CN113957805A

CN113957805A - Installation device and method for hanging water supply and drainage pipeline under bridge

Info

Publication number: CN113957805A
Application number: CN202111410913.7A
Authority: CN
Inventors: 张放明; 郑全兴; 任九天; 刘锐; 张建; 华杰
Original assignee: Jiangsu Changjiang Water Co ltd
Current assignee: Jiangsu Changjiang Water Co ltd
Priority date: 2021-11-25
Filing date: 2021-11-25
Publication date: 2022-01-21
Anticipated expiration: 2041-11-25
Also published as: CN113957805B

Abstract

The invention discloses a device and a method for mounting a water supply and drainage pipeline hung below a bridge in the field of water supply and drainage, wherein the device comprises a cantilever workbench hung on the side surface of a bridge, the cantilever workbench is mounted on a counterweight trolley, the counterweight trolley is arranged on the bridge floor of the bridge, a support is arranged on the inner side of the outer edge of the bridge, the support is mounted on a bridge plate and is positioned below the bridge floor, and an extension pipe is arranged on the support in a matched manner; the cantilever working platform and the balance weight trolley are adopted, the problems of hoisting and positioning of the tap water pipeline and butt welding are solved, and the cantilever working platform and the balance weight trolley can be used for hanging and installing the bridge water supply and drainage pipeline.

Description

Installation device and method for hanging water supply and drainage pipeline under bridge

Technical Field

The invention relates to a device and a method for installing a bridge water service pipe in the field of water supply and drainage.

Background

The water supply network is one of the important life lines of urban construction and is an infrastructure related to civil life, and once a water supply pipeline is damaged, the life and production of people can be seriously influenced, so that the construction is seriously carried out according to the current national standard, and the construction quality is strictly controlled. In the prior art, water supply and drainage pipelines are arranged from the underwater or hung below a bridge body of a bridge. The construction cost of pipe distribution from the water surface is high, and the maintenance is inconvenient; the lower suspension is selected below the bridge body, a floating bridge is needed, the cost for building the floating bridge is high, the reinforced concrete of the bridge body has internal and external light and smooth surface, no hole can be drilled at any place of the bridge body, the structure safety is affected, auxiliary tools such as a construction scaffold and the like cannot be fixed on the bridge body, and the bridge body has no stress point; and in order to reduce rain, the water supply and drainage pipeline needs to fall on the support below the bridge plate, and the steel pipe cannot fall on the support by hoisting of a hoisting machine.

Disclosure of Invention

The invention aims to provide a device and a method for mounting a water supply and drainage pipeline hung below a bridge.

In order to achieve the purpose, the invention provides a mounting device for hanging a water supply and drainage pipeline under a bridge, which comprises a cantilever workbench hung on the side face of a bridge, wherein the cantilever workbench is mounted on a counterweight trolley, the counterweight trolley is arranged on the bridge floor of the bridge, a support is arranged on the inner side of the outer edge of the bridge, the support is mounted on a bridge plate and is positioned below the bridge floor, and an extension pipe is arranged on the support in a matched manner.

Compared with the prior art, the invention has the beneficial effects that a set of cantilever workbench and a set of balance weight trolley are respectively arranged at two ends of a hoisted steel pipe, the cantilever workbench can be hung below the side face of a bridge, so that a constructor can be positioned below the bridge through the cantilever workbench, an extension pipe can be inserted on a support, the length of the support is prolonged and extends out of the side face of the bridge, a hoisting machine can conveniently hoist the steel pipe on the extension pipe, the constructor can send the steel pipe placed on the extension pipe onto the support through a chain block to realize hoisting and positioning of the steel pipe, and after one section of the steel pipe is installed and positioned, the balance weight trolley can drive the cantilever workbench to move towards the next installation section after the extension pipe is dismantled; the cantilever working platform and the balance weight trolley are adopted, the problems of hoisting and positioning of the tap water pipeline and butt welding are solved, and the cantilever working platform and the balance weight trolley can be used for hanging and installing the bridge water supply and drainage pipeline.

