baber/WOPTO huggingface dataset:
Patent CN-1183462-A (CN)
Inventor: ZHOU HUAISHEN
IPC: C10M139/06
Filed: 1996-11-23
Abstract: 本发明公开一种润滑油添加剂及其制备方法,它是以有机钼、螯合剂、高温抗氧剂、清净分散剂和石蜡基油为原料,在首先合成有机钼之后,再以一定的配比和一定的条件下溶合而成。本发明的配方及制备方法独特,不会沉积而阻塞油路,也不会水解,性能稳定,可广泛使用在车辆、船舶、机床等大型机械上。
Patent CN-1188152-A (CN)
Title: 黑曲霉发酵葡萄糖生产葡萄糖酸镁(锰)
Inventor: JI LIANGNIAN
IPC: C12P19/02
Filed: 1997-12-17
Abstract: 本发明是葡萄糖酸镁或葡萄糖酸锰的一种新的生产方法,即在镁化合物或锰化合物的存在条件下,采用黑曲霉IFFI2230斜面菌种,将葡萄糖发酵直接生成葡萄糖酸镁或葡萄糖酸锰;本发明方法收率较高,相对于葡萄糖、葡萄糖酸镁的收率为85～94%,葡萄糖酸锰的收率为100～109%,高于现有工艺的收率;本方法还具有工艺流程短、能耗低、成本低,污染少的特点。
Patent CN-1183517-A (CN)
Title: 流体支承装置
Inventor: LEE CHANG-WOO
IPC: F16C33/10
Filed: 1997-11-10
Abstract: 一种流体支承装置,包括安装在一对轴承座一端的一对轴套,两端分别插入两个轴套通孔内的转轴以及安装在轴承座另一端的一对止推轴承。其中,第二动压槽加工在转轴的与轴套通孔内表面相对的外圆上,而第一动压槽加工在一止推轴承和转轴的一断面之间。
Patent CN-1210911-A (CN)
Inventor: WEISS HANS-JOACHIM
IPC: D02J11/00
Filed: 1998-05-19
Abstract: 本发明涉及生产彩色纱线的设备。其中单纱11,11.1和11.2在一变形喷嘴5中变形以后重新分成卷曲的单纱11.3～11.5,并在后紧密装置8中进行紧密处理,然后,在一集合紧密装置9中共同紧密处理后成为一纱线(12)而绕制在一卷绕装置10上。所涉及的各元件可简要地概括为:纺丝甬道1,上油装置2,预紧密装置3和牵伸装置4。这里上油装置2一般涉及一加油措施,紧密装置3,8和9则各涉及一缠结装置或假捻装置。
Patent CN-1222768-A (CN)
Inventor: HISASHI MORIWA
IPC: H01L21/336
Filed: 1998-11-25
Abstract: 本发明涉及一种半导体器件,该器件包括:具有第一导电类型的半导体基片;一个栅极;在基片上形成的分别位于栅极相应两侧的具有第二导电类型的源和漏扩散层;一个具有第二导电类型的低浓度扩散层,在本发明所涉及的半导体器件中,一个具有第二导电类型的中等浓度扩散层进一步形成于上述低浓度扩散层中,以充当电场驰豫层。
Patent CN-1268888-A (CN)
Title: 不含赋形剂的颗粒
Inventor: GROENENDAAL J W
IPC: A61K9/16
Filed: 1998-08-27
Abstract: 提供了不含赋形剂、适合所有的药物剂型的颗粒。还提供了通过应用优选包括空气喷射装置的筛分装置制备所述颗粒的方法。
Patent CN-1278843-A (CN)
Title: 改善延伸率的树脂组合物
Inventor: REESE J D
IPC: C09D7/65
Filed: 1998-10-30
Abstract: 本发明涉及一种纤条体的分散体和这种分散体应用于树脂组合物中以提高由该树脂组合物制成的固化膜延伸率的用途。
Patent CR-20120025-A (CR)
Title: Antigenos de virus de sincicio respiratorio recombinantes
Inventor: BAUDOUX GUY JEAN MARIE FERNAND PIERRE
IPC: A61K39/155
Filed: 2012-01-16
Abstract: Esta descripción provee antígenos de virus de sincicio respiratorio (RSV) recombinante y métodos para hacerlos y usarlos, incluyendo composiciones inmunogénicas (v.gr., vacunas) para el tratamiento y/o prevención de infección de RSV.
