Central air conditioning project is a systematic project. Including technology, equipment, design, management and many other specifications.
(a) the relevant national norms or standards of central air conditioning engineering
1, Code for Construction and Acceptance of Ventilation and Air Conditioning Engineering (GB50243-97)
2. Code for Construction and Acceptance of Industrial Pipeline Engineering GBJ50235-97
3. Code for Construction and Acceptance of Welding Engineering of Field Equipment and Industrial Pipes (GBJ50236-97)
4. Technical Specification for Temporary Electricity Safety in Construction Site JBJ46-88
5. Unified Standard for Quality Inspection and Evaluation of Construction and Installation Engineering GBJ300-88
6. Standard for Quality Inspection and Evaluation of Ventilation and Air Conditioning Engineering GBJ304-88
7. General Code for Construction and Acceptance of Mechanical Equipment Installation Engineering JBJ23-96
8. Code for Construction and Acceptance of Compressor, Fan and Pump Installation Engineering JBJ29-96 1
(2) Brief introduction of installation and construction scheme of central air conditioning project.
1, general equipment installation method
1. 1 Equipment installation preparation
A. Installation layout, installation drawings, foundation drawings, main component drawings and installation instructions of machinery and equipment;
B. Relevant professional technical specifications and installation technical requirements;
C. packing list of mechanical equipment;
D, prepare auxiliary materials needed for equipment installation;
1.2 equipment installation method
A. Inspection and acceptance of equipment foundation The quality requirements of the size and position of mechanical equipment foundation shall conform to the relevant provisions of Appendix 1 of JBJ23-96 General Specification for Construction and Acceptance of Mechanical Equipment Installation Engineering, and make records of foundation inspection and acceptance;
B, mechanical equipment unpacking check box number and quantity, check whether the outer packaging is damaged; Check whether the name, model and regulations of the equipment conform to the design; Check whether the inventory equipment is complete and whether the surface is damaged and corroded; Make records of unpacking inspection of equipment;
C, according to the construction drawing pay-off and related building axis or edge line, delimit the installation baseline;
D after the equipment is in place, the allowable deviation between the datum plane, line or point of equipment positioning and the plane position and elevation of installation datum line shall meet the requirements of relevant regulations;
E. Leveling According to the requirements of the equipment itself, a damping pad is generally placed under the base of the equipment that is easy to vibrate, and the thickness of the damping pad should be uniform. In general, the equipment is leveled by using a leveling device with its own legs or installing a shim. The test position of equipment leveling, when not specified in the technical documents of the equipment, should be selected below the working face of the equipment; A guide surface for supporting the sliding part; Protect the guide surface or shaft of rotating parts; In the structure with high machining accuracy, it should be selected in the adjustable part, and the distance between the two sides should not be greater than 6 meters;
F, heavy fixed equipment or vibrating equipment, need equipment foundation, foundation reserved anchor bolt hole, anchor bolt in the reserved hole should be vertical without tilt, and the distance from the hole wall should be greater than 15mm, and should not touch the bottom of the hole, surface oil stain and scale should be removed, bolt exposed nut, its exposed length is13 to 2/3 bolt diameter, and the threaded part should be coated with a small amount of grease. Before grouting, the foundation should be cleaned and compacted, and the inclination of the anchor bolts should not affect the installation accuracy of the equipment. Only when the concrete in the hole of the anchor bolt reaches more than 75% of the design strength can the anchor bolt be tightened.
G. Equipment cleaning Equipment cleaning with cleaning requirements shall comply with the requirements in the first section of Chapter V of JBJ23-96; It is forbidden to scrape and clean the equipment surface with sharp tools such as metal;
H. The air inlet pipe, air outlet pipe and other equipment with special requirements shall be supported separately and firmly connected with the foundation or other buildings; When the fan is connected to the air duct, it is not allowed to be forced against each other, and the casing should not bear the weight of other components.
