256results about How to "Shorten maintenance period" patented technology

The present invention performs suitable fail-safe control while suppressing excessive increase in current for charging a DC power source or in DC link voltage, when a failure has occurred in a rotating electric machine drive unit. This inverter control device selectively performs: active short circuit control (ASC) of either upper stage side active short circuit control which turns on upper stage side switching elements of arms for all plural phases or lower stage side active short circuit control which turns on lower stage side switching elements of the arms for all the plural phases; and shutdown control (SD) which turns off all switching elements. The inverter control device performs the active short circuit control (ASC) or the shutdown control (SD) in accordance with a modulation control system that has been running when a failure has occurred in the rotation speed of a rotating electric machine or in the rotating electric machine drive unit.

The invention discloses a curing agent for sludge solidification and stabilization. The curing agent contains the following ingredients by weight percentage: 20-40% of Portland cement, 10-30% of fly ash, 10-30% of lime, 10-30% of ferrous sulfate and 5-12% of inorganic salt, wherein the inorganic salt is one or a combination of more than two selected from aluminum salt, calcium salt, sodium salt and magnesium salt. The curing agent of the invention can treat raw sludge difficult for preliminary mechanical dewatering, simplify the treatment process and difficulty, shorten the construction period, lower the cost of treatment and realize good treatment effect.

The invention discloses a coke dry quenching slope air course supporting brick overhaul construction process, which comprises the following steps: a) mounting a suspended ceiling supporting device; b) removing part of refractory bricks of a pillar of the slope air course; c) mounting an piece for anchoring the root part of the pillar of the oblique air course; d) providing castable and making castable prefabricated bricks; e) constructing the castable and building the castable prefabricated bricks; and f) removing the ceiling supporting device. The coke dry quenching slope air course supporting brick overhaul construction process has the advantages of prolonging the service life of the supporting part of the slope air course, reducing overhaul construction period, reducing maintenance cost and saving production cost.

The invention provides a method for rut maintaining and paving of a municipal road. The method comprises the following steps: (1) milling an asphalt surface layer; (2) spreading a modified emulsified asphalt bonding layer; (3) paving an emulsified asphalt cold-recycling mixture lower surface layer; (4) paving a high-elasticity rubber asphalt stress absorption layer; and (5) paving a cement-asphalt pouring type composite pavement surface layer. The combined paving layer obtained through the method has an excellent anti-rutting property and can sufficiently utilize a milled waste asphalt mixture; the integral structure has the characteristics of high rutting resistance, skid resistance, abrasion resistance, long life and low carbon.

A state in which a vehicle travels while an internal combustion engine drive torque (Te) is transmitted to a driving wheel wherein, Te and a clutch torque Tc are reduced and an electric motor torque (Tm) is increased based on the fact that a shift up condition has been established (t1). Thereafter, based on the fact that Tc is zero (t2), Tc is maintained at zero, and while maintaining a state in which Tm is transmitted to the driving wheel, a shift up operation is performed (t2 - t3). Then, based on the fact that the shift up operation is complete (t3), Te and Tc are increased and Tm is reduced (T3 - T5). After the shift up condition has been established, during the time until Tc becomes zero, the load torque (Ts) of a generator rotatably driven by the power shaft of the internal combustion engine is generated. In a hybrid vehicle equipped with an AMT, the power consumption accorded to the electric motor drive when shifting up while using the assist for the electric motor torque can be reduced.