Patent CR-20120250-A (CR)
Title: Estructuras de fibra que contienen un complejo de encapsulación
Inventor: JACOBSON RICHARD
IPC: A01N25/18
Filed: 2012-05-16
Abstract: Se proporciona un dispositivo que comprende una estructura tridimensional que comprende una pluralidad de fibras y partículas de polvo contenidas en y/o adheridas a dicha estructura, en donde dichas parículas de polvo comprenden uno o más compuestos volátiles en un complejo de encapsulación con un agente de encapsulación molecular, un método para liberar un compuesto volátil a partir de un complejo de encapsulación molecular usando dicho dispositivo, y un aparato o sistema para realizar dicho método.
Patent CR-20210354-A (CR)
Title: Monoclonal antibodies against the beta chain region of human trbv9
Inventor: STAROVEROV DMITRY BORISOVICH
IPC: C12P21/08
Filed: 2020-02-20
Abstract: The invention relates to a monoclonal humanized antibody or an antigen-binding fragment thereof which bind specifically to the TRBV9 family of human ¿-cell receptors. The invention also relates to a nucleic acid which codes for said antibody or for an antigen-binding fragment thereof, an expression vector, a method for producing the antibody, and the use of said antibody for treating diseases or disorders associated with said family of human T-cell receptors. The invention is directed towards producing antibodies which can be used, in particular, for treating ankylosing spondylitis (AS or Bekhterev's disease), coeliac disease and blood cancers, the pathogenesis of which involves T-cell receptors of the TRBV9 family.
Patent EC-SP034702-A (EC)
Title: Combinaciones deactivador(es) del receptor de activacion de proliferacion peroxismal (ppar) e inhibidor(es) de absorcion de esterol y tratamiento para indicaciones vasculares
Inventor: KOSOGLOU TEDDY
IPC: A61P9/00
Filed: 2003-07-24
Abstract: La presente invención proporciona composiciones, combinaciones terapéuticas y métodos que incluyen: A) por lo menos un activador del receptor de activación de proliferación peroxismal; y (B) por lo menos un inhibidor de absorción de esterol de azetidinona sustituida o de B-lactama sustituida que puede ser útil en el tratamiento de condiciones vasculares, diabetes, obesidad y reducción de los niveles plasmáticos de esteroles.
Patent EC-SP034799-A (EC)
Title: Metodo de inhibir la formacion de adherencia
Inventor: WILLETTE ROBERT N
IPC: A61P43/00
Filed: 2003-10-09
Abstract: El presente invento proporciona a nuevo método para inhibir la formación de adherencia en un mamífero, particularmente en un humano, el cual comprende administrar a un sujeto en necesidad del mismo, una cantidad efectiva de un antagonista de receptores de vitronectina
Patent EC-SP088422-A (EC)
Title: Composiciones farmacéuticas sólidas que contienen pregabalina
Inventor: SHAO ZESHI JESSE
IPC: A61K9/20
Filed: 2008-04-30
Abstract: Se describe una composición farmacéutica sólida que contiene pregabalina. La composición incluye un agente que forma una matriz y un agente de hinchamiento y es adecuada para la administración oral una vez al día. Los ejemplos de agentes que forman una matriz incluyen mezclas de poli (acetato de vinilo) y polivinilpirrolidona, y los ejemplos de agentes de hinchamiento incluyen polímeros reticulados de polivinilpirrolidona.
Patent EC-SP992963-A (EC)
Title: Formulacion de tableta comprimida
Inventor: THOMPSON KAREN C
IPC: C07D265/22
Filed: 1999-05-26
Abstract: La invención se refiere a una tableta comprimida de efavirenz la cual es una formulación cargada con un 50% de droga asi como a un proceso de manufaactura de la tableta comprimida usando un método de granulación mojada.
Patent FI-20030485-A (FI)
Inventor: SORSA TIMO
IPC: B66C13/06
Filed: 2003-04-01
Abstract: The invention relates to a method for controlling swaying and swinging of a spreader in a crane and the load attached thereto, the crane comprising: a trolley, hoist gears, hoisting ropes, on which the spreader is suspended from the trolley, auxiliary gears provided with motors and motor control equipment and auxiliary ropes, and in which method the forces of the auxiliary ropes exerted on the spreader are controlled by moving the auxiliary ropes using the auxiliary gears by means of torque instructions (T<SUB>control</SUB>) obtained on the basis of the rope forces (F<SUB>rope</SUB>) of the auxiliary ropes and the rotating speed data (n) of the auxiliary gears, and whereby the torque instruction of the motor control equipment in each auxiliary gear is formed gear-specifically as a sum of a static (T<SUB>stat</SUB>) and a dynamic (T<SUB>dyn, calc</SUB>) term.
