in the rotary-hearth type heating furnace 2 is taken out from the furnace, after that, it is pierced and elongated by piercer (piercing-rolling apparatus) 3 to become a hollow shell 4.
- piercer piercing-rolling apparatus
- a mandrel bar 5a is inserted into a through hole of the hollow shell 4, and the hollow shell 4 is elongated and rolled to become an element pipe 4a. Later, the mandrel bar 5a is withdrawn from the element pipe 4a.
- the mandrel bar 5a is normally inserted into a hollow shell 4 of a temperature of 1100 ⁇ 1200°C and is exposed in a state that the bar 5a tends to seize. Therefore, lubricants are coated onto the outer surface of the mandrel bar 5a.
- the lubricants can work as a protecting coating which inhibits seizing between the mandrel bar 5a and the hollow shell 4.
- lubricants coated onto the surface of the mandrel bar 5a used are lubricants for hot-rolling which are excellent in lubrication performance in hot condition.
- an aqueous graphite-type lubricant mainly contains graphite is heavily used.
- This lubricant is usually supplied from a storage tank to production lines.
- the lubricant is showery injected onto the surface of the mandrel bar 5a to go through inside of the hollow shell 4 from a ring-shaped nozzle disposed at a position just before the mandrel bar 5a being inserted into the hollow shell 4. In this way, empirically-determined certain amount of lubricants is applied onto the surface of the mandrel bar 5a.
- Shape of outer diameter and wall thickness of the element pipe elongated and rolled by a mandrel-mill are influenced by number of revolution of each stand and shape of rolls' holes. They are also influenced by changes of friction coefficient between a mandrel bar 5a and a hollow shell 4.
- a lubricant to be coated to the mandrel bar 5a by using the lubricant which is capable to reduce friction coefficient between the mandrel bar 5a and the hollow shell 4, the hollow shell 4 is uniformly deformed in the circumferential direction and in the longitudinal direction during the elongation-rolling. Therefore it is possible to obtain element pipes having stable shape of outer diameter and stable local variations in the wall thickness.
- the mandrel bar 5a is withdrawn from an element pipe 4a with use of bar stripper.
- the element pipe 4a (hollow shell 4) and the mandrel bar 5a would seize each other, thereby flaws occur on the inner surface of the element pipe 4a. Or, the seizing prevents the mandrel bar 5a from its withdrawal.
- oxidized scale is produced on the surface of both tool and the inner surface of the material to be processed.
- An iron oxide coating consists of this oxidized scale, particularly a coating consists of dense and relatively low hardness of material including FeO and Fe 3 O 4 gives a favorable influence for lubricity during the pipe manufacturing.
- a stainless-steel such as SUS 304 series, SUS 316 series, SUS 347 series, SUS 410 series, and SUS 430 series, or an alloy steel such as STBA 25 and STBA 26, respectively defined in the Japanese Industrial Standard (JIS), does not easily produce such oxidized scale.
- the tool corresponding to the above steel needs to be made of heat-resistant low alloy such as Co-Mo series alloy and Cr-Mo-V series alloy, e. g. JIS-SKD 61.
- the tool made of these materials does not easily give oxidized scale.
- rolling load and friction coefficient during the process becomes higher, the mandrel bar 5a and the hollow shell 4 tend to seize each other.
- These factors often produce flaws on the inner surface of the element pipe. Highly accurate surface texture is required for pipe production of stainless steel or alloy steel. When such surface flaws are produced, even though they are mild damages, the obtained pipe itself cannot be shipped as a final product.
- a mandrel bar is inserted into a hollow shell of a temperature of 1100 ⁇ 1200°C, and the hollow shell having the mandrel bar therein is treated by elongation-rolling process. So, temperature of the mandrel bar right after elongation-rolling is high in the range of 100 ⁇ 400°C. Such a mandrel bar is cooled and lubricants are coated thereon again before the use for elongation-rolling with the following hollow shell.
- Patent document 1 discloses an art which inhibits seizing between a hollow shell and a mandrel bar by the following method: chemically reacting two-liquid containing the first liquid containing graphite powder and aqueous resin having reaction-curing property and the second liquid containing boric acid and so on; then, putting the hardened lubricant coating to intervene between the hollow shell and the mandrel bar.