Anhydrous press-in slurry used for a blast furnace is used for repairing the blast furnace in the damping down process through pumping and belongs to the field of a refractory material in inorganic nonmetallic materials. The anhydrous press-in slurry consists of the following materials by weight: 40-60% of aggregates, 5-15% of matrixes, 25-40% of a binding agent and 1-5% of additives, wherein the aggregates can be one of high bauxite, silicon carbide and a carbon material or a composite of the high bauxite, the silicon carbide and the carbon material, and the aggregate size is less than 0.5mm; the matrixes can be one of silica micropowder and binding clay or a composite of the silica micropowder and the binding clay generally; the binding agent can be a liquid phenolic resin; and the additives can be a curing agent and the like. The mixed powder and the binding agent are pressed in a damaged part of a lining of a furnace shell by a grouting machine and then are cured to form a solid compact whole body, thereby avoiding the damage of a water press-in material used for the blast furnace to the carbon lining after production, so as to shorten the overall time, improve the efficiency and ensure the long-time and stable operation of the blast furnace.

The invention discloses a tool and method for replacing a shaft bushing at the big end of a connecting rod of a diesel engine of a million-kilowatt-class nuclear power plant. The replacing tool comprises a main connecting rod-side piston positioning and adjusting tool and an auxiliary connecting rod-side piston connecting rod component positioning tool, wherein the auxiliary connecting rod-side piston connecting rod component positioning tool is arranged between the upper surface of a balancing block of a crankshaft of the diesel engine and the lower bottom surface of an auxiliary connecting rod cylinder; and the main connecting rod-side piston positioning and adjusting tool extends into a main connecting rod cylinder, and a jacking part on the main connecting rod-side piston positioning tool is used for jacking up a piston in the main connecting rod cylinder so as to facilitate the separation of a main connecting rod from an auxiliary connecting rod. By adopting the tool and method for replacing the shaft bushing at the big end of the connecting rod of the diesel engine, the disassembly of affiliated pipelines of related cooling water, lubricating oil, fuel oil and other systems, the removal of a cylinder head component of the diesel engine, the integral lifting-out of a piston connecting rod component and other conventional replacement works are not required when the shaft bushing is replaced, and a crankshaft bearing is directly replaced from an observation hole, thereby greatly saving the working time, obviously shortening the maintenance working period on the premise of not reducing the reliability, and lowering the maintenance cost.

Provided is a power conversion device that reduces the power capacity that is required of a power buffer circuit. A converter (3) performs full-wave rectification with respect to a single-phase voltage (Vin) and outputs a rectified voltage (Vrec) between direct current power supply lines (LL, LH). An inverter (5) receives the rectified voltage (Vrec) and supplies three-phase alternating current (Iu, Iv, Iw) to an inductive load (6). A power buffer circuit (4) is connected between the direct current power supply lines (LL, LH). The power buffer circuit (4) comprises a discharge circuit (4a) and a charging circuit (4b). The discharge circuit (4a) comprises a capacitor (C4) and a switch (Sc) connected in series. The charging circuit (4b) is configured, for example, from a step-up chopper and comprises a switch (Sl), a reactor (L4), and a diode (D40). One part of a power pulse that is input into the converter (3) is transferred between the direct current power supply lines (LL, LH) by the power buffer circuit (4).

The packet reception control device includes: a load detection section for detecting a load on a processor and outputting the detection result; and a reception control section for determining whether or not the processor should receive a reception packet based on the detection result output from the load detection section and outputting the determination result. The processor receives the reception packet according to the determination result output from the reception control section.

The invention relates to a short-circuit processing method for a stator iron core of a steam turbine generator. The texture is clearly visible, clean it with a vacuum cleaner while grinding; 3) Repeatedly scrub the polished surfaces with a white cloth dipped in alcohol; 4) Carry out the generator iron loss test to determine whether the quality of the short-circuit iron core is qualified, if so, go to step 6) , otherwise go to step 5); 5) Take out the upper layer bar at the fault point, carry out iron core processing, and return to step 4); 6) Determine whether the area of ​​the stator core welding exceeds the set threshold, if so, Make a fake iron core, insert the fake iron core into the iron core pit and fix it, otherwise fill it with insulating material and shape it. Compared with the prior art, the present invention has the advantages of wide application range, safety and reliability, and high maintenance efficiency.

