摘要:
In a method and a device for the ultrasonic monitoring of overlapping welded joints between a first sheet and a second sheet pulses are irradiated at an angle of between 15 and 80° into the first sheet by a first rotating probe head. The rotating probe head is arranged on a mount and has a tire rotating about the axle, coupled to the ultrasound transmitter and rolling along the first sheet, parallel to the overlapping welded joint. On ultrasound investigation of the overlapping welded joint the impulses transmitted to the second sheet are received by a second receiving rotating probe head, of similar construction to the first rotating probe head.
摘要:
A method for non-destructive testing of a weld joint of a bolt welded onto a contact area on a planar sheet metal using the lift ignition method uses directed ultrasonic signals. During the welding operation a weld pool having a modified material structure is formed beneath the contact area in the sheet metal. Ultrasonic signals are transmitted into the sheet metal using a directed and obliquely transmitting ultrasonic transmitter positioned at a coupling-in point A. An ultrasonic receiver is positioned at a coupling-out point B and receives the ultrasonic signals transmitted through the sheet metal at the coupling-out point B, an acoustic path being formed between the coupling-in point A and the coupling-out point B. The acoustic path is positioned so that it passes a center of the contact area in a distance d from this center, d being smaller than the radius of an intact weld pool and bigger than the radius of a non-intact weld pool, and the intensity of the ultrasonic signals transmitted along the acoustic path from the coupling-in point A to the coupling-out point B is detected.
摘要:
When pulverising polyurethane, polyurea and/or polyurethane/polyurea materials in a roller mill with at least two rollers (2,3) rotating at different circumferential speeds, a very economical method of operation is achieved by returning the coarse fraction falling freely out of the roll slit (4) to the roll slit (4) and stripping the fine material adhering to the roller (3) with the higher circumferential speed and discharging it separately from the coarse fraction.
摘要:
The present invention relates to a process for the preparation of moldings or films based on polyisocyanate polyadducts comprising thermoplastically molding, at a temperature of at least 50.degree. C. and at a pressure of at least 5 bar, polyisocyanate polyadducts obtained by reacting in closed molds using the reaction injection molding technique aromatic polyisocyanates; compounds having a molecular weight of from 1800 to 12,000 and containing on a statistical average at least 2.5 isocyanate-reactive groups; and one or more components selected from a diamine containing two primary and/or secondary aromatically bound amino groups and and an aliphatic or cycloaliphatic polyol or polyamine; with the provisos that the quantity of isocyanate-reactive compound is at least 30% by weight based on the total quantity of the components and that at least one of the diamine, polyol, or polyamine components comprises at least 5% by weight based on the weight of the isocyanate-reactive compound.
摘要:
The present invention is directed to composite structures by thermoplastically shaping an assembly of at least two flat thermoplastically formable plastic materials placed in layers one above the other and optionally at least one upper, lower and/or intermediate layer containing a reinforcing or filler material under such conditions of temperature and pressure that shaping is accompanied by intimate union of the individual layers of the assembly, characterized in that at least one of the flat plastic materials is based on a polyisocyanate polyaddition product having a density of at least 0.8 g/cm.sup.3 which has been prepared by the reaction of(a) aromatic polyisocyanates,(b) compounds having a molecular weight of 1800 to about 12000 and containing a statistical average of at least 2.5 isocyanate-reactive groups, optionally(c) diamines in the molecular weight range of 108 to 400 containing two primary and/or secondary aromatically bound amino groups, and optionally(d) (cyclo)alkanepolyols and/or (cyclo)alkanepolyamines in the molecular weight range of 60 to 1799 optionally containing ether groups,by a single stage or multi-stage process at an isocyanate index of 60 to 140, wherein at least one of components (c) or (d) is used in a quantity such that the total quantity of components (c) and (d) is at least 5% by weight, based on the weight of component (b).
摘要翻译:本发明涉及复合结构,其通过将至少两个平坦的可塑成形塑料材料的组件热塑成形,一个层叠在另一层之上,以及任选地至少一层含有增强或填充材料的上,下和/或中间层 温度和压力的条件是成形伴随着组件的各个层的紧密结合,其特征在于,所述扁平塑料材料中的至少一种基于密度为至少0.8g / cm 3的多异氰酸酯加聚产物,其具有 通过(a)芳族多异氰酸酯的反应制备,(b)分子量为1800至约12000的化合物,并且含有至少2.5个异氰酸酯反应性基团的统计平均值,任选(c)分子量范围内的二胺 108至400,其含有两个伯和/或二次芳香结合的氨基,以及任选的(d)(环)烷撑多糖 通过在异氰酸酯指数为60至140的单级或多级方法,任选地含有醚基的分子量范围为60至1799的(环)链烷多胺和/或(环)链烷多胺,其中至少一种组分(c)或 (d)的使用量使得组分(c)和(d)的总量基于组分(b)的重量为至少5重量%。
摘要:
In apparatuses for the preparation of phthalic anhydride and/or maleic anhydride by catalytic oxidation of naphthalene or o-xylene with air, reduced pressure is generated using liquid-jet pumps, and wash liquid is removed from the exit gas washer as a pump fluid for the liquid-jet pumps and is subsequently recycled to the exit gas washer.
摘要:
Process for the recovery of phthalic anhydride in which gases as obtained in the catalytic atmospheric oxidation of o-xylene or naphthalene are treated with a hydrocarbon containing C.sub.26.sub.- paraffins, cooling, if necessary, the hydrocarbon laden with phthalic anhydride, separating the solid phthalic anhydride followed by melting and distillation thereof.
摘要:
A finned tube heat exchanger for isolating sublimates, especially phthalic anhydride, in which the finned tubes arranged in parallel alongside one another and above one another and connected by headers and tube bends permit flow through them successively in the first, then the third, then the second and then the fourth row, and that the transverse fins are arranged in rows staggered laterally in opposite directions by an amount corresponding to from half the spacing to the whole spacing between adjacent fin edges.
摘要:
The present invention relates to a semiconductor laser having at least one quantum film in which electron hole pairs can be recombined, having at least two barrier layers between which respectively one of the at least one quantum films is disposed adjacently to these, directly in a planar manner or via respectively one intermediate film, and also having a pump device, the barrier layers having or consisting of AlzGa1-zAsySb1-y, with y greater than or equal to zero and less than or equal to one and z less than or equal to one and greater than 0.4, and/or having or consisting of AlzGauInvAsySb1-y, with z+u+v=1 and z greater than 0.25, the electron hole pairs being able to be produced directly in the quantum film with the pump device.
摘要翻译:本发明涉及一种具有至少一个量子膜的半导体激光器,其中电子空穴对可以被重新组合,其中至少两个阻挡层之间,其中至少一个量子膜中的至少一个与其相邻设置,直接在平面 方式或通过分别一个中间膜,并且还具有泵装置,所述阻挡层具有或由Al z Ga 1-z As y Sb 1-y组成,y大于或等于0且小于或等于1且z小于或等于 1和大于0.4,和/或具有或由AlzGauInvAsySb1-y组成,其中z + u + v = 1和z大于0.25,电子空穴对能够直接用泵装置在量子膜中产生。
摘要:
The present invention relates to a method for producing an electromechanical, for example piezoelectric, transducer in which a first polymer layer comprising cutouts is applied to a first continuous polymer layer by means of a printing and/or coating method, a cover is applied to the first polymer layer comprising cutouts in such a way that the cutouts of the first polymer layer comprising cutouts are closed off with the formation of cavities, and the cover is connected to the first polymer layer comprising cutouts. The invention also relates to electromechanical transducers produced by the method according to the invention, and the use of said electromechanical transducers.