- Patent document 2 discloses a one-component type lubricant of the first liquid of the above Patent document 1 of which aqueous resin is altered by a copolymer and further including mica.
- Patent document 3 discloses an art which inhibits seizing by applying a particular lubricant for more than once to secure the predetermined thickness of lubricant coating.
- Patent Document 1 Japanese Patent Application Laid-Open (JP-A) No. 63-230797
- Patent Document 2 JP-A No. 8-165489
- Patent Document 3 JP-A No. 2004-34072
- a mandrel bar withdrawn from an element pipe is reused (the so-called "cyclic usage") for the elongation-rolling of the following hollow shell after being transported to the bar-cooling zone to be cooled down to the certain temperature.
- practically adoptable cooling methods in the field are air-cooling and water-cooling. If sufficient space cannot be secured for putting many mandrel bars for air-cooling, water-cooling is adopted because of a short period of cooling time. In such a case, the mandrel bar is provided for the elongation-rolling of the following hollow shell soon after the water-cooling.
- a mandrel bar is water-cooled, presumably, in general, there may be two timings of lubricants coating onto the surface of the bar, that is: right after the finish of elongation-rolling of the previous hollow shell (pre-water-cooling); and a period between after complete evaporation of water on the surface of a water-cooled bar and right before the elongation-rolling of the following hollow shell.
- a lubricant is coated right after the elongation-rolling, as the mandrel bar to be coated by the lubricant is a high temperature of 100 ⁇ 400°C and water-cooled as the following step, such lubricants are required to have heat resistance and water resistance as well as seizure resistance.
- the lubricant disclosed in Patent document 1 is not designed to have water resistance and heat resistance, thereby it is necessary to apply lubricants after water-cooling and before elongation-rolling.
- Patent document 2 While, the lubricant disclosed in Patent document 2 is designed to be used basically at room temperature and water resistance is not concerned; it is necessary to use it after water-cooling. However, it is not concerned about quick-drying property, thus the lubricant has a similar problem to the one disclosed in Patent document 1.
- Patent document 3 disclosing an art, there is no description about heat resistance and water resistance required to the lubricant to be applied before water-cooling and about quick-drying property after water-cooling. So, there is no suggestion how such a lubricant should be used in detail when the mandrel bar is water-cooled.
- an object of the present invention is to provide a method of manufacturing seamless pipes in case of having a manufacturing process including water-cooling of mandrel bars, wherein sufficient productivity is maintained, and it is possible to effectively inhibit occurrence of flaws on the surface of the pipes even when the materials to be worked are stainless-steel or high-alloy steel, by forming a lubricant coating having excellent seizure resistance on the surface of the mandrel bars.
- the first aspect of the invention is a method of manufacturing seamless pipes comprising the steps of: the first coating step for forming a water-resistant coating by applying a first liquid onto a surface of a mandrel bar right after the previous elongation-rolling process; the water-cooling step for water-cooling the mandrel bar treated by the first coating step; the second coating step for applying a second liquid containing an inorganic lubricant which is excellent in high-temperature fluidity onto the surface of the mandrel bar treated by the water-cooling step, then making the second liquid permeate into the water-resistant coating to give it high-temperature adhesion, and an elongation-rolling step for elongation-rolling of a hollow shell, the elongation-rolling of said hollow shell being started within 10 seconds after the second coating step by using the mandrel bar.
- a (hot) mandrel bar right after the previous elongation-rolling process means a mandrel bar inserted into a hollow shell of a temperature of 1100 ⁇ 1200°C and withdrawn from the newly-made element pipe (originally hollow shell) after elongation-rolling.
- the temperature of the bar is usually 100 ⁇ 400°C.
- water resistance means that normally even if a lubricant on the surface of the mandrel bar is water-sprayed, more than half (50 mass %) of the lubricant can be remained without being washed away. The evaluation method in detail will be described later.
- high-temperature adhesion means that a lubricant coating adhered on the surface of the mandrel bar cannot easily come off by the contact of a hollow shell, even though the bar is inserted into the hollow shell of a temperature of 1100 ⁇ 1200°C.
- the evaluation in detail is made based on whether or not seizing between a mandrel bar and the inner surface of a hollow shell occurs.
