Hopper with inclined electrodes for electric heating of concrete mix

FIELD: construction.

SUBSTANCE: invention relates to the field of construction, namely, to structures for electric heating of a concrete mix in construction conditions. The electric heating hopper of cyclic action is made as installed with the angle of inclination 70…75° to the bottom by steel plate electrodes having horizontal strip cuts with height of 8…10 mm, arranged along the height of the electrode via 5…6 cm.

EFFECT: invention will make it possible to provide for increased evenness of heating of a concrete mix, to reduce duration of heating of a concrete mix, to reduce power consumption.

1 dwg

 

Known electroresistive bunker cyclical steps to electroresistive concrete mixture, equipped with a vertically mounted electrodes [1].

The closest in technical essence is electroresistive bunker cyclical actions with vertically fixed electrodes that have a horizontal stripe cutouts height of 50 mm [2].

However, the disadvantage electroradiographic hopper is the increase in the duration of heating of the concrete mix and energy consumption. The cut height of 50 mm, made in the electrodes and employees capacitors steam-air mixture, reduce the electric field strength in the zone of the cut and in front of them, causing a significant variation of the temperature of the heated volume.

The basis of the claimed invention is the task of improving the quality (uniformity) heating the concrete mix and the reduction of energy consumption.

The problem is solved in that in the construction electroradiographic hopper cyclical action 1 (see figure 1) installed steel plate electrodes 2 with the angle of 70-75° (inclined) to the bottom and made a horizontal strip cut 3 height 8...10 mm, located at the height of the electrode through 5...6, Electrodes attached to the tank with electrical insulation 4. D what I provide quality heating concrete mix, adjacent to the side walls of the hopper, as in existing installations with vertically spaced electrodes, they are made with the requirement of maintaining the same distance to the outer electrodes. This requirement is ensured by the implementation of the side walls of the hopper with the same angle (70-75°)as the electrodes. For uniform distribution of the concrete mixture between the electrodes as the analogue to the tank attached to the vibrator 5. Discharging the heated concrete mix from the hopper through the shutter outlet openings 6.

As is known, the main reason for the decline in the quality of heat is the presence of electrodes, oxide films, particles of hardened concrete and cement mortar with air inclusions, causing an increase of the contact resistance at the transition from the electronic conductivity of the electrode for lithium concrete mix. Contact resistance occurring at the electrode surface, contributes to the overheating of the electrodes and the appearance of vapor bubbles on the electrode surface. Bubbles under the influence of the pressure of their own masses flock to the free surface. In the bubble mode of motion is transformed into a shell, in which the vapor is transported in the form of tubes, bounded on one side surface of the vertically installed the aqueous electrode, as with other concrete mixture. Vapor bubbles, having a large electric resistance, shield the surface of the electrode, preventing sufficient electric contact of the latter with a concrete mixture and to increase the current density on the electrode area. The formation of vapor bubbles, rising temperatures and increasing current density on the electrode area of the vertical electrode complement each other, and each of these processes contributes to the development of another. In this regard, the process of raising the temperature on the contact surface of the vertical electrode, and the amount of heat the mixture becomes difficult to manage and concrete mixture is heated unevenly.

When installing electrodes in electroresistive hopper angle (70...75°)to the surface of its bottom vapor bubbles formed on the surface of the electrode above the surface of the electrode), under the influence of buoyancy force upward. The bubbles get into the subcooled areas of the concrete mix and condense them, transferring its heat, thereby equalizing the temperature across the thickness of the heat. When determining the angle of inclination of the electrodes 70...75° to the surface of the bottom taken into account the following circumstances:

- creation of conditions under which vapor bubbles (which appeared on the surface of the electrodes), per mediumint up covered the largest volume of the mixture located in the compartment between adjacent electrodes;

- achieving the recommended current density on the electrodes that are optimal from the viewpoint of maximizing the utilization of electricity;