Patent FR-1605524-A (FR)
Title: Thermostable, acid resistant cation exchanger prepn. - by precipitating Gp=IV metal oxide salts to form gel which is dried and heated
IPC: B01J39/08
Filed: 1969-12-04
Granted: 1978-11-03
Abstract: Thermostable, and resistant cation exchangers are prepd. by (i) pptg. water-soluble salts of Gp. IV metal oxides in the presence of complexing salts and/or acids (opt. cooled) with solns. of anions which can form insoluble pptes. with the salified oxides so that the retarded pptn. is converted to an insoluble gel, (ii) stabilising the gel by extraction, and (iii) drying. The dried gel may be heated with extraction of the complexants or heated at high temp. without extraction of complexants which are thus carbonised or dehydrated inside the gels and deposited in the form of more or less active carbon. A structure of large surface area and high mechanical and chemical strength is obtd. The selectivity of the cation exchanger can also be adjusted by varying the complexants to give gels.
Patent GB-1051616-A (GB)
IPC: B41M5/32
Abstract: 1,051,616. Heat sensitive materials. R. KORESKA [trading as W. KORESKA]. June 5, 1963 [Nov. 19, 1962], No.22362/63. Heading G2C. A heat-sensitive material having a layer containing a salt of dithiocarbamic acid or an N-substituted derivative of dithiocarbamic acid, the cation of said salt not forming a coloured sulphide, and containing also another salt the cation of which forms a coloured sulphide and the anion is different from that of the first salt. The material may also contain of an amine or ammonium salt of a heat sensitive acid, an acid amide, a guanidine or a free amine. Zinc benzyl dithiocarbarmate and magnesium cyclo-pentamethylene dithiocarbamate are the specified dithiocarbamates and ferric stearate and ferric myristate are the exemplified second salts.
Patent GB-1052669-A (GB)
IPC: B21D22/26
Abstract: 1,052,669. Stamping. T. W. MULLEN. Dec. 7, 1964 [Dec. 17, 1963], No. 49659/64. Heading B3Q. A sheet metal blank 39 is formed into a square-edged shell (Fig. 13, not shown) by relative movement between a die 30 mounted on a platen 24, and a draw ring 18. The draw ring is formed by four upper plates which are keyed to a support 17 by T-section keyways at 45 degrees to the support sides, so that the plates are able to slide apart to expand the size of the square aperture 18. The plates are moved apart by a similar set of lower plates 28 in a pressure ring 27 by contact of the outside edges of the lower plates with depending flanges on the upper plates, the die 30 forcing the plates 28 apart at 31. The blank 39 slips inwardly relative to the rings 18 and 27 during forming (Fig. 12, not shown) and is ironed by the rounded lower edge of the ring 18. A spring-loaded ejector 40 is provided in the upper platen. The keyways in the two rings are set at right angles to each other.
Patent GB-1053084-A (GB)
IPC: D04C3/38
Abstract: 1,053,084. Stranding and braiding machines. SCHNELLFLECHTER BERLIN VEB. March 25, 1965, No. 12668/65. Headings D1C, DID and D1T. A flyback suppressor for stranding or braiding machines has a bar 1 provided with tapered bores 3 which correspond in number to the number of strands 2 and each of which contain a ball 4, the bar being inclined, in the case of bobbin carriers rotating in a horizontal plane at an angle which ensures that in the event of a reduction in centrifugal force the balls will fall back towards the narrowest point of the bore. For bobbin carriers rotating in a vertical plane the bar has a cover plate 8 and spring 6. The bar 1 and plate 8 have threading slots.