- the second aspect of the invention is a method of manufacturing seamless pipes according to the first aspect of the invention, wherein the first liquid is an aqueous solution or an aqueous dispersion containing 20 ⁇ 40 mass % of a solid lubricant and 10 ⁇ 30 mass % of a water dispersible resin, and the second liquid is an aqueous solution or an aqueous dispersion containing 5 ⁇ 30 mass % of one or more selected from a group consisting of amine borate, potassium borate, potassium (or sodium) molybdate, and potassium (or sodium) carbonate, together with 0 ⁇ 30 mass % of a solid lubricant.
- the third aspect of the invention is a method of manufacturing seamless pipes according to the second aspect of the invention, wherein the solid lubricant is graphite, mica, or a mixture thereof.
- the fourth aspect of the invention is a method of manufacturing seamless pipes according to any one of the first to the third aspects of the invention, wherein the first coating step is carried out with a mandrel bar of 100 ⁇ 400°C, and the second coating step is carried out with a mandrel bar of 60 ⁇ 150°C.
- the fifth aspect of the invention is a method of manufacturing seamless pipes according to according to any one of the first to the fourth aspects of the invention, wherein material of the hollow shell is an alloy steel containing 5 mass % or more of Cr or a stainless steel.
- the present invention is capable to provide a method for manufacturing seamless pipes in case of having a manufacturing process including water-cooling of mandrel bars, wherein sufficient productivity is maintained, and it is possible to effectively inhibit occurrence of flaws on the surface of the pipes even when the materials to be machined are stainless steel or high-alloy steel, by forming a lubricant coating having excellent seizure resistance on the surface of the mandrel bars.
- FIG. 1 (A) is a schematic view showing an operation cycle of a mandrel bar in the method for manufacturing seamless pipes of the first embodiment of the present invention.
- FIG. 1 (B) is a schematic view showing a conventional operation cycle of a mandrel bar.
- a mandrel bar provided for elongation-rolling of a pipe in a mandrel mill is withdrawn from an element pipe, the first liquid is coated onto the mandrel bar at a temperature of 100 ⁇ 400°C (so-called "return lubrication").
- the coated mandrel bar is cooled down to 60 ⁇ 150°C by water shower, then the second liquid is coated on the surface of the cooled mandrel bar (so-called “inserter lubrication”).
- the mandrel bar coated by the second liquid is again provided for elongation-rolling of a pipe in a mandrel mill.
- the period of time is within 10 seconds from coating of the second liquid to beginning of the next elongation-rolling.
- the lubrication booth as shown in FIG. 1 (B) is not necessary, and it is capable to begin the following elongation-rolling right after inserter lubrication; thereby it is possible to enhance the manufacturing efficiency.
- first liquid and the second liquid for the use of a method for manufacturing seamless pipes of the present embodiment will be explained as below.
- the base substance to be used is a solid lubricant including graphite, mica, or a mixture thereof.
- the upper limit of the content of the solid lubricant to the total amount of lubricant is 40 mass %, preferably 35 mass %.
- spray coating becomes difficult.
- excessive solid lubricant makes supply of the lubricant from a storage tank to production lines difficult. In the end, showery injection from a nozzle to the surface of a mandrel bar becomes impossible.
- the lower limit of the content of the solid lubricant to the total amount of lubricant is 20 mass %, preferably 25 mass %. When the content of the solid lubricant is too small, seizure resistance becomes lower. There is a fear of having flaws on the pipes when elongated and rolled ones are hollow shells made particularly of stainless steel and high-alloy steel.
- Graphite may be either natural graphite or synthetic graphite.
- the purity of graphite is preferably 81% or more, and the average particle diameter is preferably 40 ⁇ m or less. If the purity of graphite is less than 81%, the lubricity may be blocked by impurity mainly including inorganic substance such as alumina (Al 2 O 3 ) and silica (SiO 2 ) as misplaced materials. Also, if the average particle diameter is 40 ⁇ m or more, such graphite is not properly dispersed in the first liquid. Therefore, the graphite cannot be supplied to the surface of a mandrel bar and of a hollow shell when used, and it cannot be stably stored under a condition of dispersion.
- Mica may be either natural mica or synthetic mica.
- natural mica the examples include sericite, muscovite, and phlogopite.