- prevent buckling and deformation of the inclined electrodes during discharge of the concrete mixture from a vehicle in a warming device. To reduce the shielding under the surface of the electrode vapor bubbles and to ensure uniformity of heating of the concrete mix in the sloping electrodes made a horizontal bandpass notch height in a checkerboard pattern. The height of the horizontal strip of the recess in the electrode size 8...10 mm is adopted from the condition of calculating the maximum diameter of the vapor bubble and ensure free passage on the opposite side of the electrode. As in the existing bunkers electroresistive concrete mix is established that the bubble motion is converted into a shell, starting with 5...6 cm from the bottom edge electrode, the cut performed by dividing the conductive surface areas of the same height. In this case, the vapor bubbles formed by heating the mixture under the electrodes pass through the band-pass cut-outs on the opposite side of the electrode and Conde is ciruits in subcooled areas of concrete.

For experimental verification of the attached design electroradiographic hopper with inclined electrodes (see figure 1).

The use of declared facilities can improve the uniformity of heating of the concrete mix, to reduce energy consumption and duration of heating.

Literature

1. Zilberberg C.J., and other Preliminary elektromotoren concrete mixture when the concrete in winter conditions. - M, stroiizdat, 1974, 220 S.

2. Gnera L.P., Villains L.V., P. raczkowski, Sheshukov UPON the Cooling and curing of the heated mixture. Tomsk: Publishing House Of Tomsk. University, 1984. - 232 S.

Electroresistive bunker cyclical steps, characterized in that the steel plate electrodes are installed with an inclination angle of 70...75° to the bottom and made a horizontal strip-cut height 8...10 mm, located at the height of the electrode through the 5 6 see...



 

Same patents:

FIELD: process engineering.

SUBSTANCE: invention relates to construction, namely, to concrete and reinforced concrete article drying chambers. Proposed chamber comprises walls, detachable translucent cover and heat power feed system. Chamber guard structure and said detachable cover are made of combined material including metal, asbestos sheet, foil with heat insulation provided with air layer confined by two layers of foil. Layer of asbestos at chamber inner walls is covered by foil. IR radiators, portable heat sensor are arranged at chamber bottom while water like with sprinklers is laid around the periphery. Electrical protection contact device is arranged ay chamber r top part.

EFFECT: decreased heat losses.

1 dwg

FIELD: process engineering.

SUBSTANCE: invention relates to construction, namely, to method of controlling concrete thermal treatment. Proposed device comprises heater to heat laid concrete mix by heating wire or electrodes, measure mix temperature by temperature pickups, and system for automatic control over concrete article heating. Said system is composed of nondestructive control electronic transducers and instruments, i.e. USB-1, Pulsar-2 to take readings directly from early concrete, heating transformer KTP, double-ended lamps, multichannel temperature, heating and data reading interval meter, bus line, feed and heating devices, registrator and computer.

EFFECT: higher accuracy of control, stabilised temperature difference and concrete article and ambient medium.

Curing room // 2454324

FIELD: process engineering.

SUBSTANCE: invention relates to construction and may be used for curing concrete articles. Proposed curing room comprises walls with inner flange, hydraulic gate frame mounted on wall edges, shield with inner surface provided with steam-and-water insulation coating and heat insulation, steam duct, and condensate drain chute. Hydraulic gate frame is made up of horizontal channels arranged horizontally along room walls to house elastic porous material for room sealing by absorbing condensed steam. Aforesaid shield is made up of carcass consisting of weight-reduced channels coated by heat-insulation material with inner cavities. Said shield serves to press elastic porous material against all edges of channel cavity.

EFFECT: high-reliability sealing.

2 cl, 6 dwg

FIELD: construction.