The invention discloses a spanning type bridge maintenance system which comprises two travelling mechanisms, two maintenance trolley frames and a maintenance platform. The two travelling mechanisms as well as the two maintenance trolley frames are arranged on the two sides of a bridge oppositely. The maintenance trolley frames travel through the travelling mechanisms. The maintenance platform is arranged between the two maintenance trolley frames in a spanning mode. Since pre-buried barrels are arranged in the bridge in advance, support suspension arms can be directly inserted into the pre-buried barrels for paving travelling sleepers when the bridge needs to be maintained, the traveling sleeps are paved on the two sides of the bridge and do not influence passing of pedestrians and vehicles. If bridge piers exist in the maintenance process, an operating platform is made to slide towards one side of a supporting device through linear sliding devices so as to recede for the bridge piers; and after the operating platform spans the bridge piers, the bridge can be maintained as long as the operating platform is made to slide reversely and restored in position, and by adoption of the spanning type bridge maintenance system, the trouble that a maintenance device needs to be dismounted when the bridge piers exist in the maintenance process is avoided.

The invention discloses a rapid repairing process for a water wall of a power station boiler. The process comprises the steps that an infrared imaging method is used to determine a leakage area of thetube panel of the water wall; the operation of the unit is stopped, and the boiler is stopped to release water, so as to lower the water wall temperature to below 100 DEG C; a hole is arranged in theleakage area of the tube panel, and an endoscope is used to precisely position an explosion leak position and a damaged position from the hole; the water wall with the explosion leak position and thedamaged position is cut and opened; if the damaged area is large, the water wall is cut, and then welding, tube replacing and repairing are carried out; one or two tube sections to be replaced are reserved; and the tube section is firstly bent and then welded and replaced, so that the welded joint of the part is located outside the water wall. According to the repairing process provided by the invention, the repairing period is shortened; the failure treatment time of the water wall is reduced; safe, long-term and stable operation of the repaired boiler is ensured; and the economic and social benefits are effectively improved.

The invention discloses a two-pass continuous drawing method for producing a cold-drawn steel pipe. The method comprises the steps of pretreatment, pickling, phosphating, lubrication, cold drawing of rod with mandrel, drawing, and heat treatment. By changing the interaction of pickling, phosphating and lubrication, the physical and chemical properties of the pierced billet are improved greatly, especially the extension and isotropy are greatly improved greatly. Finally, the time and temperature of the heat treatment are controlled to eliminate internal stress of the product. The above processes as an organic continuous production process are indispensable to ensure parameters of each part and to obtain product with good mechanical properties and certain antirust ability, thereby reducing the pass frequency of cold drawing and reducing production cost.

The invention discloses an aluminum base gelling and curing agent, which comprises calcium aluminate, sulfur aluminum cement and an early-strengthening coagulant aid, wherein the mass ratio of the above three parts is : (1-3) : (6.5-8.5) : 0.5. The invention also discloses a preparation method of the above aluminum base gelling and curing agent. According to the method, the calcium aluminate, the sulfur aluminum cement and the early-strengthening coagulant aid, in the mass ratio of the above three parts is : (1-3) : (6.5-8.5) : 0.5, are ground, sieved, mixed and stacked up in a cone shape. After that, samples are pressed flat, and peripheral samples are stacked up centrad again in a cone shape and then pressed flat. So repeatedly for several times, and then the aluminum base gelling and curing agent can be obtained. The invention also discloses a method for treating the dredged sediment by means of the above aluminum base gelling and curing agent. Waste and gravels in the mud of the dredged sediment are separated, and then the cationic-type polyacrylamide is added to thicken and dehydrate the dredged sewage. After that, the aluminum base gelling and curing agent is added and mixed with the dredged sewage, and the mixture is stirred. Meanwhile, a water reducer is added and mixed uniformly with the above mixture. After the dehydration and solidification process, the obtained product is subjected to stabilization maintenance. The aluminum base gelling and curing agent is higher in economic, social and environmental benefits.