A crawler track mechanism including a plurality of track plates each mounted on track chain links, the chain links being interconnected by bushes having an outer sleeve rotatably journalled on an inner sleeve which in turn is rotatably journalled on a central cylindrical pin). A drive sprocket, and if necessary an idler sprocket, includes recesses having a semi-circular cross section to receivably locate the bushes. The bushes, by virtue of the relative rotation between the pin, the inner sleeve and the outer sleeve, reduce friction and wear between the drive sprocket and the chain bushes.

Crawler track assembly

The present invention provides an electrode for hydrogen generation of which the hydrogen overvoltage is sufficiently low and which is not affected by poisoning due to iron ions, and furthermore, of which the durability is superior because during operations and stop-and-start control, the hydrogen overvoltage does not rise and exfoliation of the supported material does not occur. The present invention also provides a method for manufacturing the aforementioned hydrogen generation electrode and an electrolysis method using the electrode for hydrogen generation as a cathode. An electrode for hydrogen generation is used in which a platinum alloy including platinum and one metal selected from the group consisting of nickel, cobalt, copper, silver, and iron, or an amorphous material of a transition metal element and platinum is supported on a conductive base material. This electrode is obtained by coating a metal compound solution including one selected from the group consisting of nickel, cobalt, copper, silver, and iron, and a platinum compound solution which forms an ammine complex; drying; thermally decomposing at a temperature in a range from more than 200° C. to 700° C. or less; and then subjecting to a reduction processing.

Electrode for Hydrogen Generation, Method for Manufacturing the Same and Electrolysis Method Using the Same

The invention discloses production technology for an extra-width printing nickel screen, which comprises the following steps: I, preparing molds: (1) customizing a base mold; (2) electroplating a copper coating on the base mold; (3) rolling lattice points on the external layer of the base mold; and (4) electroplating a nickel coating on the base mold to produce a screen mold; and II, preparing the nickel screen by using the prepared molds: (1) carrying out primary nickel plating to prepare a single screen; (2) removing the screen; and (3) carrying out secondary nickel plating on the single screen The electrical nickel-plating bath adopted by the production technology comprises a plating bath body, wherein a cathode tube and a titanium basket having a plurality of baskets are arranged in the plating bath body; more than one filter pumps are arranged outside the plating bath body; a water inlet and a water outlet of the filter pump are respectively connected with the plating bath body;a carbon brake is fixedly arranged below the top of the cathode tube; the bottom of the carbon brake is connected with a power supply, and the top of the carbon brake is contacted with the cathode tube; and nickel cubes are put in the baskets of the titanium basket, and the number of the nickel cube is uniformly reduced from the middle of the titanium basket to the two sides of the titanium basket The extra-width printing nickel screen prepared by the production technology and the electrical nickel-plating bath has the advantages of good uniformity of opening, even thickness and large aperture

Production technology for extra-width printing nickel screen and electrical nickel-plating bath

The invention relates to a method for preparing a material containing sulfur and nickel. The preparation method is as follows: in an electroplating system of nickel-containing electroplate liquid, sulfur-containing compound solution is dropped near a negative plate in the electroplate liquid; the sulfur-containing compound directly reacts with the nickel ions in the electroplate liquid in one step according to the equation below; and on the negative plate, the chemical precipitation of NiS and the electrodeposition of nickel are performed simultaneously to prepare the material containing sulfur and nickel. The reaction product NiS is deposited on the negative electrode; and meanwhile, the electrodeposition of nickel is performed continuously on the negative electrode under the action of the electric field in the electroplating process, namely the chemical precipitation of NiS and the electrodeposition of nickel can be performed simultaneously so as to prepare the material containing sulfur and nickel. The invention has simple process and convenient operation; the new sulfur-containing compound is selected as sulfur source and the codeposition mode combining the chemical precipitation of sulfur with the electrodeposition of nickel is adopted to prepare the material containing sulfur and nickel, thus the sulfur content of the material containing sulfur and nickel is easy to control, and the problem that the material containing sulfur and nickel is difficult to prepare and the sulfur content is difficult to control can be solved; and the product quality is stable, the process flow is short and the large-scale production can be realized.