SUBSTANCE: method for strengthening treatment of concrete products includes exposure of alternating rotary magnetic field with specified value of its intensity and frequency at components used in composition of initial concrete mix, when exposure of alternating rotary magnetic field is provided for all components making concrete without exception after their combination into integral volume directly in the product item itself after realisation of initial mixture components curing operation. This exposure is realised in moulded product without its extraction from used curb. The item itself performs function of closing connecting link in magnetic circuit used for generation of field. Treatment is carried out at intensity of alternating magnetic field 1×104-3×106 a/m; range of its frequencies 20-70 Hz for 1.5-4.5 hours. Cycles of treatment are repeated twice: in 160-180 hours with a delay of 0.3-0.7 hr and in 480-500 hours with a delay of 0.1-0.2 hour. Device used to realise the method comprises circuit developing alternating magnetic field and electric windings-coils mounted on it and connected to external source of AC current supply. One of plates making magnetic conducting circuit has through slot, dimensions of which make it possible to install the concrete product itself in it together with curb used for its moulding, and its body when installed in circuit serves as closing connecting link that closes magnetic flow generated in it.

EFFECT: improved strength characteristics used to erect objects of concrete building structures.

2 cl, 2 dwg, 3 ex

FIELD: construction, particularly devices for thermal treatment of reinforced structures during in-situ structure erection with the use of automatic temperature condition control means.

SUBSTANCE: device comprises form, heat-sensing means, heaters and computer. Heat-sensing means are placed in form. Heaters are laid on reinforcing cage of monolithic reinforced concrete structure and fixed thereto. Heat-sensing means are linked to automatic digital power regulator including indication and control unit and digital control unit connected with control computer by means of signal converter. To provide visual control automatic power regulator is provided with concrete temperature display panel, which indicates concrete temperature in each measurement point and volumetrically weighed average concrete temperature.

EFFECT: decreased power inputs and possibility to control thermal field transformation after heater switching-on or switching-off in correspondence with thermal limiters of valid regulation documents.

2 cl, 3 dwg

FIELD: building industry; methods of production of the construction products at the building industry works.

SUBSTANCE: the invention is pertaining to the field of building industry, in particular, to the method of production of the construction products at the building industry works and may be used for manufacture of the reinforced concrete, including the spatial structures with the heat-insulating layer. The technical result of the invention is reduction of the power input, improvement of the quality and expansion of list of products. The method of manufacture of double-layer reinforced concrete products includes the consecutive formation of the constructive and the heat-insulating layers of the reinforced concrete and its thermal treatment. The heat-insulating layer with the average density of 450-500 kg/m3 made out of the vermiculite-concrete mixture with flowability of 3-5 cm is molded by the vibrobeam with the simultaneous its reinforcement by the woven net in top level. After the structure achieves the plastic strength of 0.015-0.025 MPa, then begin the molding the constructive layer and conduct the thermal treatment by the method of the contact heating from the side of the heat-insulating layer.

EFFECT: the invention ensures reduction of the power input, improvement of the quality and expansion of list of products.

FIELD: method and equipment for manufacturing gypsum plates.

SUBSTANCE: method involves the following steps: first step includes molding plate; second step includes hardening by hydration process until hydrated article is produced with hydration extent within the range from 33% to 80%; third step includes continuing hydration process in at least one rotating drum by rotating plate around central axis; fourth step includes drying process. Intermediate cutting process may be provided between second and third steps, said cutting process may be effectuated in accordance with wire principle. Apparatus has linear zone for partial hardening and hydration, and at least one hydration drum comprising central axis around which multiplicity of branches are arranged. Each branch in drum may be divided into multiplicity of levers, with surface of said levers making from about 50% to about 99% the surface of respective branch. Drum may have from 10 to 150 branches, preferably from 40 to 120 branches. Hardening and hydration zone and drum may be arranged in two axes extending in parallel with one another.

EFFECT: improved quality of articles, improved maintenance and operating conditions.

12 cl, 11 dwg

FIELD: building, particularly for concreting cast-in-place and precast reinforced concrete structures along with concrete curing temperature regulation.