1. Marking After the installation of each equipment is completed, the equipment tag number must be marked on the operation surface (the equipment tag number is consistent with the tag number in the equipment list, flow chart and equipment layout);
1.3 commissioning of equipment
A. Before the equipment is put into trial operation, the following conditions shall be met: equipment and its auxiliary equipment, pipelines, etc. The construction shall be complete, and the construction records and materials shall be complete. Among them: the flatness and geometric accuracy of the equipment have passed the inspection; Auxiliary equipment such as lubrication, cooling, water and electrical (instrument) control shall be inspected according to the system and meet the requirements of trial operation; The required testing instruments and safety protection devices meet the requirements of trial operation; The debugging organization has been implemented, and the personnel participating in the debugging should be familiar with the structure, performance and technical documents of the equipment, and master the operating procedures and debugging operations. The equipment and surrounding environment should be clean, and there should be no dust or noise operation near the equipment.
B, single equipment commissioning, empty load commissioning and load commissioning;
C, the requirements of trial operation should comply with the technical requirements of the equipment manufacturer or the relevant provisions of Chapter VII of JBJ23-96. Water, electricity, gas and gasoline required for trial operation can be delivered; All kinds of electrical instruments and lubricating devices are sensitive. When inching the equipment, there is no friction, jamming and abnormal sound; When the fan starts, turn down the air inlet, and gradually open the air inlet with the normal operation of the fan, and don't stay in the shock absorption area. When the equipment is running, stop immediately if there is any abnormality, and try again after troubleshooting. After a specified period of trial operation, the bearing temperature and lubricating oil temperature are normal, the equipment runs smoothly, the sound is normal, and other technical indicators meet the requirements of the technical documents of the equipment, which is regarded as qualified in the trial operation of the equipment.
2. Installation of air conditioning unit, fresh air unit and fan coil unit
2. 1 Equipment installation method (different from general equipment installation) When the unit is installed, the box should be clean and free of sundries, and the transportation should be timed. The hanger should handle it with care, and it is forbidden to bump. Hanger should be firm and correct. If there are embedded parts, the hanger can be welded on the embedded parts, and the thread of the hanger should be about 100mm, so as to prepare for adjusting the elevation. If there are no embedded parts, the hanger can be fixed with expansion bolts. When the air conditioning unit arrives in sections, the functional sections shall conform to the order and requirements specified in the design, the connections between functional sections shall be tight, and the waterway shall be smooth. The air leakage test results of field assembly units shall meet the requirements of specifications. Fan coil units should be tested by single-machine three-speed test run and water pressure test before installation, and can be installed only after passing the test. The support and hanger of the fan coil should be firm and reliable, and the installation position and height of the fan coil should be correct. The elastic connection between the supply return pipe and the fan coil should be tight; The connection between air duct and tuyere and fan coil unit should be tight and firm, and the air duct and fan coil unit should be soft connected to reduce vibration and noise.
3, pipeline installation
A, be familiar with the drawings carefully, understand the technological process, materials, specifications, connection modes and forms of supports and hangers of pipes, fittings and valves, understand the design intent in combination with the construction site, and define the technical requirements for installation.
B before construction, materials shall be inspected and tested, and unqualified products shall not be put into use. Welded pipes should be cleaned and derusted to reveal metallic luster, and then painted with red lead antirust paint twice. 100mm shall be reserved at both ends of the pipeline for welding. Welded pipes with wall thickness greater than or equal to 3 mm must be welded with V-groove. Weld width should be uniform, without slag inclusion, cracks, pores and other defects.
C, pipeline installation slope, broken direction should comply with the design requirements, cooling water supply pipe slope to the entrance and riser, cooling water return pipe slope to make water bend, condensate pipe broken direction to make water bend. The inclination of the pipeline can be adjusted by the suspender bolt or the pad between the bracket and the pipeline.