As a further improvement of the invention, the cantilever workbench comprises a rectangular platform, the outer side edge of the rectangular platform is provided with a fixed plate attached with channel steel, the other three sides of the rectangular platform are provided with lower guardrails, the top of the fixed plate is provided with a top plate with a keel, the top plate is connected with a connecting plate, the connecting plate is connected with a counterweight cart through bolts, one side of the fixed plate is provided with an upper guardrail, a space is reserved between the top plate and the upper guardrail, the inner side surface of the fixed plate is provided with a ladder stand which is arranged between the connecting plate and the upper guardrail, so that four sides of the rectangular platform are surrounded by the fixed plate and the lower guardrail, constructors can safely stand in the fixed plate to carry out construction operation, and the fixed plate, the top plate and the connecting plate enable the rectangular platform to be connected with the counterweight cart, so that the counterweight cart can drive the cantilever workbench to move along a bridge floor, go up the guardrail and only set up the one side, just can be pushed cantilever workstation and bridge below in the side face like this at steel pipe both ends, the constructor of being convenient for pushes the steel pipe into the support through chain block on, and then realizes the installation and construction of bridge below.

As a further improvement of the invention, the counterweight trolley comprises a base, wherein a counterweight block with the mass not less than 1 ton is arranged on the base, a directional wheel is arranged on the bottom of the base, and a brake rod is arranged on the part, close to the connecting plate, of the top plate, so that the counterweight trolley can move along a straight line by the directional wheel to drive the cantilever workbench to move in place along the bridge, the counterweight block can ensure that a constructor still keeps balance when operating after entering the cantilever workbench, the safety is ensured, and the brake rod compresses the rest bridge floors during construction, so that the counterweight trolley cannot move, and the construction safety is further ensured.

In order to achieve the aim, the invention provides a method for installing a water supply and drainage pipeline hung below a bridge, which comprises the following steps: step 1, manufacturing and installing a bracket; step 2, hoisting and positioning the pipeline; step 3, aligning and welding the pipelines; and 4, installing the pipeline expansion joint.

As a further improvement of the invention, the specific content of the step 1 is as follows:

the channel-section steel is blanked according to the drawing size earlier, prefabricate, and the support is whole to be L shape, and the perpendicular distance 1.1m below the bridge plate is apart from to the cross arm of support, and the tail end of cross arm is in the bridge plate outside along the inboard of bridge, and is 0.3m apart from the horizontal distance of bridge plate outside along, pegs graft the cross arm end at the support with the extension pipe, with the scaffold weldment in pre-buried and the bridge body steel sheet, all supports and steel member carry out anticorrosive treatment before the installation and after the scaffold weldment, the secondary anticorrosive treatment will be carried out to the splice.

As a further improvement of the invention, the specific content of the step 2 is as follows:

step 2.1, two sets of cantilever working platforms and two sets of balance weight trolleys are prepared to be in place, constructors enter a rectangular platform of the cantilever working platform through a ladder stand, an automobile crane slowly lifts steel pipes after the bridge floor is stopped and stabilized by supporting legs, 1 traction rope is bound at two ends of each steel pipe, and the posture of a pipeline is adjusted during lifting;

step 2.2, bridge deck constructors adjust the pipeline to be parallel to the bridge body through the traction ropes, and slowly move the pipeline outwards to the outer edge of the bridge, so that the horizontal distance between the steel pipe and the bridge railing is 1 m;

step 2.3, after the steel pipe is integrally stabilized, informing constructors positioned on the rectangular platform below the bridge to prepare and transmit a traction rope to the constructors on the rectangular platform, pulling the traction rope to adjust the state of the steel pipe, slowly landing the steel pipe on an extension pipe of the bracket, and then respectively pulling two ends of the steel pipe into a space between a ladder stand and a bridge body of the cantilever workbench;

and 2.4, welding a retaining ring at the upper end of the pre-buried steel plate to vertically hang a chain block, respectively adjusting the radial distance of the front end and the rear end of the steel pipe by using the chain block after the nylon hanging strip of the chain block ties the steel pipe, and after the adjustment is finished, untying the steel wire rope and pulling the rope to inform bridge deck personnel to withdraw.

As a further improvement of the present invention, the specific content of step 3 is as follows:

step 3.1, respectively installing a portal frame on the supports at the front end and the rear end of the pipeline to be installed, hanging a chain block on the middle point of the portal frame, and tying the block on a steel pipe;

3.2, pulling up the front end and the rear end of the steel pipe by using a chain block by utilizing a lever principle, then placing a pipe bracket with a pipe hoop above a support, wherein a color wire is pulled at the placing position to ensure that the central line of the steel pipe meets the design requirement, placing 8 pipe brackets each time, and after the steel pipe is positioned and welded, firmly welding the pipe brackets and carrying out anti-corrosion treatment;

and 3.3, after the steel pipe is in place, additionally matching a chain block at the front end of the steel pipe for adjusting the axial displacement of the steel pipe, so that the steel pipe can be in butt welding with the steel pipe installed in front.

