I) Water supply project
1. Installation quality assurance measures: Installation preparation: Be familiar with drawings carefully before installation, and determine the construction method and technical disclosure tools according to the construction plan.
Physical measures to prepare. Consult relevant professional equipment drawings and decoration building drawings, and check whether the coordinates and elevations of various pipelines intersect and whether the space used for pipeline layout is reasonable. If there is any problem, discuss and solve it with relevant designers in time, and make a record of change negotiation.
Prefabrication:
According to the design drawings, draw the construction sketch of pipeline diversion, pipe diameter, diameter change, reserved nozzle and valve position, mark the actual installation structure position, measure the actual installation accurate size according to the marks, record it on the construction sketch, and then prefabricate it according to the size measured in the sketch.
Installation of main pipeline: Before installation of main pipeline, clean the pipe wall and joint with emery cloth, and the joint gap shall not be less than 2mm. After leveling and straightening, fix the pipe and support the pipe at the corner and the beginning to prevent axial movement. All nozzles should be blocked at any time.
Open installation of risers: hanging lines are installed from top to bottom on each floor, and prefabricated risers are arranged in layers according to numbers.
Install in sequence, align the marks when straightening, and check whether the height and direction of the reserved slings are correct. The outlet of branch pipe should be temporarily blocked, and the installation of riser valve should be convenient for operation and maintenance. After the installation, use wire to hang straight and align, and cooperate with civil engineering to block the floor holes.
Concealed installation of riser: it is advisable to set section steel at the riser wellhead in the shaft, and install fixtures by hanging wires from top to bottom.
The riser installed in the wall shall be provided with pipe grooves in the structural construction. After the riser is installed, it should be hung straight for alignment and fixed with clips. The outlet of the branch pipe should be exposed and temporarily blocked.
Exposed installation of branch pipes: install prefabricated branch pipes one by one from the outlet of branch pipes, and remove flanges when there are valves.
Before installation, temporary fixing cards shall be appropriately added according to the length of the pipeline. After leveling and alignment, branch cards shall be installed, temporary fixing cards shall be removed and temporarily blocked. If the water supply branch pipe is equipped with a water meter, the connecting pipe should be installed first. After the pressure test, the connecting pipe should be removed and the water meter installed before the project is completed.
Concealed installation of branch pipe: after determining the height of branch pipe, draw lines to locate it, remove the pipe groove, apply prefabricated branch pipe in the groove, level and locate it, and then fix it with hook nails. The reserved opening for hot and cold water of sanitary ware should be open and sealed.
Pipeline pressure test:
Laying, concealed installation and heat preservation of water supply pipeline should be tested by single hydraulic pressure before concealment. After the pipeline system is installed, a comprehensive water pressure test should be carried out. During the hydrostatic test, air is released, filled with water, and then pressurized. When the pressure rises to the specified requirements, stop pressurizing and check. If there is no leakage in all interfaces and valves, observe that the pressure drop is within the allowable range, notify relevant personnel for acceptance and handle handover procedures. Then drain the water, and the galvanized layer of the damaged bracket or pipeline should be treated with anti-corrosion treatment, and then concealed works should be carried out.
Anti-corrosion and heat preservation of pipelines: The laying and installation of water supply pipelines should be carried out in accordance with the design requirements and national acceptance specifications, and all the damaged parts of galvanized coatings of supports and pipelines should be painted with antirust paint. The insulation material and thickness of water supply pipeline meet the design requirements, and the quality reaches the national acceptance standard.