D, pipeline testing should be layered. Cooling water, water supply return pipe with test pressure of 0.8Mpa. The condensate pipe is only used for closed water test. Check the interface for leaks. The test results shall conform to the Code for Construction and Acceptance of Industrial Metal Piping Engineering (GB50235-97) and Code for Construction and Acceptance of Heating and Sanitary Engineering (GBJ242-82).
4. Wind control and safety
A, the production of air duct adopts electric shear bite machine, bending machine and other equipment. The bite seam of air duct must be tight, uniform in width and free from defects such as reaming and cracking. The longitudinal seam should be staggered. The appearance of air duct should be straight, with straight corners and equal end faces. The air duct and flange firmly meet the requirements. The air leakage per unit area of air duct should conform to the specifications.
B, flange welding should be firm, the size is correct, flange hole spacing should comply with the design requirements, screw holes should be interchangeable, using grinding wheel saw blanking, fixture counterpart, bench drill drilling.
C, duct hanger installation must pay-off, to ensure that the tuyere position is correct and beautiful.
5, heat preservation
5. 1 The pipe insulation material is soft polyurethane pipe shell, and the insulation pipe shell should be close to the outer wall, which requires that the inner diameter of the pipe shell should be accurate when ordering insulation materials. The joints and longitudinal joints of each shell shall be kept tight without longitudinal gap, and the insulation of the flange of the pipeline valve shall be convenient for separate disassembly and replacement. The insulation layer should leave enough space in this place. Generally, add 25-30mm to the bolt length, and then fill the gap with the same insulation chips. Bundle twice every 300-350 mm along the length of the pipeline. When the protective layer of glass fiber cloth is constructed, its lap width conforms to the specification, and the lap is even and elastic.
5.2 Ultra-fine glass wool board with aluminum foil should be used for duct insulation. Firstly, remove the dust from the air duct, and then stick the insulation nails coated with glue evenly on the surface of the air duct. Then, the ultra-fine glass wool board is attached to the surface of the air duct through nails, and the insulation layer is pressed by a pressing plate. Require neat assembly. Small pieces of insulation board should be placed on the upper part of the air duct, and all joints should be filled with fillers without gaps. Finally, the joint should be sealed with aluminum foil tape. See pipeline insulation for insulation practices at flanges.
Three, air conditioning system installation engineering control points
1, control point of sectional works
A, undertake the work of pipeline welding welder must hold relevant certificates;
B, weld internal appearance quality, quality must comply with the provisions of the specification;
C, pipe support must be made and installed according to standard drawings, and its fixing method and strength must meet the requirements of standard drawings.
D, the pipeline slope direction is correct, and the safety valve setting is reasonable;
E, pipeline and equipment outlet short pipe connection center line should be aligned, shall not be forced to connect. The setting of supports and hangers should be reasonable, and the equipment should not be subjected to external force of the pipeline.
2, duct and related air conditioning parts installation engineering quality control points
A, duct production must conform to the requirements of the specification;
B, duct installation orientation and elevation should be correct, duct and elevator contact is good and firm;
C, air conditioning system flange connection should be parallel, tight, even packing is not prominent, flange bolts should be prohibited to tighten, bolts in the same direction;
D, tuyere installation position elevation should be correct, more than three tuyere installation should be neat and coordinated, towards the same, tuyere arranged on the same axis, tuyere itself without deformation, no damage, flexible adjustment, and decoration surface seamless.
E, the air leakage of the system duct shall not be greater than the specification requirements;
3, insulation engineering quality control points
A, insulation layer should be flat and dense, uniform thickness, firm bonding without defects such as cracks, gaps, pay special attention to tee insulation quality;
B, insulation nails should be firmly bonded, not less than the specified number per square meter, and the arrangement distance should be uniform;
C, flange joint should be sealed with the same thermal insulation material as pipe fittings;
D, moistureproof layer all interface application aluminum foil tape seal, shall not burst or fall off;
E, protective layer construction should lap evenly and moderately.