And 3.4, after the pipeline hoisting and welding work is finished, transferring all construction equipment and tool materials on the cantilever working platform to the bridge floor, withdrawing all constructors on the cantilever working platform to the bridge floor, moving the balance weight cart to move the cantilever working platform to the next working section, and repeating the steps.

As a further improvement of the present invention, the specific content of step 3.3 is as follows:

the coarse ramie tape of surface winding of steel pipe for protect pipeline surface coating, again with nylon fiber suspender multiturn, closely twine in the middle of the ramie tape, after buckling chain block's lifting hook and suspender latch closure jail, adjust calabash chain cable and suspender length, thereby adjust the axial interval of pipeline terminal surface butt joint, after reaching the regulation requirement to the mouth precision, immediately with the electric welding multiple spot positioning welding on the hoop welding seam, with fixed pipeline terminal surface, the solder joint is no less than 3, spot welding length is 80 mm ~ 100mm, the spot welding interval is not more than 400 mm, the welding seam height is 2mm ~ 4 mm.

As a further improvement of the present invention, the specific content of step 4 is as follows:

the expansion joint is tested before being installed; the expansion joint is connected with the steel pipe by adopting flanges, the flanges are concentric with the pipeline, the two flanges are parallel, first to second welding interfaces adjacent to two sides of the flange interface are welded after the flanges are fastened by bolts; the water supply and drainage pipeline composed of steel pipes is respectively provided with an expansion joint at the two ends and the middle part.

Drawings

Fig. 1 is a schematic view of a hoisting structure of the invention.

Fig. 2 is a schematic diagram of a hoisting structure of the invention.

Fig. 3 is a schematic view of the installation structure of the present invention.

Fig. 4 is a first structural schematic diagram of the counterweight trolley and the cantilever workbench according to the invention.

Fig. 5 is a schematic structural view of the counterweight trolley and the cantilever workbench according to the invention.

FIG. 6 is a schematic view of the stent structure of the present invention.

The device comprises a large bridge 1, a cantilever workbench 2, a counterweight trolley 3, a truck crane 4, a steel pipe 5, a brake rod 6, an extension pipe 7, a support 8, a rectangular platform 9, a lower guardrail 10, a base 11, a directional wheel 12, a counterweight 13, a top plate 14, a fixing plate 15, a connecting plate 16, a ladder 17, an upper guardrail 18, a pipe hoop 19, a pipe bracket 20 and a cross arm 21.

Detailed Description

The invention is further described below with reference to the accompanying drawings:

the installation device for hanging the water supply and drainage pipeline under the bridge as shown in fig. 1-6 comprises a cantilever workbench 2 hung on the side surface of a bridge 1, wherein the cantilever workbench 2 is installed on a counterweight trolley 3, the counterweight trolley 3 is arranged on the bridge floor of the bridge 1, a support 8 is arranged on the inner side of the outer edge of the bridge 1, the support 8 is installed on a bridge plate and is positioned below the bridge floor, and an extension pipe 7 is arranged on the support 8 in a matched manner.

Cantilever workstation 2 includes rectangle platform 9, the outside limit of rectangle platform 9 is provided with fixed plate 15 of additional channel-section steel, all the other trilateral guardrails 10 down that are provided with of rectangle platform 9, the top of fixed plate 15 is provided with roof 14 that has the keel, and roof 14 links to each other with connecting plate 16, connecting plate 16 links to each other with counter weight shallow 3 through the bolt, one side of fixed plate 15 is provided with guardrail 18, leave the interval between connecting plate 16 and the last guardrail 18, cat ladder 17 is installed to the medial surface of fixed plate 15, cat ladder 17 sets up between connecting plate 16 and last guardrail 18.

The counterweight trolley 3 comprises a base 11, a counterweight block 13 with the mass not less than 1 ton is arranged on the base 11, an orientation wheel 12 is arranged on the bottom of the base 11, and a brake rod 6 is arranged on the part, close to a connecting plate 16, of the top plate 14.

A method for installing a water supply and drainage pipeline of a bridge 1 as shown in fig. 1-6, comprising the following steps:

step 1, manufacturing and installing a support 8:

the channel steel is blanked according to the drawing size firstly, prefabricating is carried out, the support 8 is integrally L-shaped, the vertical distance between a cross arm 21 of the support 8 and the lower side of a bridge plate is 1.1m, the tail end of the cross arm 21 is arranged on the inner side of the outer edge of the bridge plate of the bridge 1, the horizontal distance between the cross arm 21 of the support 8 and the outer edge of the bridge plate is 0.3m, an extension pipe 7 is inserted into the end of the cross arm 21 of the support 8, the support 8 is welded on a steel plate in an embedded bridge body, all the supports 8 and steel members are subjected to corrosion prevention treatment before installation, and after the supports 8 are welded, secondary corrosion prevention treatment is carried out on the welding positions.