2) Drainage works
1. Installation quality assurance measures: prefabrication: measure the size according to the drawing requirements and the actual situation, and draw the processing sketch according to the position of the reserved hole. Measure the pipe size according to the sketch and disconnect the pipe. The fracture surface should be smooth, and the flying thorns inside and outside the fracture surface should be removed with a milling cutter or scraper, and the outer edge should be milled to 15. Horn. Before bonding, the socket should be inserted for testing, but not all, which is generally 3/4 of the depth of the socket. After the trial insertion is qualified, wipe the moisture and dust of the socket to be bonded with cotton cloth. If there is oil stain, remove it with acetone. Apply adhesive with a brush, first coat the socket and then the socket, and then insert it vertically with force. When inserting glue, gently rotate the socket to facilitate the uniform distribution of glue, and it can be firmly bonded in about 30 seconds to 1 minute. Wipe off the spilled adhesive immediately after bonding. Pay attention to the reserved port direction when multi-port binding.
Supervisor installation: firstly, according to the coordinates and elevation required by the design drawings, a groove or embedded casing is reserved.
When buried underground, excavation and compaction shall be carried out according to the design coordinates, elevation, slope direction and gradient. Adopt supporting crane
During pipeline installation, supports and hangers shall be prepared according to design coordinates, elevation and slope direction. When the construction conditions are met, the prefabricated pipe sections will be transported to the installation site according to the number for installation. The bonding of each pipe section must also be carried out in sequence according to the bonding process. After all bonding, the pipeline shall be straight, with even slope and accurate reserved port position. Expansion joints are needed to install risers, and the upper edge of expansion joints is 70 ~ 100 mm away from the floor or toilet table. After the installation of the main pipe, the water closing test should be done, and the water outlet should be closed with an inflatable rubber plug to ensure no water leakage and the water level will not drop to the qualified level. The buried pipeline shall be backfilled with fine sand to the tube epithelium of 100mm, and covered with sieve soil. The pipeline shall not be damaged during compaction. After the hanging pipe is glued firmly, find the slope according to the direction of water flow. Finally, seal the reserved opening and block the hole.
Installation of riser: firstly, according to the design coordinate requirements, the holes should be reserved or removed, and the size of the holes should not be too large, and the stressed steel bars should not be damaged. Clean up the site before installation, and build an operation platform as needed. Transport the prefabricated riser to the installation site. First, clean the reserved expansion joint, unscrew the lock nut, take out the U-shaped rubber ring and clean up the sundries. Check whether the upper hole is suitable. The insertion end of the riser should be marked with the insertion length, then coated with soap solution, and fitted with a locking nut and a U-shaped rubber ring. When installing, first put the upper end of the riser into the upper hole and insert it vertically until it is marked (generally, the reserved expansion amount is
20 ~ 30mm). When appropriate, self-made U-shaped steel is fastened on the upper edge of expansion joint. Then find the alignment and measure whether the roof tee center meets the requirements. After correct, the hole can be blocked and the upper reserved expansion joint closed.
Branch pipe installation: firstly, remove the elevator hole or re-check whether the embedded parts are suitable. Clean up the site and build an operation platform as needed. Transport the prefabricated branch pipes to the site according to the number. Remove dust and moisture from all bonded parts. Lift the branch pipe horizontally, apply adhesive, and push it into the reserved nozzle. Adjust the slope according to the length of the pipe segment. When appropriate, fix the clamping frame and close all reserved nozzles and holes.
Installation of appliance connecting pipe: check the practice and thickness of building floor and wall. Find out the coordinates and elevation of the reserved hole. Then trim the reserved holes according to the exact size. The measured dimensions of different parts shall be recorded, prefabricated and numbered. When installing and bonding, the reserved nozzle must be cleaned before bonding. After cementing, align and straighten, close the nozzle and plug the hole. Open the cleaning port of the next riser, close the upper part with inflatable rubber plug, and carry out water closing test. After passing the test, remove the rubber plug and seal the cleaning port.
Closed water test: after the installation of drainage pipeline. The closed water test must be carried out according to the specified requirements. All concealed and concealed pipelines must be tested by sub-procedures: after the installation of sanitary ware and water supply system equipment is completed, the water test must be carried out;
Before testing the water, a test plan should be put forward, and at the same time, there should be enough water in the pool. And should be carried out before the last painting process.
