49results about How to "Controllable duration" patented technology

The invention relates to an operation synthesis tester for an ultrahigh voltage direct current converter valve, which comprises a 12-pulse wave converter loop, a high voltage loop and a large current loop which are connected two by two, wherein the ultrahigh voltage loop provides a reverse restore voltage and a positive voltage for a valve to be tested; the large current loop provides a large current for flowing the valve to be tested; the 12-pulse wave converter loop provides high voltage, fault overcurrent and direct current intermittent current needed by the valve to be tested. Compared with the prior art, the operation synthesis tester for the ultrahigh voltage direct current converter valve has the advantages of good equivalence, wide applicable range, good economy, high test precision and the like.

The invention relates to the technical field of manufacturing of refrigeration equipment and particularly relates to a multi-functional modular combined cold box. The multi-functional modular combinedcold box provided by the invention comprises a box body module, tail end modules and a cold source module; the box body module is connected with at least one tail end module; each tail end module isconnected with the cold source module; the box body module is used for providing a low-temperature storage space or a low-temperature operation space; each tail end module comprises a plurality of secondary functional modules and is used for providing heat exchange conditions for a low-temperature environment; the cold source module is used for providing cold source supply for each tail end module; and a control module is used for harmonizing the secondary functional modules of all tail end modules so as to provide one or a plurality of functions including temperature regulation, humidity regulation and air regulation. The cold box formed by adopting the three modules realizes standard production, is low in manufacturing cost and short in installation period, can guarantee the quality, andis also beneficial for realizing flexible switching between different functions such as quick freezing, quick precooling, cooling, cold storage of cooled materials, cold storage of frozen materials,air-regulated cold storage and low-temperature production environment.

The invention discloses a steel cantilever combined bridge deck slab widening and reconstruction structure and a construction method thereof and aims at solving the problem existing in widening of a traditional box beam. The steel cantilever combined bridge deck slab widening and reconstruction structure comprises an original box beam and widening parts symmetrically arranged on two sides of the original box beam and is characterized in that each widening part comprises a steel cantilever, a steel bottom die, a steel guardrail and cast concrete, wherein the steel cantilever is a welding steel member of a triangular open web type structure, the steel cantilever is connected with the original box beam through an anchor bolt, and the steel bottom die is fixed to the steel cantilever, is provided with the cast concrete and form effective PBL key connection. The original box beam structure is fully utilized, and second phase dead load increase of the structure is small (only about 10% of an original structure), so that the lower portion and a foundation of an original bridge can be directly utilized, and the reconstruction project amount is remarkably decreased.

The invention relates to a novel construction method for closing traffic in a short time. The novel construction method comprises the following steps that the normal road traffic is closed, the closed road serves as a temporary construction site, and enclosure structures, water sealing systems and bracket stand column piles are constructed in the temporary construction site; the soil is excavated to the bottom elevation of a structural top board on the ground of the temporary construction site, rainfall systems are reserved, a formwork is laid, the structural top board is finished, and a pouring structure is reserved; according to the roadbed requirement, the soil is refilled on the structural top board, and normal traffic is recovered through compaction layer by layer. Monitoring points are arranged outside a pit, the rainfall systems are started for rainfall, an excavator enters the underground to excavate soil from passage inlets and outlets in the two sides of the road, and informatization construction is made according to monitored data. The construction of a structural bottom board, structural side walls and structural pillar main body structures is finished. The novel construction method can ensure the completion of self engineering, achieves improvement of the road surface traffic, and can carry out comprehensive improvement by combination with the program conditions of a municipal pipeline.

The invention provides a construction method for entering a hole in a vertical shaft directly above a main line of a subway section, and belongs to the field of urban rail transit construction. The construction method for entering the hole in the vertical shaft directly above the main line of the subway section comprises the following procedures of construction of a vertical shaft locking wellheadring beam, installation of hoisting equipment, excavation of earthwork and stonework, borehole wall supporting, horsehead door treatment, temporary pilot tunnel construction, middle pilot tunnel construction and left line excavation-expansion section construction. The construction method is used for effectively restraining the impact of vertical shaft excavation on the surrounding residents, shops and unit environment and ensuring construction safety and construction period.

The invention relates to systems used for enabling LNG pipelines to cross over a dam and construction methods of the systems, wherein one of the systems used for enabling LNG pipelines to cross over the dam and suitable for a soil, stone-built or concrete dam comprises a box culvert, slopes, LNG pipelines, an electric tracer heating system, a cushion layer and a waterproof layer, wherein the box culvert is stacked at the top of the dam; the slopes are arranged at two sides of the box culvert; the LNG pipelines cross over the box culvert and pass through the dam; the electric tracer heating system is arranged between the top of the dam and a bottom plate of the box culvert; the cushion layer is arranged between the electric tracer heating system and the bottom plate of the box culvert; and the waterproof layer is arranged at the outer side of the box culvert. The other system used for enabling LNG pipelines to cross over the dam and suitable for a soil dam comprises a box culvert, LNG pipelines, an electric tracer heating system, a cushion layer and a waterproof layer, wherein the box culvert is arranged in the dam and passes through the dam; the LNG pipelines cross over the box culvert and pass through the dam; the electric tracer heating system is arranged between a soil body inside the dam and a bottom plate of the box culvert; the cushion layer is arranged between the electric tracer heating system and the bottom plate of the box culvert; and the waterproof layer is arranged at the outer side of the box culvert. The invention also provides another system used for enabling LNG pipelines to cross over the dam and suitable for a soil dam, wherein the system comprises the LNG pipelines directly cross over the inside of the dam and waterproof cushions for wrapping the outer parts of the LNG pipelines.