- synthetic mica include tetrasilicic potassium mica, tetrasilicic sodium mica, and fluor-phlogopite mica.
- Mica shall be included in order to improve lubricity of the lubricant under a high temperature around 1000°C. Similar to the effect of graphite, mica enhances the lubrication effect between a mandrel bar and a hollow shell. Graphite lowers friction coefficient; while, mica intervenes between a mandrel bar and a hollow shell and inhibits their fusion-bonding each other.
- mica gives a function to inhibit occurrence of flaws on the inner surface of the hollow shell (element pipe).
- the average particle diameter of mica is preferably 40 ⁇ m or less, and the purity of the same is preferably 81% or more. Because, if the average particle diameter becomes over 40 ⁇ m, such particles cannot be properly dispersed, thereby smooth supply thereof to the lubrication surface becomes difficult. Also, if the purity of mica is less than 81%, the lubricity may be blocked by impurity mainly including inorganic substance such as alumina (Al 2 O 3 ) and silica (SiO 2 ) as misplaced materials.
- a water dispersible resin to be mixed in the first liquid can make the solid lubricant as a base substance stably dispersed in water.
- the first liquid can be easily supplied when used. Therefore, the resin is included so as to make the first liquid uniformly spread on the surface of a mandrel bar and a hollow shell, and to give supplemental lubricity to the first liquid.
- a water dispersible resin to be mixed in the first liquid for example, there may be a vinyl acetate copolymer, an acrylic acid ester copolymer, a methacrylic acid ester copolymer, copolymer of two or more thereof, and an ethylene-vinyl acetate copolymer.
- the average particle diameter of such water dispersible resins is preferably 40 ⁇ m or less. If the average particle diameter becomes over 40 ⁇ m, such particles cannot be properly dispersed, thereby smooth supply thereof to the lubrication surface becomes difficult.
- the upper limit of the content of the water dispersible resin to the total amount of lubricants is 30 mass %, preferably 25 mass %.
- the lower limit of the same is 10 mass %, preferably 15 mass %. If the content of the water dispersible resin is too small, the adhesiveness and water-resistance of the first liquid is not sufficient, thereby lubrication coating may be peeled.
- a water soluble polymer may be mixed in a range which water resistance is not damaged, for example 3 mass % or less.
- the water soluble polymer include methyl cellulose and carboxyl methyl cellulose, or polysaccharide such as alginate.
- Water is contained so as to uniformly apply the lubricant on the surface of the mandrel bar.
- content of water is 30 ⁇ 70 mass %, preferably 40 ⁇ 60 mass %.
- a generally marketed silicone-series defoamant such as dimethyl siloxane
- an antiseptic agent including a thiazoline series compound such as 1,2-benzoisothiazoline-3-on, a triazine series compound such as Hexahydro-1,3,5-tris (2-hydroxyethyl)-S-triazine, and a pyridine series compound such as sodium 2-pyridine thiol-1-oxide.
- the amount of the solid lubricant therein is 50 ⁇ 150g/m 2 , preferably 80 ⁇ 120g/m 2 .
- the amount of the first liquid is-excessive, coating having more than necessary thickness for seizure resistance is formed, it is economically disadvantageous. While, when the amount of the adhered first liquid is too small, sufficient seizure resistance performance cannot be obtained.
- the second liquid to be applied onto the surface of the mandrel bar after water-cooling is an aqueous solution or an aqueous dispersion containing: 5 ⁇ 30 mass % of one or more selected from a group consisting of amine borate, potassium borate, potassium molybdate or sodium molybdate, and potassium carbonate or sodium carbonate; and 0 ⁇ 30 mass % of a solid lubricant.
- Available amine borate may be any amines which can form water soluble salt, for instance, there may be monoethanol amine, monoisopropanol amine, diethanol amine, and triethanol amine.
- a solid lubricant may be added, if necessary.
- the upper limit of the content of the solid lubricant to be mixed in the second liquid it is 40 mass % to the total amount of the second liquid, preferably 30 mass %.
- the second liquid has a difficulty to permeate into the porous coating made of the first liquid. Therefore, adhesiveness of the lubrication coating cannot be sufficiently improved.
- the lubrication coating to be formed may lack the seizure resistance.