Step 2, hoisting and positioning the pipeline:

step 2.1, two sets of cantilever working platforms and two sets of counterweight trolleys 3 are prepared to be in place, constructors enter the rectangular platform 9 of the cantilever working platform 2 through the crawling ladder 17, the automobile crane 4 slowly lifts the steel pipe 5 after the stable supporting legs are stopped on the bridge floor, 1 traction rope is bound at two ends of the steel pipe 5, and the posture of the pipeline is adjusted during lifting;

step 2.2, bridge deck constructors adjust the pipeline to be parallel to the bridge body through the traction rope and slowly move the pipeline to the outer edge of the bridge, so that the horizontal distance between the steel pipe 5 and the bridge railing is 1 m;

step 2.3, after the steel pipe 5 is integrally stabilized, informing constructors below the bridge on the rectangular platform 9 of preparing and transmitting a traction rope to the constructors on the rectangular platform 9, pulling the traction rope to adjust the state of the steel pipe 5, slowly landing the steel pipe 5 on an extension pipe 7 of a bracket 8, and then respectively pulling two ends of the steel pipe 5 into a space between a ladder 17 of the cantilever workbench 2 and the bridge body;

and 2.4, welding a retaining ring at the upper end of the pre-buried steel plate, hanging a chain block up and down, respectively adjusting the radial distance of the front end and the rear end of the steel pipe 5 by using the chain block after the steel pipe 5 is tied by a nylon hanging strip of the chain block, and informing bridge deck personnel to withdraw after the adjustment is finished.

Step 3, aligning and welding the pipelines:

step 3.1, respectively installing a portal frame on the supports 8 at the front end and the rear end of the pipeline to be installed, hanging a chain block on the middle point of the portal frame, and tying the block on the steel pipe 5;

3.2, pulling up the front end and the rear end of the steel pipe 5 by using a chain block by utilizing a lever principle, then placing the pipe bracket 20 with the pipe hoop 19 above the bracket 8, wherein the placing position needs to be provided with a color stay wire to ensure that the central line of the steel pipe 5 meets the design requirement, placing 8 pipe brackets 20 each time, and after the steel pipe 5 is positioned and welded, firmly welding the pipe brackets 20 and carrying out antiseptic treatment;

and 3.3, after the steel pipe 5 is in place, additionally matching a chain block at the front end of the steel pipe 5, and adjusting the axial displacement of the steel pipe 5 to ensure that the steel pipe 5 can be butt-welded with the steel pipe 5 installed in front, winding a coarse linen belt on the surface of the steel pipe 5 to protect the surface coating of the pipeline, winding a nylon fiber sling in the middle of the linen belt in a multi-turn and tight manner, firmly fastening a lifting hook of the chain block with a sling ring, adjusting the lengths of a chain cable and the sling, and thus adjusting the axial distance between the end faces of the pipeline, and immediately performing multi-point positioning welding on a circumferential welding line by electric welding to fix the end face of the pipeline after the butt-welding precision meets the specified requirement, wherein the number of welding points is not less than 3, the spot welding length is 80-100 mm, the spot welding distance is not more than 400 mm, and the height of the welding line is 2-4 mm.

And 3.4, after the pipeline hoisting and welding work is finished, all the construction equipment and tool materials on the cantilever working platform are transferred to the bridge floor, all constructors on the cantilever working platform 2 are evacuated to the bridge floor, and the counterweight trolley 3 is moved to move the cantilever working platform to the next working section to repeat the steps.

And 4, installing a pipeline expansion joint:

the expansion joint is tested before being installed; the telescopic joint is connected with the steel pipe 5 by adopting flanges, the flanges are concentric with the pipeline, the two flanges are parallel, first to second welding interfaces adjacent to two sides of the flange interface are welded after the flanges are fastened by bolts; and the water supply and drainage pipeline consisting of the steel pipes 5 is respectively provided with an expansion joint at the two ends and the middle part.