SUBSTANCE: method involves laying and compacting concrete mix under continuous concrete mix curing temperature control; heating central concrete layers with heating reinforcement when outer concrete layers are in elasto-plastic state. Heating reinforcement is spaced a distance "a" from surface. The heating is carried out simultaneously with surface heat-shielding. Distance "a" is determined as a=δeq(tav-ts)/(ts-ta), m, where δeq - thickness of conditional equivalent concrete layer corresponding to surface thermal resistance, Rs, m; tav - time-average concrete temperature calculated by estimated time of heating directly in heating area, deg; ts - time-average temperature at concrete surface calculated by estimated heating time, deg; δeq is determined as δeq=Rs·λ·F, m, where Rs is heat resistance of rigging with form Rr including thermal resistance Ra of heat transfer from rigging to ambient air, h·deg/kcal; Rs=Rr+Ra=(δr/( λr·F))+(1/(α·F)), h·deg/kcal, where δr is thickness of rigging, m; λr is rigging heat conductivity factor kcal/(m·h·deg), α is rigging surface heat-transfer coefficient kcal/(m2·h·deg), λ is concrete(reinforced concrete) heat conductivity kcal/(m·h·deg); F=1m2 - rigging surface area for thermal resistance calculation, m2. Amount of heat Q used to heat part of member to be heated having length (height) of 1.0 m and cross-sectional width of 1.0 m is determined from Q=(tav-ts)(m+(τ·λ·F/a), where m is constant equal to 60-180 kcal/deg and τ is calculated heating time, hours. The heating reinforcement is heating wires or pipes adapted for hot water circulation.

EFFECT: reduced temperature stresses and prevention of crack formation during structure concreting, as well as possibility to regulate curing temperature.

4 cl, 1 ex, 4 dwg

FIELD: apparatus or processes for treating or working, namely curing, setting or hardening, the shaped articles.

SUBSTANCE: method for gypsum panel forming involves shaping the panel, hardening and hydrating thereof and drying the panel during panel rotation. Device to realize above method is also disclosed.

EFFECT: increased panel quality, decreased production and maintenance costs and improved operating conditions.

20 cl, 11 dwg

FIELD: building industry branches, namely apparatuses for heat treatment of constructions of reinforced concrete erected in building site with use of automatic control of heat treatment processes.

SUBSTANCE: apparatus includes concrete form having electric heating units mounted in its boards for convection-irradiation heating of concrete mixture and heating members mounted in bottom of concrete form for convection-irradiation heating; temperature pickups having individual control circuits and connected to inlets of heat regulators. Outlets of heat regulators are connected through switching units having magnetic starters with respective electric heating units. Each control circuit includes at least six temperature pickups placed in monolithic construction and pickup for measuring temperature of environmental air. Said pickups are connected with inlets of respective programmed heat regulator for supplying control signals.

EFFECT: enhanced quality of constructions.

3 cl, 4 dwg

FIELD: building industry branches, namely apparatuses for heat treatment of constructions of reinforced concrete erected in building site with use of automatic control of heat treatment processes.

SUBSTANCE: apparatus includes concrete form having electric heating units mounted in its boards for convection-irradiation heating of concrete mixture and heating members mounted in bottom of concrete form for convection-irradiation heating; temperature pickups having individual control circuits and connected to inlets of heat regulators. Outlets of heat regulators are connected through switching units having magnetic starters with respective electric heating units. Each control circuit includes at least six temperature pickups placed in monolithic construction and pickup for measuring temperature of environmental air. Said pickups are connected with inlets of respective programmed heat regulator for supplying control signals.

EFFECT: enhanced quality of constructions.

3 cl, 4 dwg

FIELD: apparatus or processes for treating or working, namely curing, setting or hardening, the shaped articles.

SUBSTANCE: method for gypsum panel forming involves shaping the panel, hardening and hydrating thereof and drying the panel during panel rotation. Device to realize above method is also disclosed.

EFFECT: increased panel quality, decreased production and maintenance costs and improved operating conditions.

