CN113374935A - Construction method for underwater installation of water intake head of water plant by using ship-borne method - Google Patents
Construction method for underwater installation of water intake head of water plant by using ship-borne method Download PDFInfo
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- CN113374935A CN113374935A CN202110644552.6A CN202110644552A CN113374935A CN 113374935 A CN113374935 A CN 113374935A CN 202110644552 A CN202110644552 A CN 202110644552A CN 113374935 A CN113374935 A CN 113374935A
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
- F16L1/00—Laying or reclaiming pipes; Repairing or joining pipes on or under water
- F16L1/12—Laying or reclaiming pipes on or under water
- F16L1/14—Laying or reclaiming pipes on or under water between the surface and the bottom
-
- E—FIXED CONSTRUCTIONS
- E03—WATER SUPPLY; SEWERAGE
- E03B—INSTALLATIONS OR METHODS FOR OBTAINING, COLLECTING, OR DISTRIBUTING WATER
- E03B3/00—Methods or installations for obtaining or collecting drinking water or tap water
- E03B3/04—Methods or installations for obtaining or collecting drinking water or tap water from surface water
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- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Environmental & Geological Engineering (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Hydrology & Water Resources (AREA)
- Public Health (AREA)
- Water Supply & Treatment (AREA)
- Earth Drilling (AREA)
Abstract
The invention discloses a construction method for mounting the head of a water intake of a water plant underwater by a ship-hanging method, which comprises the following steps: firstly, moving a water intake head part to a floating crane hoisting position through a truck crane on a crane ship; hoisting the water taking head component from the shore platform by using a floating crane respectively, and then transporting the water taking head component to an overwater installation point by using the crane ship so as to carry out next underwater installation; and thirdly, sinking the single piece of the water gap head to an underwater installation point through the crane ship, and installing a water taking head by a diver underwater. The construction method for underwater installation of the water intake head of the water plant by the ship-hanging method has the advantages of low construction difficulty and high installation efficiency.
Description
Technical Field
The invention relates to installation of a water intake head of a water plant, in particular to a construction method for installing the water intake head of the water plant underwater by a ship-hanging method.
Background
Water plants near rivers generally take water from the rivers, and water taking port heads need to be paved at the water taking section. As the water intaking head engineering: adopting a phi 800mm steel pipe pile underwater overhead structure, forming a longitudinal and transverse rectangular layout by 24 steel pipe piles, combining the longitudinal and transverse beams into an integral platform, installing two water taking head parts at the upper part, totally 10 bell-mouthed grids for water inlet, laying 2 parallel steel pipe piles by adopting a gravity flow water conduit DN2000mm, and extending the steel pipe piles to a pump room; and the water taking head component is a second component, the weight of each component is 47 tons, and the components are respectively manufactured and assembled on a shore platform.
The existing water intake head is generally installed on land in a crane mode, and earth excavation is needed before installation, so that the water intake head installation mode of the water plant has the defects of large engineering quantity and low installation efficiency.
Disclosure of Invention
The invention aims to provide a construction method for mounting the head of the water intake of a water plant underwater by a ship-hanging method, which has the advantages of low construction difficulty and high mounting efficiency.
In order to achieve the above object, the present invention provides a construction method for installing the head of a water intake of a water plant underwater by a ship-lift method, the construction method comprising:
firstly, moving a water intake head part to a floating crane hoisting position through a truck crane on a crane ship;
hoisting the water taking head component from the shore platform by using a floating crane respectively, and then transporting the water taking head component to an overwater installation point by using the crane ship so as to carry out next underwater installation;
and thirdly, sinking the single piece of the water gap head to an underwater installation point through the crane ship, and installing a water taking head by a diver underwater.
Preferably, the hoisting load of the truck crane is 100-150 t.
Preferably, before the step one, the construction method further comprises: four lifting points on a single piece of the nozzle head are checked.
Preferably, before the step one, the construction method further comprises: and checking the hoisting and amplitude-changing equipment on the hoisting vessel.
Preferably, step three comprises: the floating crane runs to a designated position, then anchoring and positioning are carried out, then measurement is carried out, fine adjustment and accurate positioning are carried out by using an anchor rope, the water inlet depth of the single piece at the head part of the water intake is determined according to real-time water level and water flow velocity, when the single piece at the head part of the water intake is close to a position, all-around inspection is carried out, the single piece is accurately positioned according to the requirement of a design drawing, a 3-position butt joint mark is welded on an onshore flange in advance, the flange is installed by adopting a 3-point type positioning method underwater, after all connection is completed, the hook is loosened, and the floating crane is removed.