- the first liquid and the second liquid described above were coated on the surface of test pieces, then the following evaluations thereof were carried out.
- Graphite used was scaly graphite (purity: 81% or more); water dispersible resin was a mixture of a vinyl acetate series resin and a vinyl acetate-acryl series resin at a ratio of 1:1.
- the peeling conditions of the coating under the above circumstances were evaluated in accordance with the following criteria.
- Drying property and seizure resistance were evaluated by using a rolling tester 40 diagrammatically shown in FIG. 2 .
- This rolling tester 40 is to demonstrate a condition of elongation-rolling on a single stand of a mandrel mill.
- a heated test piece 43 was rolled between a roll 42 and a flat-plate type tool 41 movably disposed in the rolling direction (the right-and-left direction in FIG. 2 ) and lubricant had been coated on the surface.
- the damage situation of the flat-plate type tool 41 was observed after the rolling.
- a test piece 43 used was a 18 Cr-8 Ni stainless steel plate (SUS 304) of 20mm in width, 10mm in thickness, and 250mm in length.
- the flat-plate type tool 41 Onto the flat-plate type tool 41, five kinds of the first liquids of which compositions are shown in Table 2 (three kinds of Examples, and two kinds of Comparative examples) were spray-coated so as the coating amount to be about 35g/m 2 , and it was cooled down to 80°C by water. Later, the second liquid of eight kinds of Examples (A ⁇ H) of which compositions are shown in Table 3 and three kinds of Comparative examples (I ⁇ K) of which compositions are shown in Table 4 were spray-coated over the coating of the first liquid so as the coating amount to be about 20g/m 2 . Finally, in order to coincide with a pitch of operation cycle of the actual mandrel mill, drying property was checked by finger touch after 10 seconds from the lubricant's coating, and downward rolling by the roll 42 was carried out.
- the elongation condition was as follows.
- Example Comparative example 1 The first liquid (mass %) Example Comparative example 1 2 3 4 5 Graphite 30.0 - 15.0 45.0 15.0 Mica - 30.0 15.0 - - Water dispersible resin 25.0 25.0 25.0 25.0 25.0 Dispersant 2.0 2.0 2.0 2.0 2.0 2.0 Water 43.0 43.0 43.0 28.0 58.0
- Graphite used was scaly graphite (purity: 81% or more); water dispersible resin was a mixture of a vinyl acetate series resin and a vinyl acetate-acryl series resin at a ratio of 1:1.
- the first liquid 4 could not be tested due to the unavailability of spray-coating.
- the second liquids D and J were not favorable in drying property as these contained a lot of water. Further, the second liquids E and K were not favorable in their drying property as these contained a lot of amine borate.
- the first liquid 4 could not be tested due to the unavailability of spray-coating.
- the first liquid 5 had an insufficient seizure resistance because of the small amount of solid lubricant.
- the second liquids D and E had an insufficient seizure resistance because of the decline of drying property.
- the second liquid I was not good at permeability due to the large amount of solid lubricant, thereby the seizure resistance was insufficient.
- the second liquid K was not good at permeability due to the large amount of inorganic lubricant, thereby the seizure resistance was insufficient.
- the second liquid J had an insufficient seizure resistance because of the small amount of inorganic lubricant.