Patent GB-1054330-A (GB)
IPC: C01B21/084
Abstract: 1,054,330. Trifluoroamine oxide. ALLIED CHEMICAL CORPORATION. Aug. 13, 1963 [Aug. 15, 1962], No. 31965/63. Heading C1A. Trifluoroamine oxide F 3 NO is made by introducing gaseous elemental fluorine and gaseous nitric oxide into a reactor and regulating the rates of feed and relative proportions of the reactants so as to maintain a spontaneous exothermic reaction. The reactor is preferably immersed in a fluid at -50 to - 130 C. and the reaction products rapidly cooled by direct discharge into a quenching chamber maintained for example at 125 to - 130 C. The reactants may be diluted with helium or argon and should be vigorously mixed, the reaction time being from 0.5 to 10 seconds. Trifluoroamine is separated from by-products, principally nitrosyl fluoride, by fractional condensation and distillation.
Patent GB-1143616-A (GB)
IPC: B41M1/12
Abstract: 1,143,616. Electrostatic printing. MONSANTO GRAPHIC SYSTEMS Inc. 29 July, 1966, No. 34274/66. Heading B6C. In electrostatic printing wherein electricallycharged powder particles are transferred from a member with apertures forming the required image to the surface to be printed by means of an electric field, the apertures are closed on the side away from the surface to be printed and are loaded with the powder prior to the transfer of the powder. The apertured member or a backing member closing the apertures, or both members, are made of conductive material. In one embodiment, Fig. 3, a rotary cylinder 30 has apertured patterned parts 34 . . . 42 separated by insulating pieces 44 and closed at their inner surfaces. Powder is supplied to the parts 34 ... 42 from a container 50 having a scraper 54 which removes excess powder from the parts 34... 42. The apertured parts pass to a printing station where material 64 to be printed passes between the cylinder and an electrode 60, and a potential is applied at 58 to the apertured part or to a backing plate closing its inner side. The resulting electric field causes the transfer of the powder image to the material 64, the image being subsequently fixed at station 72. The container 50 may include a brush for depositing the powder on the cylinder 30. In modifications, the powder is supplied to the cylinder 80, Fig. 6, from a container 87 by an electric field. A powder cloud is formed in the container by vibrating the container or by using a fluidized bed. As shown, a rotary brush 108 dips into the powder and carries it against wires 113 between which and the cylinder an electric field is set up to cause the powder to be deposited in the pattern apertures on the cylinder. At the printing station, the apertured member positioned at the station may be vibrated to ensure release of the powder. For this purpose the backing plate of the apertured member may be engaged by metal pellets on radial wires carried by a rotary shaft (Fig. 7, not shown) or by air-driven hammers (Fig. 8, not shown). According to another embodiment, Fig. 10, the pattern apertures are formed in a belt 152. At the loading station 166 and the printing station 176, 178 the belt 152 is supported by another belt 160 which closes the apertures on the inner side. Electric potentials are applied to the belt 160 and an electrode 168 to provide the electric field at the printing station. During transfer of the powder image, a vibrator 184 may operate as described above. If the material to be printed is sufficiently conductive, the electrode such as 168 may be omitted and an electric potential applied directly to the material.
Patent GB-1226545-A (GB)
IPC: B01F7/24
Filed: 1967-06-01
Abstract: 1,226,545. Mixing apparatus. DIXON MALT CO. Ltd. and ENZYMIC MALT CO. Ltd. 31 May, 1968 [1 June, 1967], No. 25457/ 67. Heading B1C. [Also in Divisions B8 and C6] Malting grain moves upwardly through an inner tube 35, Fig. 1, to fall downwardly outside it against a countercurrent of gas admitted through galleries 7 and 15. The screw 31, by which the grain is elevated, is carried on a hollow shaft 30 rotated by a variable speed motor 10 through a flexible coupling 29. The shaft also carries four paddles 42 at the top and a single paddle 34, Figs. 1 and 2, offset from the axis of rotation, at the base. The feed screw flares outwardly around a conical skirt 32 and ends in a shovel portion 33 travelling over the base plate 41. Paddle 34 displaces outwardly any grain that falls inside the radius of the shovel. With the drive reversed, the shovel will eject grain through the outlet 23 when the slide plate 47 is open. The pitch of the base portion of the screw is progressively inversely proportional to the square of the diameter of the conical skirt. A series of gas jets 22 can counteract bridging or cavitation of the grain, should this occur. Grain in the area of the bottom portion of the shaft is moved by gas or liquid from a small nozzle 45. In an alternative apparatus, the grain is elevated with high pressure gas from a nozzle 78, Fig. 4, adjustable in height, and is agitated by radially extending blades 82 or rakes with upstanding teeth. Deflectors 66 and 67 facilitate the charging of grain into the apparatus from an inlet 68 and the circulation of grain ejected from the top of tube 62. Gassifying legs 75 may be provided in each of these apparatuses.