Preferably, step three comprises: firstly, trial hoisting 20% of load by the crane ship, and adjusting the hoisting steel wire rope and the crane ship direction; secondly, slowly lifting 100% of load until the water intake head single piece is 20cm away from the ground, suspending, fully checking the operation of the crane ship and the mechanical equipment again until the normal operation is confirmed, and finally continuously lifting the water intake head single piece to move to the water surface, and then lifting the water intake head to the water surface; then, under the guidance of a measurement technician, the single piece of the water intake head is hung to a specified installation water area for positioning, the water intake head is hung to a position which is 1 meter away from the platform underwater according to the water level and the elevation, a diver is arranged to launch, the diver cooperatively commands the installation direction of the single piece of the water intake head, after the direction of the single piece of the water intake head is aligned, the single piece of the water intake head is slowly hung to the underwater platform, the diver is arranged to primarily fix the single piece of the water intake head underwater, the diver removes a hoisting steel wire rope and a lifting appliance underwater, the diver continuously reinforces the single piece of the water intake head underwater until the technical requirement of a design specification is met, and then a group of divers is arranged to perform comprehensive inspection and perfect, and the underwater photography and acceptance are arranged.
Preferably, in step three, the number of people launching each diver is at least two or more; the single-group diving operation consists of four persons, and the double-group diving operation consists of seven to eight persons.
Preferably, in step three, the preliminary fixing is performed by using bolts.
Preferably, in step three, the determination of the underwater height takes relative elevation control.
Compared with the prior art, the method has at least the following advantages:
1. the method of the boat crane can be used for rapidly carrying and positioning the head of the water intake, the positioning accuracy is high, and the carrying cost is low;
2. after the head of the water intake is transported to the designated position by a ship, the water intake can be quickly installed under the cooperation of divers, and the installation efficiency is high.
Additional features and advantages of the invention will be set forth in the detailed description which follows.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:
FIG. 1 is a schematic view of a lifting and hanging of a water intake head in a construction method for underwater installation of the water intake head of a water plant by using a boat crane method provided by the invention;
fig. 2 is a schematic structural view of a single piece of the water intake head of fig. 1.
Description of the reference numerals
1. Crane vessel 2 and truck crane
3. Goods yard 4, water intake head single piece
5. A bell mouth 6 and a hanging point.
Detailed Description
The following detailed description of embodiments of the invention refers to the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the invention, are intended for purposes of illustration and explanation only and are not intended to limit the scope of the invention.
In the present invention, unless otherwise specified, the directional words "upper, lower" and the like included in the terms merely represent the orientation of the terms in the conventional use state or are colloquially known by those skilled in the art, and should not be construed as limiting the terms.
The invention provides a construction method for mounting the head of a water intake of a water plant underwater by a ship-hanging method, which comprises the following steps:
firstly, moving a water intake head part to a floating crane hoisting position through a truck crane on a crane ship;
hoisting the water taking head component from the shore platform by using a floating crane respectively, and then transporting the water taking head component to an overwater installation point by using the crane ship so as to carry out next underwater installation;
and thirdly, sinking the single piece of the water gap head to an underwater installation point through the crane ship, and installing a water taking head by a diver underwater.
In the present invention, the hoisting load of the truck crane can be selected within a wide range, but in order to further improve the weighing strength, it is preferable that the hoisting load of the truck crane is 100-.
In the present invention, in order to further improve the safety of hoisting, preferably, before the step one, the construction method further includes: four lifting points on a single piece of the nozzle head are checked.
In the present invention, in order to further improve the safety of hoisting, preferably, before the step one, the construction method further includes: and checking the hoisting and amplitude-changing equipment on the hoisting ship.
In step three of the present invention, in order to ensure the accuracy of installation and the sealing performance of installation, preferably, step three includes: the floating crane runs to a designated position, then anchoring and positioning are carried out, re-measurement is carried out, fine adjustment and accurate positioning are carried out by using an anchor rope, the water inlet depth of the water intake head single piece is determined according to real-time water level and water flow velocity, when the water intake head single piece is close to a position, all-around inspection is carried out, the water intake head single piece is accurately positioned according to the requirement of a design drawing, a 3-position butt joint mark is welded on an onshore flange in advance, the flange is installed by adopting a 3-point type positioning method underwater, after all connection is finished, the hook is released, and the floating crane is removed.