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Lubricants (AREA)
Abstract
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
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JP2005100978 | 2005-03-31 | ||
PCT/JP2006/306928 WO2006106961A1 (ja) | 2005-03-31 | 2006-03-31 | 継目無管の製造方法 |
Publications (3)
Publication Number | Publication Date |
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EP1872878A1 EP1872878A1 (en) | 2008-01-02 |
EP1872878A4 EP1872878A4 (en) | 2009-01-21 |
EP1872878B1 true EP1872878B1 (en) | 2011-12-28 |
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Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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EP06730876A Ceased EP1872878B1 (en) | 2005-03-31 | 2006-03-31 | Process for producing seamless tube |
Country Status (5)
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EP (1) | EP1872878B1 (ja) |
JP (1) | JP4705096B2 (ja) |
CN (1) | CN101208160B (ja) |
BR (1) | BRPI0609605B1 (ja) |
WO (1) | WO2006106961A1 (ja) |
Families Citing this family (9)
Publication number | Priority date | Publication date | Assignee | Title |
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JP5392134B2 (ja) | 2010-02-15 | 2014-01-22 | 新日鐵住金株式会社 | 熱間圧延工具用潤滑剤および熱間継目無管製造用マンドレルバーの表面処理方法 |
MX339831B (es) | 2010-06-08 | 2016-06-09 | Coating Man Switzerland Gmbh * | Metodo para producir tubos sin costura. |
DE102010049645A1 (de) * | 2010-06-28 | 2011-12-29 | Sms Meer Gmbh | Verfahren zum Warmwalzen metallischer Hohlkörper sowie entsprechendes Warmwalzwerk |
DE102010052084B3 (de) * | 2010-11-16 | 2012-02-16 | V&M Deutschland Gmbh | Verfahren zur wirtschaftlichen Herstellung von nahtlos warmgewalzten Rohren in Rohrkontiwalzwerken |
CN103433283A (zh) * | 2013-08-28 | 2013-12-11 | 无锡欧龙特种钢管有限公司 | 一种轧管机石墨芯棒吹水装置 |
JP6287713B2 (ja) * | 2014-09-09 | 2018-03-07 | 新日鐵住金株式会社 | 熱間製管用の潤滑組成物 |
JP6156314B2 (ja) * | 2014-10-07 | 2017-07-05 | Jfeスチール株式会社 | マンドレルバーの冷却方法および冷却設備 |
JP6881165B2 (ja) * | 2017-09-04 | 2021-06-02 | 日本製鉄株式会社 | 継目無鋼管の製造方法 |
DE102019104540B4 (de) * | 2019-02-22 | 2021-08-19 | Chemische Fabrik Budenheim Kg | Schmierstoff und dessen Verwendung für die Heißumformung von Metallen |
Family Cites Families (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB1438215A (en) * | 1974-05-08 | 1976-06-03 | Lonz Ltd | High temperature lubricant |
JPS61252293A (ja) * | 1985-04-30 | 1986-11-10 | Hoechst Gosei Kk | 金属加工用潤滑剤とその使用方法 |
JPS63230797A (ja) * | 1987-03-19 | 1988-09-27 | Sumitomo Metal Ind Ltd | 速硬化型耐熱潤滑剤 |
CH674477A5 (ja) * | 1988-03-30 | 1990-06-15 | Lonza Ag | |
CN1042951C (zh) * | 1990-11-09 | 1999-04-14 | 上海宝山钢铁总厂 | 钢的热塑性加工用耐水性润滑剂 |
CA2088527A1 (en) * | 1992-02-06 | 1993-08-07 | Timcal Ltd. | Mandrel lubricant for manufacturing seamless tubes |
JP2910592B2 (ja) * | 1994-12-13 | 1999-06-23 | 住友金属工業株式会社 | 熱間加工用潤滑剤組成物 |
TW571000B (en) * | 2001-10-19 | 2004-01-11 | Nihon Parkerizing | Methods of preparing metal wires for plastic processing |
JP4193427B2 (ja) * | 2002-07-02 | 2008-12-10 | 住友金属工業株式会社 | 継目無鋼管の製造方法および製造装置 |
-
2006
- 2006-03-31 WO PCT/JP2006/306928 patent/WO2006106961A1/ja active Application Filing
- 2006-03-31 CN CN2006800105011A patent/CN101208160B/zh not_active Expired - Fee Related
- 2006-03-31 BR BRPI0609605-0A patent/BRPI0609605B1/pt not_active IP Right Cessation
- 2006-03-31 JP JP2007511196A patent/JP4705096B2/ja not_active Expired - Fee Related
- 2006-03-31 EP EP06730876A patent/EP1872878B1/en not_active Ceased
Also Published As
Publication number | Publication date |
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BRPI0609605B1 (pt) | 2019-07-02 |
CN101208160A (zh) | 2008-06-25 |
EP1872878A4 (en) | 2009-01-21 |
CN101208160B (zh) | 2010-05-19 |
JPWO2006106961A1 (ja) | 2008-09-18 |
EP1872878A1 (en) | 2008-01-02 |
BRPI0609605A2 (pt) | 2010-04-20 |
JP4705096B2 (ja) | 2011-06-22 |
WO2006106961A1 (ja) | 2006-10-12 |
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