Patent GB-1234185-A (GB)
IPC: G01F23/56
Filed: 1967-09-04
Abstract: 1,234,185. Movable magnet switches. RONALD TRIST CONTROLS Ltd. 4 Sept., 1968 [4 Sept., 1967], No. 40263/67. Heading H1N. Sealed magnetic reed contact units 9 are operated when respective yoke members 7 are bridged by a permanent magnet 3 movable in a non-magnetic tube 2. The contact units 9 are mounted between soft iron polepieces 8 on the yoke members 7 which are also made of soft iron and mounted on the tube 2. The magnet 3 is mounted on a rod 4 on a float 5 and may operate a plurality (only two shown) of contact units, each with respective yoke members 7 and soft iron tubes 11 between the units to ensure that the contacts are operated quickly and only when the members 7 are bridged.
Patent GB-1251845-A (GB)
IPC: A01K89/027
Filed: 1969-01-02
Abstract: 1,251,845. Fishing reel. CARPANO & PONS. 2 Jan., 1969 [7 Feb., 1968], No. 385/69. Heading A1A. [Also in Division F2] A fishing reel, Fig. 1 (not shown), includes a retrieval pick-up (not shown) driven by a hand crank 6 linked to drive gears 5, (7) through a clutch/brake mechanism which is disconnected on rotating the crank 6 in the paying-out direction. A boss 11 of a casing 1 rotatably mounts a sleeve 12 wherein a shaft 13 is rotatable and axially movable. A nut 14 screwed to the shaft 13 allows adjustment of the force exerted on the end of the sleeve 12 by a spring 15. The gear 5, freely rotatable on the sleeve 12, engages an axially movable friction disc 18, backed by a ratchet wheel 12d integral with the sleeve 12. A disc 20, angularly fixed relatively to, but axially movable on the sleeve 12, has protrusions 20a, 20b, Figs 3-4, cooperable with tongues 22a, 22b on a disc 22 rigid on the end of the shaft 13, further tongues 23a, 23b fitting into apertures 21a, 21b in the disc 20. On turning the crank 6 to reel in line, the tongues ride out of the apertures, Fig. 6, and so force the disc 20 against a friction ring 19 contacting the gear 5, and increase the grip of the gear 5 by the sleeve 12 through the friction disc 18. The gear 5, under the action of the spring 15, is thus constrained to rotate with the sleeve 12 and shaft 13. Thus, by rotating the crank in the latter direction the friction drive between the shaft 13 and gear 5 is enhanced, while in the opposite direction it is loosened: for casting the crank 6 is turned slightly in the paying out direction to disengage the tongues 23a, 23b, a pawl 24 cooperating with ratchet teeth 12d to allow rotation of the sleeve 12 only for reeling in. Tongues 18a on the disc 18 cooperating with teeth 5a on the rear face of the gear 5, Figs. 8-11 (not shown), provide an audible warning of paying out.
Patent GB-1257069-A (GB)
IPC: C07D487/04
Filed: 1969-11-07
Abstract: 1,257,069. Polyphenylene ethers. FARBENFABRIKEN BAYER A.G. 7 Nov., 1969 [28 Nov., 1968], No. 54583/69. Heading C3R. In Example 5, 2,6-dimethyl-phenol and dry oxygen at 23‹ C. were introduced into anhydrous benzene containing anhydrous magnesium sulphate and as catalyst anhydrous curpous chloride and a cyclic amidine of the formula where R<SP>1</SP> and R<SP>2</SP> are each methyl radicals, R<SP>3</SP> and R<SP>4</SP> are each hydrogen atoms, n is 1, stated to be novel. Oxidative coupling occurred to produce a polyarylene-ether.
Patent GB-1265880-A (GB)
IPC: C08G63/685
Filed: 1969-09-15
Abstract: 1,265,880. Coating of wires. DR. KURT HERBERTS & CO. 15 Sept., 1969 [23 July, 1969], No. 45308/69. Heading B2E. [Also in Divisions C3 and H1] A thermosetting wire-coating lacquer is prepared from a polyesteramide containing 5- membered imide rings, cresol, naphtha, xylene and polymeric butyl titanate. The lacquer is applied in 6 layers to a copper wire using roller and felt in a horizontal wire-laquering oven 3 metres long at a temperature of from 410-450C at the rate of 9 to 13 metres per minute.