In the invention, the size of a base 11 platform of the counterweight trolley 3 is 2m multiplied by 2.6m, the main structure of the counterweight trolley 3 is welded by 10 # channel steel and 50 multiplied by 5 angle steel, four corners of the base 11 are respectively provided with a directional wheel 12 with the diameter of 10cm so as to be convenient for the trolley to move, a concrete precast block with the total mass not less than 1000kg is loaded on the base 11 platform to serve as a counterweight to enhance the stability of the trolley, the counterweight trolley 3 is provided with a brake rod 6 to limit the movement of the trolley during braking, the platform can not move when constructors perform construction operation, and the construction safety is ensured. Cantilever work platform below the bridge floor is the rectangle, and length 3.2m, width 2.6m adopt specification 10 # channel-section steel and the angle steel of 50 x 5 to weld and form, cantilever work platform and counter weight shallow 3 are connected with 10 # channel-section steel to welding shaped steel cat ladder 17, shaped steel cat ladder 17 and railing outside clear distance are not less than 1.2m, for the protection bridge floor railing, prevent the scraping. The cantilever working platform is convenient for the welding construction of the steel pipes 5, the distance between the cantilever working platform and the lower part of the bridge plate is about 1.8m, a group of cantilever working platforms are respectively arranged at two ends of the welded steel pipes 5 below the bridge floor, and the counterweight trolley 3 is moved through manpower to drive the working platform under the bridge to move along the bridge body in parallel, so that the pipeline is conveniently hoisted and positioned. Constructor ties the safety belt, and the safety belt is just fixed reliable on the shaped steel back at 3 tops of counter weight shallow, ensures that operating personnel is under construction safety in the air.

When the support 8 is installed, firstly, channel steel is blanked according to the drawing size and prefabricated, the support 8 is integrally L-shaped and consists of a 22 # B channel steel, two channel steel of the support 8 are connected with a 800mm x 300mm steel plate base 11 which is embedded in a lower bridge body of a bridge in a welding mode, and the support 8 is installed according to the paid-off elevation.

The length of the blanking cross arm 21 is about 2.1m, the vertical distance from the lower part of the bridge plate is 1.1m, the tail end of the cross arm 21 is arranged at the inner side of the outer edge of the bridge plate, and the horizontal distance from the tail end of the cross arm 21 to the outer edge of the bridge plate is 0.3m, so that the service life of the bracket 8 is prevented from being influenced by rain corrosion; all the supports 8 and the steel members are subjected to corrosion prevention treatment before installation, and after the supports 8 are welded, secondary corrosion prevention treatment is carried out on the welding positions.

Considering the safety of hoisting, the pipeline to be hoisted can not be too long, the pipeline is transported to DN800 steel pipes 5 on the bridge floor, the length of each steel pipe 5 is 12m, 2 groups are butt-welded on the bridge floor, after welding forming, the length of the hoisting pipeline is 24m, and the total hoisting mass is not more than 6 t.

Before hoisting, two ends of about 20m are respectively provided with 1 set of cantilever working platform and a balance weight trolley 3, and the distance between the two sets of the cantilever working platform and the balance weight trolley is 15 m-20 m. A25 t automobile crane 4 is selected as a hoisting machine, after the landing legs are stopped and stabilized on the bridge floor, the steel pipe 5 is hoisted slowly, 1 nylon fiber traction rope with the diameter of 2cm is bound at two ends of the steel pipe 5, the length of the nylon fiber traction rope is about 10m, and the nylon fiber traction rope is used for adjusting the posture of a pipeline during hoisting. Bridge floor constructor is on a parallel with the axle body through pulling the rope with pipeline adjustment, move to the outer border of bridge slowly, apart from about 1m of bridge railing horizontal distance, it is stable for a while, inform the constructor of bridge below (constructor walks to cat ladder 17 through roof 14 on, reentrant rectangle platform 9 is last, rectangle platform 9 is in the bridge below) ready work back, will pull the rope and give the constructor of bridge below, adjust the state of steel pipe 5, steel pipe 5 lands slowly on extension pipe 7 (adopting the rectangular pipe) of support 8, then draw the space between shaped steel cat ladder 17 and the axle body respectively with the both ends of steel pipe 5.