2, water supply and drainage engineering quality common fault prevention measures, pipeline through the floor casing buried does not meet the specification requirements. Countermeasures: Make the following requirements for the casing of the pipeline crossing the floor: the casing of the pipeline must be steel casing with waterproof wing ring; The gap between casing and pipeline must be plugged with asphalt and filled with waterproof ointment; The installation of pipeline casing must also meet the relevant requirements of the Measures for the Treatment of Common Quality Defects in Guangzhou Construction Engineering.
The distance control between the drainage riser and the wall does not meet the requirements. Countermeasures: when making technical disclosure to the team, it is clearly stipulated that the distance between the riser and the wall finish surface is greater than or equal to 20mm；; The pipe clamp is set in strict accordance with the specification requirements, and the process is reasonable; It is required that the civil works must be straight and the decoration (painting) should be in place when the pipe back wall swings. When painting the pipeline, the wall surface must be protected, and the wall surface shall not be polluted.
Roof rainwater drainage floor drain installation is not in harmony with civil engineering, which affects roof drainage. Countermeasures: When the rainwater pipeline crosses the ceiling floor, it must be sealed with waterproof ointment. Require heaven and earth
The gradient of inclined running water should meet the requirements of the specification. The rainwater drainage floor drain should also meet the relevant requirements of Guangdong Province's Measures for the Treatment of Common Quality Defects in Building Engineering.
The pipeline laying on the roof, floor and expansion joints does not meet the requirements. Countermeasures: It is forbidden to lay along the ground without supports (piers), and steel supports (brackets) should be fixed with expansion bolts.
Laying method of frame. Support installation damage structure and waterproof layer, must be waterproof. pipeline
Appropriate compensation devices (such as expansion joints and expansion bends). ) must be installed when passing through expansion joints. The laying of pipes on the roof and floor should also comply with the relevant provisions of the Measures for the Treatment of Common Quality Defects in Construction Projects in Guangdong Province.
The slope and direction of drainage pipeline do not meet the requirements of design and construction specifications. Countermeasures: First of all, we should do a good job in the intersection of drawings, do a good job in the cooperation of various professions, so that there is pressure without pressure;
Arrange the construction according to the principle that small pipes give way to large pipes. According to the design requirements, identify the direction of water flow and determine the correct slope direction. According to the slope required by design and specification, pay off the support and hanger with horizontal datum points to ensure that the slope requirements are met.
The verticality and levelness of drainage pipes do not meet the requirements. Countermeasures: check whether the pipeline is straight before installation, and if it does not meet the requirements, it should be straightened or replaced;
Check whether the accessories meet the requirements, and do not install those that do not meet the requirements; Before pipeline installation, pay-off inspection shall be carried out to ensure the levelness and verticality of supports and hangers;
The setting and elevation of drain pipe inspection port and vent pipe do not meet the specification requirements. Countermeasures: Technical disclosure must be made before construction; Site elevation lines must be confirmed before construction;
Set inspection ports or ventilation pipes in strict accordance with the elevation required by the design and specifications; The bracket configuration is unreasonable, and the hole is opened by welding. Countermeasures: Configure supports and hangers in strict accordance with the support spacing and specifications required by the design and specifications; Support holes must be drilled and anchored, and wind and electric welding are strictly prohibited; There is no groove when welding pipes with d=4mm or more.
Countermeasures: When the pipe wall thickness δ≥4mm is welded, the groove must be opened. Strengthen construction management, and timely correct the groove and welding that are not carried out as required.
The exposed part of the hemp root, plastic king or silk tooth of the threaded pipe shall not be treated with anti-corrosion. Countermeasures: after the connection of threaded pipes is completed, the exposed hemp roots or other fillers should be cleaned up, and the exposed parts of threaded teeth should be treated with anti-corrosion;
The outlet of the toilet seat is staggered from the sewage pipe, resulting in poor water outlet. Countermeasures: Before installation, we must cooperate with the decoration unit and the civil engineering unit to determine the installation position (thickness of tiles) of sewage pipes and sanitary ware. If the pin position of the sewage pipe is found, it should be reworked. The installation height of floor drain is too high, resulting in ground water accumulation.
