Abstract: An injection method for a solid retarded acid includes mixing a solid acidic substance with a natural polymer, extruding through an extruder to produce particles; putting the produced particles in a coating pan, and sprinkling zinc acetate powder; turning on the coating pan to rotate while irradiating with an infrared lamp; spraying a glycolic acid aqueous solution with a spray gun, and continuing to rotate to obtain the solid retarded acid; injecting non-reactive liquid and the solid retarded acid into the a sand mixing truck; after the mixture is uniformly mixed in the sand mixing truck, injecting the mixture into a formation by a fracturing truck; conveying the solid retarded acid to a designated location, then stopping a pump, removing pipelines, and opening the well for gushing. The method is good in drag reduction, easy for flowback, thereby reducing the construction cost and facilitating environmental protection, and has broad application.

Abstract: The present invention relates to an injection method for a solid retarded acid. The injection method comprises the following steps: (1) uniformly mixing a solid acidic substance with a natural polymer according to a mass ratio of (0.2 to 1.

Abstract: A welding wire is provided with a hollow section for accommodating flux. The flux has a composition including: Mn: 5-20%, Si: 1-15%, TiO2: 5-25%, SiO2: 0.1-10%, Mo: 0.1-5% by weight, the balance being iron. When welding low alloy high strength steel by using the welding wire, the slag on the welding bead can be easily cleaned and a smooth surface can be formed on the welding bead which makes it easier to galvanize a zinc layer over the surface of the welding bead. The welding wire provides better welding operation performance and generates less welding spatters.

Abstract: The present invention provides a flux-cored welding wire comprising a shell having a tubular cavity, which accommodates flux. The shell is made of 400 series stainless steels. The deposited metal formed after the welding using the flux-cored welding wire of the present invention has more uniform chemical compositions. Because the loss of chromium during the transition to the deposited metal is less than 0.1%, recourses is saved and welding cost is reduced. The filling ratio of the flux-cored welding wire of the present invention is 5%-25% (preferably 10%-20%). As a result, not only the stability of the compositions in the flux is increased, but also the disadvantages to the manufacture process caused by high filling ratio are avoided. The flux-cored welding wire of the present invention will not be rusty even after it is exposed to the air for a long time.

Abstract: The present invention provides a flux-cored welding wire comprising a shell having a tubular cavity, which accommodates flux. The shell is made of 400 series stainless steels. The deposited metal formed after the welding using the flux-cored welding wire of the present invention has more uniform chemical compositions. Because the loss of chromium during the transition to the deposited metal is less than 0.1%, recourses is saved and welding cost is reduced. The filling ratio of the flux-cored welding wire of the present invention is 5%-25% (preferably 10%-20%). As a result, not only the stability of the compositions in the flux is increased, but also the disadvantages to the manufacture process caused by high filling ratio are avoided. The flux-cored welding wire of the present invention will not be rusty even after it is exposed to the air for a long time.

Abstract: The present invention is a weld wire comprising a sheath encapsulating a metal core made of powdered metal, wherein a fill percentage of the metal core is no less than approximately 12%. The metal core comprises a core composition alloyed with an alloying element or an combination of elements comprising Cr, Mo, V, W, Hf and Nb or combinations thereof, wherein a total weight percentage of the alloying element or the combination of elements in the core composition does not exceed approximately 1%. In a particular embodiment, the alloying element is Mo in the amounts selected from the range of about 0 to about 0.5 percent by weight and the fill percentage of the metal core is selected from the range of about 12% to about 30%. In a particular embodiment of the invention, the total percentage of the combination of elements is selected from the range of about 0.4% to about 0.8%.

Abstract: A weld wire electrode for use as a consumable in a gas-metal arc welding process comprises two or more strips wrapped around one another and drawn to a desired wire diameter.

Abstract: A welding wire is provided with a hollow section for accommodating flux. The flux has a composition including: Mn:5-20%, Si:1-5%, TiO2:5-25%, SiO2:0.1-10%, Mo:0.1-5% by weight, the balance being iron. When welding low alloy high strength steel by using the welding wire, the slag on the welding bead can be easily cleaned and a smooth surface can be formed on the welding bead which makes it easier to galvanize a zinc layer over the surface of the welding bead. The welding wire provides better welding operation performance and generates less welding spatters.

Abstract: A weld wire electrode for use as a consumable in a gas-metal arc welding process comprises two or more strips wrapped around one another and drawn to a desired wire diameter.

Abstract: A technique for heating a workpiece during welding is provided. The technique may comprise a heating system and a welding system. The heating system may be an induction heating system. The heating system is provided to heat the workpiece to a desired temperature and maintain the workpiece at the desired temperature as a weld joint is formed. Because the workpiece temperature is elevated, the difference in temperature between the filler material in the weld joint and the workpiece is reduced. The reduction in the temperature difference between the filler material in the weld joint and the workpiece produces a lower rate of heat transfer from the filler material in the weld joint to the workpiece. The lower rate of heat transfer, in turn, produces a slower rate of temperature decrease in the weld joint.

Abstract: The present invention is a weld wire comprising a sheath encapsulating a metal core made of powdered metal, wherein a fill percentage of the metal core is no less than approximately 12%. The metal core comprises a core composition alloyed with an alloying element or an combination of elements comprising Cr, Mo, V, W, Hf and Nb or combinations thereof, wherein a total weight percentage of the alloying element or the combination of elements in the core composition does not exceed approximately 1%. In a particular embodiment, the alloying element is Mo in the amounts selected from the range of about 0 to about 0.5 percent by weight and the fill percentage of the metal core is selected from the range of about 12% to about 30%. In a particular embodiment of the invention, the total percentage of the combination of elements is selected from the range of about 0.4% to about 0.8%.

Abstract: The present invention is a weld wire comprising a sheath encapsulating a metal core made of powdered metal, wherein a fill percentage of the metal core is no less than approximately 12%. The metal core comprises a core composition alloyed with an alloying element or an combination of elements comprising Cr, Mo, V, W, Hf and Nb or combinations thereof, wherein a total weight percentage of the alloying element or the combination of elements in the core composition does not exceed approximately 1%. In a particular embodiment, the alloying element is Mo in the amounts selected from the range of about 0 to about 0.5 percent by weight and the fill percentage of the metal core is selected from the range of about 12% to about 30%. In a particular embodiment of the invention, the total percentage of the combination of elements is selected from the range of about 0.4% to about 0.8%.

Abstract: The present invention is a weld wire comprising a sheath encapsulating a metal core made of powdered metal, wherein a fill percentage of the metal core is no less than approximately 12%. The metal core comprises a core composition alloyed with an alloying element or an combination of elements comprising Cr, Mo, V, W, Hf and Nb or combinations thereof, wherein a total weight percentage of the alloying element or the combination of elements in the core composition does not exceed approximately 1%. In a particular embodiment, the alloying element is Mo in the amounts selected from the range of about 0 to about 0.5 percent by weight and the fill percentage of the metal core is selected from the range of about 12% to about 30%. In a particular embodiment of the invention, the total percentage of the combination of elements is selected from the range of about 0.4% to about 0.8%.