The cantilever support 8 cross arm 21 is on the inner side of the outer edge of the bridge plate, the running water steel pipe 5 can not land on the cross arm 21, rectangular pipes are sleeved on the support 8 of the pipeline to be installed, the length of the cross arm 21 is prolonged, the length of each rectangular pipe is 1.6m, 2 holes are drilled in one end of each rectangular pipe, the first hole is 5 cm from the pipe end, the hole distance is 20cm, and the hole diameter is 12mm, the rectangular pipes are fastened on the cantilever support 8 through bolts below the support 8, the length is prolonged by about 1m and overlapped by 0.6m, 8 rectangular pipes are installed in total, the steel pipe 5 falls on each rectangular pipe during hoisting, a buckle ring is welded at the upper end of a pre-buried 800mm multiplied by 300mm steel plate and used for hanging a bridge floor, the radial distances of the front end and the rear end of the steel pipe 5 are respectively adjusted, and after the steel pipe 5 is tied by a nylon sling of the chain hoist, the nylon sling, a steel wire rope and a traction rope on the pipeline are untied, and a person is informed to withdraw.

Each support 8 is provided with a pipe hoop 19, the pipe hoop 19 is divided into two semicircles in parallel, the pipe hoop 19 at the lower part is welded on a pipe support 20, the groove of the pipe support 20 has the minimum distance of 8cm from the support 8, no stress point is arranged at the upper part, and the clear distance of a pipeline is only about 20cm, so a simple portal frame is required to be arranged on the support 8 at the front end of the steel pipe 5 to be arranged, a chain block is hung on the middle point of the portal frame, a lifting hook is removed because of insufficient stroke, the block is tied on the steel pipe 5, the front end of the steel pipe 5 is pulled up by the chain block by utilizing the lever principle, then the pipe support 20 with the pipe hoop 19 is arranged above the support 8, a colored wire is required to be arranged at the position, the central line of the steel pipe 5 meets the design requirement, the same method is used, the tail end of the steel pipe 5 to be arranged is lifted by the simple portal frame, the pipe support 20 is arranged at the tail end of the steel pipe 5, 8 pipe supports 20 are arranged each time, and the pipeline is positioned and welded, and (4) firmly welding the pipe bracket 20 and performing antiseptic treatment. After the steel pipe 5 takes one place, the steel pipe needs to be butt-welded with a pipeline installed in front, another 1 hand chain block is used for finely adjusting the axial displacement of the pipeline in a matching way at the front end of the pipeline, when the axial displacement of the pipeline is adjusted, a rough linen belt is wound on the surface of a newly-hoisted pipeline and used for protecting the surface coating of the pipeline, then nylon fiber slings are wound in the middle of the linen belt in a multi-turn and tight winding way, after a hoist lifting hook is firmly buckled with the slings, the length of a chain cable and the slings of the hoist is adjusted, so that the axial distance of butt joint of the end faces of the pipeline is adjusted, after the butt-joint precision meets the specified requirement, the steel pipe is immediately welded on circumferential welding lines in a multi-point positioning way by electric welding, so that the end faces of the pipeline are fixed, the number of welding points is not less than 3, the spot welding length is 80-100 mm, the spot welding distance is not more than 400 mm, and the height of the welding lines is 2-4 mm.

The circumferential welding seam of the pipeline is constructed and welded according to a welding process instruction, the distance between the circumferential welding seam and the support 8 is noticed, the clear distance is not less than 100mm, the height, the width, the undercut and the misalignment size of the welding seam are measured by using a welding seam gauge and a steel ruler every time one welding seam is finished, the appearance quality of the welding seam is checked port by port, after the welding of the steel pipe 5 is finished, the quality of the welding seam is detected by 100% of X-ray flaw detection, the defects of cracks, air holes, slag inclusion and the like do not exist in the welding seam, and the welding quality of the welding seam meets the requirements of the current relevant national specifications. After the detection items reach the standard, the rectangular steel pipe 5 and the chain block suspension system are dismantled, the surface of the steel pipe 5 damaged by hoisting is repainted, the surface of the circumferential weld of the pipeline, the weld of the pipe hoop 19 and the nearby area are cleaned, the upper semi-circular pipe hoop 19 is connected with the lower semi-circular pipe hoop 19 through bolts, the contact surface of the pipe hoop 19 and the pipeline is smooth and clean, the pipeline is prevented from rolling, but no jamming phenomenon exists in the axial direction, and the flexibility and freedom of the pipeline are ensured.

After the pipeline hoisting and welding work in the section is finished, all construction equipment and tool materials on the cantilever working platform are transferred to the bridge floor, all workers below the bridge floor withdraw from the bridge floor, and the counterweight trolley 3 is moved to move the cantilever working platform to the next working section to repeat the construction method.