Countermeasures: Make clear the floor height (finish) before installation, and rework if it exceeds the height;
3) Electrical engineering
1. The model and specification of the conduit and its accessories must meet the design requirements, and the outer wall of the conduit should be provided with continuous flame retardant signs and manufacturer's labels, with the spacing not greater than1m.. The nozzle of the line pipe should be flat and smooth; The connection between pipes and boxes (boxes) shall be firm and sealed. The height difference of boxes at the same elevation shall not be greater than 5mm, and the height difference of boxes installed in parallel shall not be greater than 1mm, and the boxes shall be firmly fixed.
The bending radius of the conduit should not be greater than 6D(D is the outer diameter of the conduit), and there should be no flattening and cracks during bending. Do a good job of marking and protective measures, and take protective measures when the pipeline passes through places that are vulnerable to mechanical damage.
2. The cut-off opening for laying galvanized wire tubes should be smooth, smooth and burr-free, and there should be no flattening, sag and crack at the bend, and the bending radius should not be less than 6 times of the outer diameter of the tube; Galvanized conduit shall be connected by thread, the length of thread shall not be less than half of the length of pipe joint, and the thread surface shall be smooth;
When laying, the arrangement of conduits should be neat/beautiful, and the allowable error is: not more than 3mm every 2m, and the total length should not exceed1/2 of the inner diameter of conduits;
When the conduit is laid on the wall and enters the holes of junction boxes such as switches and sockets, the conduit should be properly bent into a double bend (duck neck bend), and the conduit should not be inclined to penetrate into the junction box. At the same time, the conduit should be close to the building and fixed at a distance of 30mm from the junction box. Where there is an elbow joint, both sides of the elbow joint should also be fixed. All interfaces between conduit and conduit, conduit and junction box/electric box shall be bridged by special grounding wire clips, and the cross section of copper wire for bridging shall not be less than 2mm.
3. The specifications and models of the wires for the pipe threading shall be consistent with the design drawings. There is no joint for the wires in the pipe, and the joint is located in the junction box. Wires with different voltage levels and different circuits should not be worn in the same tube. Do a good job of finished product protection, and seal the thread end with a box cover or iron sheet after construction.
After completion, the insulation resistance of each loop shall be tested, and the insulation resistance of each loop shall be greater than 0.5MΩ.
4, switch, socket, lamps and lanterns, distribution box installed in the same building at the same elevation, switch, socket installation height should be consistent, the error is not more than 5mm, the elevation difference of parallel installation should not be greater than 65438+/-0 mm .. The cover plate of concealed switch and socket should be close to the wall, leaving no gaps. When installing the switch socket, the wiring should be correct, the live wire should enter the switch, and the on-off position of the switch should be consistent.
The left hole of single-phase three hole socket is the neutral end and the right hole is the phase end. The base of lamps and lanterns should be close to the floor, the deviation of the center line of lamps and lanterns installed in rows should not be greater than 3mm, and the metal shell of all lamps and lanterns should be well grounded. The box cover of the distribution box should be flat and close to the disk, the wires in the box should be arranged neatly and beautifully, the wiring should be correct and firm, the terminal numbers should be complete, and the wiring diagram should be complete.
5. The metal frame of distribution box, distribution box and cabinet shall be neat and free from deformation, the foundation steel shall be reliably grounded, and the paint shall be complete and uniform; Gas welding and electric welding holes shall not be used on panels and cabinets, and shall not be welded with foundation steel;
Drawer-type or hand-push distribution cabinet drawers should be flexible and light, without jamming and collision; Contact center line should be consistent, close contact; Mechanical interlocking or electrical interlocking action should be correct and reliable; Grounding contact should be well grounded;
The model and specification of the electrical equipment in the panel and cabinet shall meet the design requirements, with complete accessories, neat arrangement, reliable fixation, good electrical contact, correct signal device circuit display and reliable operation;
The secondary wiring in the cabinet should be correct, the connection should be firm and reliable, the direction should be reasonable, the wiring should be neat and beautiful, the wire insulation should be good, there is no connector in the cabinet, and the loop number is correct and clear;
The color code of the bus bar in the cabinet shall be uniform and complete, the grounding (zero) section shall be selected correctly, and the parts to be protected from corrosion shall be painted evenly without omission.