20 cl, 11 dwg

FIELD: building, particularly for concreting cast-in-place and precast reinforced concrete structures along with concrete curing temperature regulation.

SUBSTANCE: method involves laying and compacting concrete mix under continuous concrete mix curing temperature control; heating central concrete layers with heating reinforcement when outer concrete layers are in elasto-plastic state. Heating reinforcement is spaced a distance "a" from surface. The heating is carried out simultaneously with surface heat-shielding. Distance "a" is determined as a=δeq(tav-ts)/(ts-ta), m, where δeq - thickness of conditional equivalent concrete layer corresponding to surface thermal resistance, Rs, m; tav - time-average concrete temperature calculated by estimated time of heating directly in heating area, deg; ts - time-average temperature at concrete surface calculated by estimated heating time, deg; δeq is determined as δeq=Rs·λ·F, m, where Rs is heat resistance of rigging with form Rr including thermal resistance Ra of heat transfer from rigging to ambient air, h·deg/kcal; Rs=Rr+Ra=(δr/( λr·F))+(1/(α·F)), h·deg/kcal, where δr is thickness of rigging, m; λr is rigging heat conductivity factor kcal/(m·h·deg), α is rigging surface heat-transfer coefficient kcal/(m2·h·deg), λ is concrete(reinforced concrete) heat conductivity kcal/(m·h·deg); F=1m2 - rigging surface area for thermal resistance calculation, m2. Amount of heat Q used to heat part of member to be heated having length (height) of 1.0 m and cross-sectional width of 1.0 m is determined from Q=(tav-ts)(m+(τ·λ·F/a), where m is constant equal to 60-180 kcal/deg and τ is calculated heating time, hours. The heating reinforcement is heating wires or pipes adapted for hot water circulation.

EFFECT: reduced temperature stresses and prevention of crack formation during structure concreting, as well as possibility to regulate curing temperature.

4 cl, 1 ex, 4 dwg

FIELD: method and equipment for manufacturing gypsum plates.

SUBSTANCE: method involves the following steps: first step includes molding plate; second step includes hardening by hydration process until hydrated article is produced with hydration extent within the range from 33% to 80%; third step includes continuing hydration process in at least one rotating drum by rotating plate around central axis; fourth step includes drying process. Intermediate cutting process may be provided between second and third steps, said cutting process may be effectuated in accordance with wire principle. Apparatus has linear zone for partial hardening and hydration, and at least one hydration drum comprising central axis around which multiplicity of branches are arranged. Each branch in drum may be divided into multiplicity of levers, with surface of said levers making from about 50% to about 99% the surface of respective branch. Drum may have from 10 to 150 branches, preferably from 40 to 120 branches. Hardening and hydration zone and drum may be arranged in two axes extending in parallel with one another.

EFFECT: improved quality of articles, improved maintenance and operating conditions.

12 cl, 11 dwg

FIELD: building industry; methods of production of the construction products at the building industry works.

SUBSTANCE: the invention is pertaining to the field of building industry, in particular, to the method of production of the construction products at the building industry works and may be used for manufacture of the reinforced concrete, including the spatial structures with the heat-insulating layer. The technical result of the invention is reduction of the power input, improvement of the quality and expansion of list of products. The method of manufacture of double-layer reinforced concrete products includes the consecutive formation of the constructive and the heat-insulating layers of the reinforced concrete and its thermal treatment. The heat-insulating layer with the average density of 450-500 kg/m3 made out of the vermiculite-concrete mixture with flowability of 3-5 cm is molded by the vibrobeam with the simultaneous its reinforcement by the woven net in top level. After the structure achieves the plastic strength of 0.015-0.025 MPa, then begin the molding the constructive layer and conduct the thermal treatment by the method of the contact heating from the side of the heat-insulating layer.

EFFECT: the invention ensures reduction of the power input, improvement of the quality and expansion of list of products.

FIELD: construction, particularly devices for thermal treatment of reinforced structures during in-situ structure erection with the use of automatic temperature condition control means.