The steel pipe 5 is exposed in the air, is influenced by factors such as temperature, wind load, difference settlement caused by different base rigidity and the like, is easy to deform, and different stresses appear in the axial direction and the radial direction of the pipeline, so that the pipeline is damaged. The expansion joint is a weak link in the pipeline and is hung below the bridge floor, once the expansion joint is damaged and cannot be repaired, the pressure of the conveyed tap water is high, the requirement on the sealing performance of the expansion joint is also high, and higher requirements are provided for the quality of products and the quality of installation. The expansion joint is tested before being installed, the expansion joint is pre-stretched or compressed firstly, the expansion performance of the expansion joint is tested, the sealing rubber ring is straight, has no distortion and is correctly positioned, and the expansion joint can freely expand and maintain the sealing performance within the effective expansion range. The telescopic joint and the steel pipe 5 are connected by flanges, the flanges are concentric with the pipeline and parallel between the two flanges, and the first welding interface to the second welding interface which are adjacent to the two sides of the flange interface can be welded after the flanges are fastened by bolts. The expansion joint is also coaxial with the pipeline, and the installation error of the pipe position cannot be adjusted by using the axial, radial and torsional deformation of the expansion joint. Because the bridge approach and the bridge body main foundation have different rigidity, the pipeline laid on the approach section and the pipeline hung below the bridge can be deformed due to differential settlement, when the concrete thrust pier is poured on the approach section, the foundation is tamped, and the steel pipe 5 is prevented from generating radial stress and damaging the expansion joint due to foundation settlement after the pipeline is filled with water. The method is characterized in that 3 limiting expansion joints are arranged on the whole length of a pipeline on a bridge, the adjusting range of each expansion joint is not more than 150mm, the expansion joints are arranged, the safe operation of the pipeline is guaranteed, the maintenance of the pipeline is facilitated, the expansion joints are comprehensively considered, 1 expansion joint is arranged on each of two banks of a river, the hanging point of each expansion joint is about 200m away from the 5 initial ends of steel pipes, the expansion joints on the two banks are still arranged above a land area in dry seasons, scaffolds can be erected, and the maintenance of the expansion joints is facilitated. And 1 expansion joint is arranged near the center point of the bridge and is about 400m away from the other 2 expansion joints.

The invention can be used for the condition that the water surface under the bridge cannot erect the floating bridge or the erection cost is too high, the bridge body is flat and smooth, has no ideal supporting point, and under the condition that constructors can not enter the operation under the bridge without the help of external conditions, the device of the cantilever working platform 2+ the counterweight trolley 3 is adopted to assist the construction, thereby solving the problems of bracket installation, pipeline hoisting in place, pipeline butt welding and the like. The problem of pipeline flexible deformation has been successfully solved to reasonable setting expansion joint, can experience the test of severe cold extreme weather, and the pipeline operates steadily, has guaranteed people normal life and production water.

The present invention is not limited to the above embodiments, and based on the technical solutions of the present disclosure, those skilled in the art can make some substitutions and modifications to some technical features without creative efforts according to the disclosed technical contents, and these substitutions and modifications are all within the protection scope of the present invention.

Claims

1. an installation device for hanging water supply and drainage pipes under a bridge, characterized in that: comprising a cantilever workbench suspended on the side of the bridge, the cantilever workbench is installed on a counterweight cart, and the counterweight cart is arranged on the bridge The outer and inner sides of the bridge are provided with brackets, the brackets are installed on the bridge deck and below the bridge deck, and the brackets are provided with extension pipes.

2 . The installation device for water supply and drainage pipes hanging under a bridge according to claim 1 , wherein the cantilever workbench comprises a rectangular platform, and the outer side of the rectangular platform is provided with a fixing plate with additional channel steel. 3 . , the remaining three sides of the rectangular platform are provided with lower guardrails, the top of the fixed plate is provided with a top plate with a keel, the top plate is connected with the connecting plate, the connecting plate is connected with the counterweight cart through bolts, the fixed An upper guardrail is arranged on one side of the plate, and a space is left between the top plate and the upper guardrail. A climbing ladder is installed on the inner side of the fixed plate, and the climbing ladder is arranged between the connecting plate and the upper guardrail.

3 . The installation device for water supply and drainage pipes under a bridge according to claim 2 , wherein the counterweight cart comprises a base, and the base is provided with a counterweight with a mass of not less than 1 ton. 4 . The bottom of the base is provided with a directional wheel, and the part of the top plate close to the connecting plate is provided with a brake lever.

4. An installation method of a water supply and drainage pipeline hanging under a bridge, characterized in that: using the installation device of a water supply and drainage pipeline hanging under the bridge described in any one of claims 1-3, comprising the following steps:

Step 1, make and install the bracket;

Step 2, the pipeline is hoisted and placed in place;

Step 3, pipe butt joint, welding;

Step 4, installation of pipe expansion joints.