6. The main quality common faults of electrical engineering and possible quality common faults and preventive measures. Incorrect wiring of socket and nut, misadjustment or missing connection. Countermeasures:
Clarify the disclosure team and ask the socket to be connected left and right. All grounding wires shall be connected at the designated position, and zero wire shall not be used instead of grounding wire. After the construction is completed, the special test socket shall be used for testing, and the wiring shall not be loose or virtual.
The installation elevation of high and low switches and sockets in the same room is inconsistent, and the deviation exceeds the specification requirements; Switches and sockets installed in parallel are not flush, and the deviation is too large.
Countermeasures: Contact the decoration and civil engineering majors in time, and determine the decoration elevation baseline of each place in writing. When installing conduits and boxes, the electrician team must find the level with a spirit level and a horizontal connector, and ensure that the installation elevation of switches or sockets of the same type is consistent.
Metal shells of lamps and other electrical appliances with installation elevation below 2.4m are not grounded or reliably protected.
Countermeasures:
When ordering metal lamps and other electrical appliances with installation elevation lower than 2.4m, the supplier shall indicate the grounding point on the lamp shell and have a clear general grounding symbol. During the construction of this loop, the team particularly emphasized the laying of grounding wire, and the lamp shell must be grounded according to the specification requirements when installing lamps.
The distribution box, panel, cabinet and the second-floor metal plate among them are not reliably grounded. Distribution boxes, panels and cabinets are equipped with doors or panels that can be electrically opened. Bare copper flexible wires with appropriate sections are not used to cross the boxes, panels and cabinets, or ordinary single copper wires are used.
Countermeasures: When ordering distribution boxes, panels and cabinets, it should be clearly required at the bottom of the cabinet or (other suitable locations).
Set up a special grounding plate, the grounding should be firm and reliable, and the grounding points of each loop should be connected with the grounding plate respectively. The openable door or panel of the cabinet should be connected with the distribution box, panel and cabinet with bare copper wire of appropriate cross section, and the grounding jumper should be made.
The selection of air and leakage switches for trunk lines and branch lines is incorrect or unreasonable, and the product quality is reliable. Countermeasures: Construction personnel must carefully review the construction drawings and check and accept the air switches, leakage switches and configuration cables of distribution trunk lines and branches. Strive to meet the distribution requirements in the configuration of trunk and branch lines, and the operating current level of leakage switch is correct and reasonable.
When the conduit is connected with the trunking (box), tray and cabinet, the opening shall be welded, and there is no forced female thread inside and outside, and the thread at the pipe end is exposed too much, and there is no plastic sheath nozzle at the pipe end.
Countermeasures: When the conduit is connected with the box, tray and cabinet, it must be arranged as a whole according to the number of loops, and a hole opener should be adopted.
Holes should be made, which should be arranged neatly and at reasonable intervals. Burrs should be cleaned up in time after the holes are made. When the conduit is connected with the trough, box, board, cabinet, etc. , it must be fastened inside and outside with a booster matched with the wire tube, and it must be protected with a plastic mouth protector matched with the pipe diameter when passing through the tube.
There are no junction boxes for wall lamps, ceiling lamps, chandeliers and other electrical appliances. Countermeasures: Strengthen the monitoring and management of the shift, and resolutely put an end to the phenomenon that when wall lamps, ceiling lamps and chandeliers are installed, the terminals of lamps are directly connected to the equipment without setting a junction box. Jumpers of conduits and boxes are not connected by special grounding clamps and fusion welding according to the current specifications, or jumpers are improperly selected. Countermeasures: In view of this common fault, we should first control it when purchasing, and the special grounding wire cards of various specifications must match the wiring pipes. When receiving the goods at the site, you should check them carefully. Grounding jumper and electrical conduit are made of copper wire with a cross section of 4 square millimeters, and it is forbidden to use fusion welding to make jumper.