On the basis of the above embodiment, in order to further improve the mounting accuracy, preferably, the third step includes: firstly, trial hoisting 20% of load by the crane ship, and adjusting the hoisting steel wire rope and the crane ship direction; secondly, slowly hoisting 100% of load until the single piece of the head part of the water intake is 20cm away from the ground, suspending, fully checking the operation of the crane ship and the mechanical equipment again until the normal operation is confirmed, most continuously hoisting the single piece of the head part of the water intake to move to the water surface, and then hoisting the head part of the water intake to the water surface; then, under the guidance of a measurement technician, the single piece of the head of the water intake is hung to a specified installation water area for positioning, the head of the water intake is hung to a position which is 1 meter away from a platform underwater according to water level and elevation, a diver is arranged to launch, the diver cooperatively indicates the installation direction of the single piece of the head of the water intake, after the direction of the single piece of the head of the water intake is aligned, the single piece of the head of the water intake is slowly hung on the platform underwater, the diver is arranged to primarily fix the single piece underwater, the diver removes a hoisting steel wire rope and a lifting appliance underwater, the diver continuously reinforces the single piece underwater until the technical requirement of a design specification is met, a group of divers is arranged to perform comprehensive inspection and perfection, and underwater photography and acceptance are arranged.
In the invention, the requirement on divers is higher, and in order to further improve the diving safety coefficient, preferably, in the third step, the number of people for diving each time is at least more than two; the single-group diving operation consists of four persons, and the double-group diving operation consists of seven to eight persons. Preferably, when two or more groups of diving operators work on a working surface, the diving operators need to check the respective air supply rubber pipes and signal ropes at any time to prevent mutual twisting; diving by a diver, holding the diving working ladder into water without directly jumping into the water, performing watertight inspection and communication equipment performance inspection on diving equipment on the water surface, and diving along a guide rope after the underwater equipment is qualified; when the body does not adapt to the pressure balance action in the submergence process, continuing submergence after the symptom disappears; and the water surface is informed in time after the operation point is reached.
In the above embodiment, in order to further facilitate the fixing, preferably, in step three, the preliminary fixing is fixed by using bolts.
Finally, in the present invention, the method for determining the underwater height is not particularly limited, but in order to improve the accuracy, it is preferable that the determination of the underwater height takes relative elevation control in step three.
The present invention is illustrated by the following examples.
Example 1
The embodiment adopts the method to carry out the installation construction of the water intake head of the water plant.
The water taking head installation project is positioned in the Yangtze river section of the New Port in Mingchang county of Tanchu lake, the distance from the offshore area in the dry season is about 45 meters, and water is taken from the river. The current water level is 4.0m, the embankment height is 6.5m from the existing embankment, and the embankment height is 10.5 m.
The crane ship is selected from Wanwu lake for 18#, the maximum hoisting weight is 120 tons, the hoisting capacity is 90 tons at a depression angle of 60 degrees, the amplitude is 12 meters, the capacity of hoisting the water head component is met, and the safety factor is 1.91.
A jack rope: this adopts four point to lift by crane the mode, and two, four, the shackle four of lifting jack rope, the horizontal contained angle 60 of lifting jack rope. Stress of a single steel wire rope: 4Fcos30 ° -47 (t), F ═ 13.57 (t); according to the technical specification of hoisting and hoisting safety in building construction JGJ276-2012 table 4.3.1, the strength of the pear-shaped ring with the steel wire rope phi 52.0mm is reduced by 25%. The breaking force of the lifting rope is 13.57 ÷ 0.75 × 10 ÷ 180.9t, and the new steel rope phi 52.0mm (6 × 37+1) with the strength grade of 1850Mpa is selected for the hoisting. The breaking tensile force is 185.t >180.9t, and the requirement is met;
and (4) shackle disassembly: more than four shackle specifications of DW phi 35(20 ton grade is more than 13.57 tons) are selected.
Lifting lugs: thickness h of the weldf8mm, the length of a single-side welding seam is 250mm, the lifting lug material Q235B is subjected to manual arc welding, and the tensile strength of the welding rod is 420 MPa.
σ＝N/lwhe＝13.57*1000*10/(0.250*2*0.008)＝67.85(Mpa)≤ft wWelding under 420MPa
The seam meets the requirements. Ear plate: t is 13.57 × 1000 × 10/(0.018 × 2 × 0.0655) ═ 57.5mpa, and the strength requirement of the Q235B otic placode is met. For safety, reinforcing ribs delta are additionally arranged at two ends of the ear plate16mm, satisfy the side direction atress of lug, increase its stability.
The underwater platform of the water intake is: 24m × 10m, platform elevation: 10m below, and 24 steel pipe piles are designed at the bottom as a foundation; 4-7 signal floating pumps are arranged around the construction water area.
The list of the crane ship, hoisting tools and auxiliary materials is shown in table 1, and the list of the crane installation engineering management, technology and technician configuration is shown in table 2.