SUBSTANCE: device comprises form, heat-sensing means, heaters and computer. Heat-sensing means are placed in form. Heaters are laid on reinforcing cage of monolithic reinforced concrete structure and fixed thereto. Heat-sensing means are linked to automatic digital power regulator including indication and control unit and digital control unit connected with control computer by means of signal converter. To provide visual control automatic power regulator is provided with concrete temperature display panel, which indicates concrete temperature in each measurement point and volumetrically weighed average concrete temperature.

EFFECT: decreased power inputs and possibility to control thermal field transformation after heater switching-on or switching-off in correspondence with thermal limiters of valid regulation documents.

2 cl, 3 dwg

FIELD: construction.

SUBSTANCE: method for strengthening treatment of concrete products includes exposure of alternating rotary magnetic field with specified value of its intensity and frequency at components used in composition of initial concrete mix, when exposure of alternating rotary magnetic field is provided for all components making concrete without exception after their combination into integral volume directly in the product item itself after realisation of initial mixture components curing operation. This exposure is realised in moulded product without its extraction from used curb. The item itself performs function of closing connecting link in magnetic circuit used for generation of field. Treatment is carried out at intensity of alternating magnetic field 1×104-3×106 a/m; range of its frequencies 20-70 Hz for 1.5-4.5 hours. Cycles of treatment are repeated twice: in 160-180 hours with a delay of 0.3-0.7 hr and in 480-500 hours with a delay of 0.1-0.2 hour. Device used to realise the method comprises circuit developing alternating magnetic field and electric windings-coils mounted on it and connected to external source of AC current supply. One of plates making magnetic conducting circuit has through slot, dimensions of which make it possible to install the concrete product itself in it together with curb used for its moulding, and its body when installed in circuit serves as closing connecting link that closes magnetic flow generated in it.

EFFECT: improved strength characteristics used to erect objects of concrete building structures.

2 cl, 2 dwg, 3 ex

Curing room // 2454324

FIELD: process engineering.

SUBSTANCE: invention relates to construction and may be used for curing concrete articles. Proposed curing room comprises walls with inner flange, hydraulic gate frame mounted on wall edges, shield with inner surface provided with steam-and-water insulation coating and heat insulation, steam duct, and condensate drain chute. Hydraulic gate frame is made up of horizontal channels arranged horizontally along room walls to house elastic porous material for room sealing by absorbing condensed steam. Aforesaid shield is made up of carcass consisting of weight-reduced channels coated by heat-insulation material with inner cavities. Said shield serves to press elastic porous material against all edges of channel cavity.

EFFECT: high-reliability sealing.

2 cl, 6 dwg

FIELD: process engineering.

SUBSTANCE: invention relates to construction, namely, to method of controlling concrete thermal treatment. Proposed device comprises heater to heat laid concrete mix by heating wire or electrodes, measure mix temperature by temperature pickups, and system for automatic control over concrete article heating. Said system is composed of nondestructive control electronic transducers and instruments, i.e. USB-1, Pulsar-2 to take readings directly from early concrete, heating transformer KTP, double-ended lamps, multichannel temperature, heating and data reading interval meter, bus line, feed and heating devices, registrator and computer.

EFFECT: higher accuracy of control, stabilised temperature difference and concrete article and ambient medium.

FIELD: process engineering.

SUBSTANCE: invention relates to construction, namely, to concrete and reinforced concrete article drying chambers. Proposed chamber comprises walls, detachable translucent cover and heat power feed system. Chamber guard structure and said detachable cover are made of combined material including metal, asbestos sheet, foil with heat insulation provided with air layer confined by two layers of foil. Layer of asbestos at chamber inner walls is covered by foil. IR radiators, portable heat sensor are arranged at chamber bottom while water like with sprinklers is laid around the periphery. Electrical protection contact device is arranged ay chamber r top part.

EFFECT: decreased heat losses.

1 dwg

Up!