The conduit laying arrangement is not neat and beautiful, the hanger and clip code setting is unreasonable, the distance between the fixed points is uneven, and the distance between the pipe clip and the terminal, the midpoint of the elbow, the edge of the electrical appliance or (box, plate and cabinet) exceeds 500mm.
Countermeasures: During the construction of electric conduit, all loops must be arranged as a whole, and the specific operations must be arranged neatly, horizontally and vertically. The supports, hangers and clips should be arranged reasonably, neatly and beautifully, and the fixed points should be evenly spaced, which meets the requirements of the specification.
The laying length of metal hose and its connection with lamps and lanterns do not meet the requirements. Countermeasures:
The laying length of metal hose is strictly controlled within the specification requirements.
B metal hoses shall not be directly buried in the ground or concrete, nor shall they be installed in damp places. C there should be no joint in the middle of the metal hose.
D when metal hoses are connected to junction boxes and equipment, they must be fastened with hose joints.
4) Lightning protection and grounding installation project
(1) The lightning protection welders in this project must be trained and qualified welders with certificates.
(2) Round iron should be welded on both sides, with the weld length not less than 6d and flat iron welding length not less than 50mm, with at least three sides welded.
(3) The flux of the weld should be removed. Welding water should penetrate evenly, but should not bite the steel bar.
(4) The corner of the lightning protection belt should not be at right angles, and the radius should not be less than 10d. Eleven, take cover engineering quality assurance measures
1, strictly implement the construction specification for concealed works.
2. Strengthen the test and inspection of steel to ensure the quality of raw materials, semi-finished products, finished products and processes.
3, strengthen the concealed engineering quality inspection, implement the team self-inspection, mutual inspection, handover inspection "three inspection" system.
4, steel bar alignment, prevent steel binding deflection or skeleton distortion.
5. When lifting the steel skeleton, in order to prevent the steel skeleton from lifting deformation, the lifting operation should be as smooth as possible, and the skeleton with poor stiffness can be reinforced with wooden poles.
6, mortar pad is reliable, the erection of steel can use the pad buried with iron wire, tied to the outside of the steel skeleton, at the same time, in order to make the protective layer thickness accurate, the application of iron wire to pull the steel skeleton to the template, and squeeze the pad.
7, steel bar connection by welding, set on the same component welding joints must be staggered, a steel bar can not have two joints. The cross-sectional area of steel bars with joints accounts for 50% of the total cross-sectional area of steel bars.
8, steel bar connection using binding, joint position must be staggered. The percentage of the sectional area of steel bars with joints to the total sectional area of steel bars: the tensile area should not exceed 25%, and the compressive area should not exceed 50%. Twelve, embedded parts, reserved hole guarantee measures
1, when making embedded parts, welding shall be carried out according to relevant regulations.
2. In order to prevent the displacement of embedded parts, the embedded parts are fixed around with nails after being placed in the design position.
3. Carefully check the drawings of embedded parts. If it is found that the anchorage of the embedded parts collides with the skeleton reinforcement, the position and practice of the anchorage reinforcement can be appropriately changed to make the embedded parts smoothly installed into the mold.
4, vibrating concrete, don't make the vibrator will be embedded parts vibration slanting, should be designated persons after the vibrating, embedded parts arranged.
5, in order to strengthen the stability of the reserved hole template, reserved hole in the middle of the horizontal support shall not be less than three.
If you want to know more about the construction information such as "Preventive Measures for Common Quality Problems in the Installation of Student Apartments", you can search in Zhong Da Consulting Building.
For more information about project/service/procurement bidding, and to improve the winning rate, please click on the bottom of official website Customer Service for free consultation:/#/? source=bdzd