TABLE 1
TABLE 2
| Serial number | Name/work kind | Number of | Post | |
| 1 | |
1 | Is responsible for | |
| 2 | |
1 | Executive long | |
| 3 | Hoisting team and group | 6 | Hoisting (si suo, signal worker) | |
| 4 | |
2 | Technique, |
|
| 5 | |
2 | Safety in the field | |
| 6 | |
4 | Boat engine operation | |
| 7 | |
4 | Underwater operation (Single diving scheme) | |
| 8 | Comprehensive team and |
4 | Comprehensive auxiliary work |
The preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, however, the present invention is not limited to the specific details of the above embodiments, and various simple modifications can be made to the technical solution of the present invention within the technical idea of the present invention, and these simple modifications are within the protective scope of the present invention.
It should be noted that, in the foregoing embodiments, various technical features described in the above embodiments may be combined in any suitable manner, and in order to avoid unnecessary repetition, various combinations that are possible in the present invention are not described separately.
In addition, any combination of the various embodiments of the present invention is also possible, and the same should be considered as the disclosure of the present invention as long as it does not depart from the spirit of the present invention.
Claims (9)
1. A construction method for mounting the head of a water intake of a water plant underwater by a ship-borne method is characterized by comprising the following steps:
firstly, moving a water intake head part to a floating crane hoisting position through a truck crane on a crane ship;
hoisting the water taking head component from the shore platform by using a floating crane respectively, and then transporting the water taking head component to an overwater installation point by using the crane ship so as to carry out next underwater installation;
and thirdly, sinking the single piece of the water gap head to an underwater installation point through the crane ship, and installing a water taking head by a diver underwater.
2. The construction method according to claim 1, wherein the hoisting load of the truck crane is 100-150 t.
3. The construction method according to claim 1, wherein before step one, the construction method further comprises: four lifting points on a single piece of the nozzle head are checked.
4. The construction method according to claim 1, wherein before step one, the construction method further comprises: and checking the hoisting and amplitude-changing equipment on the hoisting ship.
5. The construction method according to claim 1, wherein the third step comprises: the floating crane runs to a designated position, then anchoring and positioning are carried out, re-measurement is carried out, fine adjustment and accurate positioning are carried out by using an anchor rope, the water inlet depth of the water intake head single piece is determined according to real-time water level and water flow velocity, when the water intake head single piece is close to a position, all-around inspection is carried out, the water intake head single piece is accurately positioned according to the requirement of a design drawing, a 3-position butt joint mark is welded on an onshore flange in advance, the flange is installed by adopting a 3-point type positioning method underwater, after all connection is finished, the hook is released, and the floating crane is removed.
6. The construction method according to claim 5, wherein the third step comprises: firstly, trial hoisting 20% of load by the crane ship, and adjusting the hoisting steel wire rope and the crane ship direction; secondly, slowly hoisting 100% of load until the head of the water intake is suspended 20cm away from the ground, fully checking the operation of the crane ship and mechanical equipment again until the operation is normal, most continuously hoisting the head of the water intake to move to the water surface, and then hoisting the head of the water intake to the water surface; then, under the guidance of a measurement technician, the single piece of the water intake head is hung to a specified installation water area for positioning, the water intake head is hung to a position which is 1 meter away from the platform underwater according to the water level and the elevation, a diver is arranged to launch, the diver cooperatively commands the installation direction of the single piece of the water intake head, after the direction of the single piece of the water intake head is aligned, the single piece of the water intake head is slowly hung to the platform underwater, the diver is arranged to primarily fix the single piece underwater, the diver removes a hoisting steel wire rope and a lifting appliance underwater, the diver continuously reinforces the single piece underwater until the technical requirements of design specifications are met, and then a group of divers is arranged to fully check and accept underwater photography.
7. The construction method according to claim 5, wherein in step three, the number of divers launching water is at least two or more per time; the single-group diving operation consists of four persons, and the double-group diving operation consists of seven to eight persons.
8. The construction method according to claim 5, wherein in step three, the preliminary fixing is performed by bolt fixing.
9. The construction method according to claim 5, wherein in step three, the determination of the underwater height adopts relative elevation control.
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| CN202110644552.6A CN113374935A (en) | 2021-06-09 | 2021-06-09 | Construction method for underwater installation of water intake head of water plant by using ship-borne method |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114923032A (en) * | 2022-04-08 | 2022-08-19 | 淮安市水利勘测设计研究院有限公司 | Construction method for integral installation of large-diameter long-distance river-crossing pipeline |
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| CN114923032A (en) * | 2022-04-08 | 2022-08-19 | 淮安市水利勘测设计研究院有限公司 | Construction method for integral installation of large-diameter long-distance river-crossing pipeline |
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