31results about How to "Reduce internal temperature rise" patented technology

The invention discloses a retarded cement grinding aid and a preparation method thereof. The retarded cement grinding aid comprises 0.01-0.02wt% of sodium carboxymethyl cellulose, 25-30wt% of molasses calcium, 5-10wt% of citric acid and the balance of water, wherein the total percent is 100%. The retarded cement grinding aid provided by the invention has the beneficial effects that the molasses calcium is used instead of the molasses and cane sugar commonly used at present, is a powdery product prepared by neutralizing the molasses with lime, has better water reducing and retarding effects than the molasses and saves the cost; and the hydration and hardening time of the cement is effectively lengthened so that the freshly mixed cement concrete can maintain the plasticity in a longer time, thus adjusting the setting time of the freshly mixed cement concrete.

The invention discloses a cooling device, a stator and a wind driven generator. The cooling device comprises an air cooling system and a liquid cooling pipeline; the air cooling system comprises a gaseous medium flowing path enabling a gaseous medium to circulate in the wind driven generator and a first heat exchange device arranged on the gaseous medium flowing path; the liquid cooling pipeline comprises a first part located in the first heat exchange device and a second part located in the stator or on the outer surface of the stator; and cooling liquid in the liquid cooling pipeline flows through the first part and the second part in sequence. With the air cooling system and the liquid cooling pipeline combined, the cooling efficiency of the wind driven generator is improved, the internal temperature rise and temperature gradient of the wind driven generator are reduced, and the cooling device has the advantages of high reliability, easiness in maintenance and low cost.

The invention discloses an energy saving type control method of composite switch and an energy saving type composite switch. A first terminal of the composite switch is used for connecting with an electric network, a second terminal is used for connecting with an electric power capacitor, a third terminal is used for connecting with one pole of a relay direct-current power source, a fourth terminal is connected with another pole of the relay direct-current power source after being connected with a control switch in series; a bidirectional controllable silicon switch and a relay normally open contact are arranged in parallel between the first terminal and the second terminal; the third terminal and the fourth terminal are respectively internally connected with A,B ends of a relay coil; a fifth terminal is directly connected with the same pole of the direct-current power source connected with the fourth terminal; a capacitor is connected between the fifth terminal and the A end of the coil; a resistor is connected between the A end of the coil and the third terminal. Because the current across the relay coil is greatly reduced after applying the electric power capacitance, the heating amount of the coil is obviously reduced and furthermore the whole work reliability of the relay and the composite switch is greatly increased.

The invention discloses a preparation method of high-volume stable stability concrete, and the high-volume stability concrete is mainly applied to a high-temperature and dry environment. The high-volume stable concrete comprises the following components in a mix proportion: 900-1200 kg / m<3> of rubbles, 500-800 kg / m<3> of river sand and 300-500 kg / m<3> of binding material, wherein the mixing amount of an efficient water reducing agent is 0.3-1.2%; the water-binder ratio value is 0.2-0.5; the rubbles are obtained by mixing rubbles in three granularity ranges in proportions; the river sand consists of river sand in two granularity ranges; the binding material is composed of Portland cement, superfine slag powder and coal ash. The concrete provided by the invention has a higher aggregate stacking density (65-75%), so that the using amount of the binding material is reduced, the proportions of admixtures such as slag and coal ash are higher, the segregation resistance, bleeding capacity and early-stage volume stability (particularly plastic shrinkage crack resistance) of the concrete are obviously improved, and the later volume deformation (self-constriction and drying shrinkage) of the concrete is smaller; the preparation method is particularly suitable for preparing C30-C50 grade concrete applied in high-temperature and dry regions.

The invention discloses a metalized polypropylene film capacitor for an induction cooker. The metalized polypropylene film capacitor comprises an upper insulating cover, a lower insulating cover, a capacitor core, metal spraying layers, conducting posts and lead-out terminals, wherein the upper insulating cover is fixedly connected with the lower insulating cover through an explosion-proof board; an impregnant is arranged in a gap between the lower insulating cover and the explosion-proof board; a buffer layer is arranged on the inner surface of the lower insulating cover; an explosion-proof layer is arranged on the inner surface of the buffer layer; the capacitor core is formed by winding two superimposed metalized film layers; each metalized film layer comprises a polypropylene film; a metal aluminum layer is evaporated on each polypropylene film as an active region of an electrode in a high vacuum environment; a pure-zinc thickened region layer is evaporated on the edge of each active region in a thickened manner; wavy edges are arranged at the outer sides of each polypropylene film, the corresponding active region and the corresponding thickened region; the metal spraying layers are arranged at two ends of the capacitor core; and lead-out terminals are arranged on the upper insulating cover. The metalized polypropylene film capacitor is stable in performance, good in temperature tolerance, long in storage time, high in antioxidant capacity and small in high-frequency loss.