5. The installation method of a water supply and drainage pipeline under a bridge according to claim 4, wherein the specific content of the step 1 is as follows:

First cut the channel steel according to the size of the drawing and prefabricate it. The bracket is L-shaped as a whole. The vertical distance between the cross arm of the bracket and the bottom of the bridge deck is 1.1m. The horizontal distance between the outer edge of the plate is 0.3m, the extension pipe is inserted into the cross arm end of the bracket, and the bracket is welded to the steel plate embedded in the bridge body. Secondary anti-corrosion treatment should be carried out at the weld.

6. The installation method of a water supply and drainage pipeline under a bridge according to claim 5, wherein the specific content of the step 2 is as follows:

Step 2.1, two sets of cantilever work platform and counterweight trolley are ready to be in place. The construction personnel enter the rectangular platform of the cantilever workbench through the ladder. After the truck crane stops the outriggers on the bridge deck, slowly lift the steel pipe , Bind a traction rope at both ends of the steel pipe to adjust the posture of the pipe when lifting;

In step 2.2, the bridge deck construction personnel adjust the pipeline parallel to the bridge body through the traction rope, and slowly move outward to the outer edge of the bridge, so that the horizontal distance between the steel pipe and the bridge railing is 1m;

Step 2.3, after the steel pipe is stabilized as a whole, notify the construction personnel on the rectangular platform under the bridge to make preparations and pass the traction rope to the construction personnel on the rectangular platform. Pull the traction rope to adjust the state of the steel pipe, and the steel pipe slowly landed on the platform. On the extension pipe of the bracket, then pull the two ends of the steel pipe into the space between the ladder of the cantilever workbench and the bridge body;

Step 2.4: Weld the buckle on the upper end of the embedded steel plate and hang the chain hoist up and down. After the nylon sling of the chain hoist is used to fasten the steel pipe, use the chain hoist to adjust the radial distance of the front and rear ends of the steel pipe respectively. After the adjustment is completed, the wire rope and traction are unfastened. Rope, notify the bridge deck personnel to retract.

7. The installation method of a water supply and drainage pipeline under a bridge according to claim 6, wherein the specific content of the step 3 is as follows:

Step 3.1, install a gantry on the brackets at the front and rear of the pipeline to be installed, hang a chain hoist at the midpoint of the gantry, and tie the hoist to the steel pipe;

Step 3.2, using the lever principle, pull up the front and rear ends of the steel pipe with a hand hoist, and then place the pipe bracket with the pipe hoop above the bracket. 8 pipe supports, after the steel pipe is positioned and welded, the pipe supports are welded firmly and treated with anti-corrosion;

Step 3.3, after the steel pipe is in place, an additional chain hoist is installed at the front end of the steel pipe to adjust the axial displacement of the steel pipe, so that the steel pipe can be welded with the steel pipe installed in front;

Step 3.4: After the pipe hoisting and welding work is completed, transfer all the construction equipment and tool materials on the cantilever working platform to the bridge deck, evacuate all the construction personnel on the cantilever working platform to the bridge deck, and move the counterweight cart to work the cantilever. The platform moves to the next work section and repeats the above steps.

8. The installation method of a water supply and drainage pipeline under a bridge according to claim 7, wherein the specific content of the step 3.3 is as follows:

The surface of the steel pipe is wrapped with hessian tape to protect the surface coating of the pipe, and then the nylon fiber sling is wound in multiple turns and tightly wound in the middle of the sack tape. Adjust the length of the sling to adjust the axial spacing of the end-to-end connection of the pipeline. When the precision of the counterpart meets the specified requirements, immediately use electric welding to weld multiple points on the circumferential weld to fix the end of the pipeline. There are no less than 3 welding points and spot welding. The length is 80 mm to 100 mm, the spot welding spacing is not more than 400 mm, and the height of the welding seam is 2 mm to 4 mm.

9. The installation method of a water supply and drainage pipeline under a bridge according to claim 8, wherein the specific content of the step 4 is as follows:

The expansion joint shall be inspected before installation; the expansion joint shall be connected with the steel pipe by flange, the flange shall be kept concentric with the pipe, and the two flanges shall be kept parallel, and the first to second adjacent sides of the flange interface shall be welded. The interface can be welded after the flange bolts are fastened; the water supply and drainage pipes composed of steel pipes are respectively installed with an expansion joint at both ends and the middle.