The invention discloses a construction device for existing pile foundation pile connection in soil. The position of an existing pile foundation and the standard height of a pile top and the height ofa pile top super-filled concrete are determined;the soil is excavated by manual hole digging, and a bricking protection wall is set up; a super-filled part of the existing pile foundation is excavated,the super-filled part is subjected to laitance breaking, a fresh and compact concrete is broken, and it is ensured that the exposure length of a main rib of the existing pile foundation meets the requirements; the end of a manual hole diggingpile adopts an enlarged head form; a steel reinforcing cage of a pile adding part is laid down and welded with the main rib of the existing pile foundation;the concrete of the pile adding part is poured and fully vibrated and compacted. The device solves the construction problem of the existing pile foundation pile connection underground. Compared with atraditional treatment method, the device can reduce the large area of earth excavation, earthwork backfilling and concrete pouring,greatly form the protection for the foundation soil, be safe and reliable, and reduce construction costs.

The invention relates to a cable tunnel structure of a power transmission line, in particular to a bolt splicing axis bendable all-prefabricated splicing open excavated cable tunnel. The cable tunnelis structurally characterized in that the cable tunnel is formed by splicing a plurality of cable prefabricated tunnel sections and comprises the standard tunnel section and the bending tunnel sections; each cable prefabricated tunnel section comprises a concentric-square-shaped tunnel body, a grounding system and a support system; each support system comprises a groove type component and suspension arm transverse supports; the groove type components are embedded and distributed in the sidewalls of the concentric-square-shaped tunnel bodies; the suspension arm transverse supports are fixedly connected with the corresponding groove type components through bolts; each grounding system comprises an outer grounding steel ring, an inner grounding ring and connecting parts connecting the outer grounding steel ring with the inner grounding ring; the inner grounding rings are connected with the groove type components embedded in the support systems; each concentric-square-shaped tunnel body comprises a cable erection space composed of the suspension arm transverse supports and a walking maintenance channel; every two adjacent cable prefabricated tunnel sections are connected through double-end bending bolts. The cable tunnel structure has the advantages that the workload of field construction is greatly reduced; the construction quality is improved; the cable tunnel structure is convenient and fast to use and is hardly affected by weather; the construction period is controlled easily; the operation cycle is short.

The invention discloses an easy-to-replace LNG (liquefied natural gas) storage tank shock isolation cushion and a replacement method thereof. The shock isolation cushion comprises a shock isolation cushion body, a shock isolation cushion upper padding plate and a shock isolation cushion lower padding plate; the shock isolation cushion upper padding plate is arranged on the upper portion of the shock isolation cushion body, and the shock isolation cushion lower padding plate is arranged on the lower portion of the shock isolation cushion body; the shock isolation cushion upper padding plate is connected with an upper flange through upper fastening bolts, and the shock isolation cushion lower padding plate is connected with a lower flange through lower fastening bolts; the upper fastening bolts or the lower fastening bolts are bolts capable of being unscrewed; upper flange bolts are arranged on the upper plate and used for being connected with an LNG storage tank bearing platform; lower flange bolts are arranged on the lower flange and used for being connected with an LNG storage tank pile foundation. When the LNG storage tank shock isolation cushion is replaced, the padding plates need not to be jacked by a jack, cracks are avoided, and disturbance of the structure is guaranteed to the utmost degree.

The invention discloses a voltage-dip generator used for wind power generation. The voltage-dip generator comprises a host computer, a data collecting card, an IGBT driving and protecting circuit, two IGBT bilateral switches, a booster, a voltage Hall sensor, a current Hall sensor and a wind turbine generator. Three-phase voltage signals and three-phase current signals output by the voltage-dip generator are obtained by the voltage Hall sensor and the current Hall sensor; the three-phase voltage signals and the three-phase current signals output by the voltage-dip generator are acquired by the data collecting card and transmitted to the host computer; the host computer outputs voltage-dip signals and restores instruction signals to the IGBT driving and protecting circuit through the data collecting card, and leads the two IGBT bilateral switches to conduct alternately; and the voltage output by the voltage-dip generator is switched over between a primary side and a secondary side of the booster, thereby simulating various symmetrical and unsymmetrical network voltage dip faults. The voltage-dip generator has the characteristics of simple operation, high reliability, good real-timeperformance, etc., and is suitable for performance test and research of the wind turbine generator when in network voltage faults.