Method for preparing material containing sulfur and nickel

PROBLEM TO BE SOLVED: To operate with a stable electrolytic voltage over a long periods by electrolytically fluorinating while generating boiling bubbles on the surface of an anode. SOLUTION: An organic compound is electrolytically fluorinated by hydrofluorination. In such a case, the electrolytic fluorination is executed while generating boiling bubbles on the surface of the anode. The electrolytic fluorination is performed by dissolving or dispersing the organic compound in hydrogen fluoride. Concretely, hydrogen fluoride and the organic compound are charged into an electrolytic cell provided with the anode and a cathode and electric power is applied between the anode and the cathode. As the hydrogen fluoride used for the electrolytic fluorination, hydrofluoric acid anhydride on the market as it is or after removing a small quantity of water contained in the hydrogen fluoric acid anhydride, is used. As the organic compound to be an object of the fluorination, an organic compound having hydrogen atom directly bonded to carbon atom or the like is used. As a result, a perfluorinated compound is obtained at a high yield.

Electrolytic fluorination method

PURPOSE:To improve the durability of a cathode when an aqueous alkali chlo- ride soln. is electrolyzed by an ion exchange membrane method, by using a cathode having low hydrogen overvoltage and by carrying out electrolysis while keeping the concn. of iron ions in a catholyte at a prescribed value or below. CONSTITUTION:A cathode having low hydrogen overvoltage is placed in an electrolytic cell for electrolyzing an aqueous alkali chloride soln. by an ion exchange membrane method. The concn. of iron ions in a catholyte in the cell is kept at <=0.5ppm to prevent the deposition of iron on the cathode during electrolysis. Thus, the deterioration of the cathode is prevented, the durability is improved, and high efficiency is maintained for a long term.

Method for electrolyzing aqueous alkali chloride solution

PURPOSE:To reactivate a deteriorated electrode economically, certainly and simply, by a method wherein the deteriorated active electrode is dissolved by a mineral acid while attached to an electrode chamber and, after cathodic electrolysis is performed in an alkali solution, nickel plating containing sulfur is applied to the treated electrode. CONSTITUTION:A nickel plated active electrode containing sulfur deteriorated through use in hydrogen generation is dissolved by a mineral acid such as hydrochloric acid, sulfuric acid or nitric acid while attached to an electrode chamber. The dissolving speed of the nickel plating film containing sulfur is rapid in those mineral acids as compared with the base material of the electrode and said plating film can be dissolved and removed without damaging the base material of the electrode. Subsequently, the electrode is immersed in an alkali solution to perform cathodic electrolysis to certainly remove the dissolution residue on the surface of the electrode as well as to clean the electrode. In the nixt step, nickel plating containing sulfur is applied to the cleaned electrode by using a nickel plating bath containing a soluble sulfur compound to reactivate the same, certainly and simply.

Reactivation of active electrode

PURPOSE:To produce an electrode having low hydrogen overvoltge and excellent durability and corrosion resistance, by subjecting the surface of a metallic base material applied with underlying nickel plating to nickel plating by the use of a nickel bath contg. sulfur. CONSTITUTION:Underlying nickel plating is applied on the surface of a metallic base material by using a nickel plating bath contg. ammonium ions and further nickel plating is applied thereon by using a nickel plating bath contg. sulfur. The plating bath for said underlying plating contains soluble nickel salt such as nickel chloride and ammonium salt, and the concn. of the ammonium ions therein is required to be >=0.05mol concn. The plating bath contg. sulfur contains soluble nickel salt, and soluble sulfur-contg. compds. such as salts of oxo acids having <=5 oxidation number of sulfur like thiourea, thiocyanate, sulfite or the like. It is possible to obtain underlying nickel plating of good adhesion by applying copper plating or electroless nickel plating beforehand on the metallic base material.

Yoshida Setsuo

Papers

Method for electrolyzing aqueous alkali chloride solution

Reactivation of active electrode

Production of electrode