Patent GB-1290219-A (GB)
IPC: C08G18/08
Filed: 1970-07-24
Abstract: 1290219 Coatings NAPHTACHIMIE 24 July 1970 [25 July 1969] 36045/70 Heading B2E [Also in Division C3] Substrates, such as leather, parquet or cement floors, cloths made of natural or synthetic fibres, cardboards and plastic foams may be coated with polyurethane prepolymer compositions prepared by subjecting a polyhydroxyl compound to a preliminary dehydration treatment and adding to it 100 to 5000 p.p.m. by weight with respect to the prepolymer of a hydrolysable halogenated compound, followed by an organicpolyisocyanate in an amount greater than that theoretically necessary for reaction with the OH groups of the polyhydroxyl compound and, after reaction has ceased, a catalyst to promote the subsequent reaction of the NCO residues of the prepolymer with compounds having labile H atoms (see Division C3). In Examples 3, leather is finished with a prepolymer composition which is cured by reaction with atmospheric moisture. The prepolymer compositions may also be used as primers for promoting the bonding of plastics or elastic substances, e.g. mastics, foams, glues, polyurethane-based paints or substances based on silicones, epoxy resins, polyesters, polyamides and polyvinyl chloride to carriers such as concrete, cement, plaster, sandstone, earthen-ware, porcelain, glass, ceramics, ferrous alloys, light alloys and plastics materials such as polyester resins. In Example 1, aluminium is primed with a prepolymer composition and a polyurethane mastic is then poured onto the primed substrate.
Patent GB-1296349-A (GB)
IPC: H03H11/12
Filed: 1970-03-19
Abstract: 1296349 Active filters; transistor amplifiers LIONMOUNT & CO Ltd 19 April 1971 [19 March 1970] 13365/70 Headings H3T and H3U An adjustable active filter comprises: an amplifier A1 with resistors R1<SP>1</SP>, R2<SP>1</SP> connected in series with its input and output respectively; a first capacitor C1 connected from the output side of the amplifier to a variable tapping on R1<SP>1</SP>; and a second capacitor C2 connected between a terminal common to the amplifier input and output and a variable tapping on R2<SP>1</SP>. A second amplifier A2 and further capacitors C K  may be included.
Patent GB-1297336-A (GB)
IPC: F23Q9/04
Filed: 1971-05-28
Abstract: 1297336 Multiple-jet burners; pilot jets S A LEBLANC 28 May 1971 [21 Dec 1970] 17840/71 Headings F4F and F4T In a gas-operated apparatus (e.g. water  heaters or boilers) mutual firing of the main  burners 2 of the apparatus is achieved by a bar 6 provided with bent and curved lugs 8 constituting conduit means 9 disposed transversely between adjacent rows of main burners at a level slightly higher than where the gas emerges from the main burners. A pilot burner 5 is situated opposite the bar 6 adjacent the central row of main burners 2.
Patent GB-1303641-A (GB)
IPC: F28F9/18
Filed: 1969-02-21
Abstract: 1303641 Welding by fusion FOSTER WHEELER JOHN BROWN BOILERS Ltd 23 Feb 1970 [21 Feb 1969] 9592/69 Heading B3R In making a seal weld between a tube 10 and a tube plate or header 14 in a heat exchanger, wherein the tube extends partly or, preferably, completely, through a plate bore, a filler insert 20 is fitted into an annular groove preparation 16 in the plate surrounding the tube and is retained in place during non-consumable electrode arc welding by which the tube, plate and insert are fused together. The insert may be a piece of filler wire e.g. of circular cross-section, bent to shape, or in sections providing the gaps therebetween are less than 3/32 inch. The insert composition is such as to avoid hot cracking or embrittlement. The insert may be retained by a shoe or roller fitted on the welding head; or, preferably, so as to centre the tube, by punching over, at 24, the edge of the preparation 16. In addition, the lower edge 26 of the preparation may be burred to assist tube centring. In the event of tube or weld failure in use, the weld may be removed by cutting, the tube removed if necessary, the plate re-prepared, a new tube inserted if necessary, and a new seal weld made. To prevent entry of contaminants into the weld, a soft metal ring (34, Fig. 4, not shown) may be tightly fitted between the tube and plate adjacent the filler insert.