The invention relates to systems used for enabling LNG pipelines to cross over a dam and construction methods of the systems, wherein one of the systems used for enabling LNG pipelines to cross over the dam and suitable for a soil, stone-built or concrete dam comprises a box culvert, slopes, LNG pipelines, an electric tracer heating system, a cushion layer and a waterproof layer, wherein the box culvert is stacked at the top of the dam; the slopes are arranged at two sides of the box culvert; the LNG pipelines cross over the box culvert and pass through the dam; the electric tracer heating system is arranged between the top of the dam and a bottom plate of the box culvert; the cushion layer is arranged between the electric tracer heating system and the bottom plate of the box culvert; and the waterproof layer is arranged at the outer side of the box culvert. The other system used for enabling LNG pipelines to cross over the dam and suitable for a soil dam comprises a box culvert, LNG pipelines, an electric tracer heating system, a cushion layer and a waterproof layer, wherein the box culvert is arranged in the dam and passes through the dam; the LNG pipelines cross over the box culvert and pass through the dam; the electric tracer heating system is arranged between a soil body inside the dam and a bottom plate of the box culvert; the cushion layer is arranged between the electric tracer heating system and the bottom plate of the box culvert; and the waterproof layer is arranged at the outer side of the box culvert. The invention also provides another system used for enabling LNG pipelines to cross over the dam and suitable for a soil dam, wherein the system comprises the LNG pipelines directly cross over the inside of the dam and waterproof cushions for wrapping the outer parts of the LNG pipelines.

The invention relates to the field of water-rich deep sand layer waterproof curtain type ultra-deep foundation pit leakage pressure precipitation construction, in particular to a stepped rapid precipitation method which is a new precipitation concept and is successfully implemented in Shenyang north station of Shenyang subway line IV. According to the method, special medium-coarse sand high-water-permeability geological waterproof curtain type foundation pit leakage pressure dewatering construction serves as the background, and the defects that conventional dewatering is large in power consumption and slow in dewatering are overcome. Firstly, the funnel surface forming time of the conventional single-row layout dewatering well is long; secondly, according to traditional precipitation, precipitation wells need to be opened at the same time through the group well effect, and power consumption is large; thirdly, precipitation construction in the construction process of foundation pit operation becomes a constraint factor of the foundation pit operation to a great extent; fourthly, the water level of the dewatering well automatically controls a water pump start-stop system, the water level outside the foundation pit is automatically controlled, and accurate dewatering is achieved. The method solves the problems that after the precipitation well is constructed, the speed is high, energy consumption is low, and the construction progress is limited by the water level effectively.

The invention discloses a unit-assembly-type framework partition wall system and a construction method thereof. The framework partition wall system comprises multiple partition wall units and an assembly structure, each partition wall unit comprises a connecting structure and two half partition wall units, each half partition wall unit comprises two cover faceplates, multiple screws, a partition wall main keel, a center-penetrating keel and fireproof and soundproof cotton, the two cover faceplates are in parallel arrangement, two ends of the partition wall main keel are fixedly connected to the inner side walls of the two cover faceplates through the screws respectively, the center-penetrating keel transversely penetrates the partition wall main keel, the fireproof and soundproof cotton is filled in a space formed between the center-penetrating keel and the two cover faceplates, each connecting structure comprises a wood block, two battens and multiple screws, and the assembly structure comprises a sky keel and a ground keel. By the unit-assembly-type framework partition wall system and the construction method thereof, construction period can be effectively shortened, cost can be lowered, environment protection is realized, and fast-paced development requirements can be met.

The invention belongs to the technical field of water conservancy construction, and relates to a construction method for reconstructing a cofferdam anti-seepage system in an immersed tube tunnel. The construction method comprises the steps that remaining sand-filled long pipe bags and a river bed after an original primary cofferdam is destroyed by rush of river are adopted as a base, and stones are thrown at two sides of the base to form an inner side riprap cofferdam body and an outer side riprap cofferdam body; the space between the inner side riprap cofferdam body and the outer outside riprap cofferdam body is filled with clay to form a first-level clay cofferdam body, the inner side riprap cofferdam body, the outer side riprap cofferdam body and the first-level clay cofferdam body form an earth-rock cofferdam, and after the construction of the earth-rock cofferdam, a second-level clay cofferdam body is constructed above the earth-rock cofferdam through filling; and plastic concrete drilling occlusion piles are constructed in the middle part of the first-level clay cofferdam body as the anti-seepage system of the earth-rock cofferdam. According to the construction method, the cofferdam can be quickly reconstructed on the basis of the remaining sand-filled long pipe bags and the river bed remaining after the original primary cofferdam is destroyed by rush of river, the stable earth-rock cofferdam and the anti-seepage system thereof are formed, and remaining civil engineering in the cofferdam is guaranteed to reach the construction condition of no-water operation.