Personnel
All personnel involved in the construction work (heavy lifters, welders, electricians) must be licensed and all construction personnel involved in the installation of pressure vessels should be familiar with this procedure and the relevant drawings and specifications.
Prerequisites
1. Technical data
The construction drawings are complete and the technical personnel in charge of the construction have made a drawing handover to the construction personnel; the construction personnel are familiar with the content of the construction drawings.
Construction personnel have been familiar with the content of the construction procedures.
Construction record forms are available.
The local special equipment safety supervision and management department is informed in writing before construction, and can be constructed after being informed.
2. Working environment requirements
The civil foundations have met the requirements and have been accepted as acceptable, foundation handover procedures have been carried out, underground works near the foundations have been completed and the site has been levelled and hardened.
Temporary roads for construction and transportation have been renovated to ensure smooth transportation.
Lighting and electrical equipment and materials for construction are complete to meet the construction requirements.
Lifting equipment for installation has arrived.
3. Construction preparation
Familiarisation with drawings and relevant information, mastering technical parameters of equipment and technical requirements for installation, and understanding environmental conditions for equipment installation.
Determining technical measures and construction methods according to construction procedures.
Safety technical briefing for construction personnel participating in pressure vessel installation to ensure that pressure vessel installation meets code requirements and construction safety.
Preparing various tools, machines and materials for installation according to the construction drawings and the construction technology plan.
Checking the equipment transport routes and construction sites should meet the equipment installation conditions before installation and construction according to the construction programme.
Foundation acceptance
intermediate handover certificates must be handled before the use of the pressure vessel foundation.
Foundation centre line, elevation and other markings are complete and clear, and the bolt length meets technical requirements.
Equipment unpacking acceptance
1. equipment in place before, should be timely for pressure vessel installation start-up notice, approved by the local technical quality supervision bureau informed, equipment unpacking acceptance by the construction unit organization, by the supervision, construction units to participate in the unpacking acceptance of equipment.
2. technical documents and information: a copy of the manufacturer's pressure vessel manufacturing qualification certificate, boiler pressure vessel product safety performance supervision and inspection certificate, pressure vessel product quality certificate, pressure vessel equipment general diagram, body diagram, technical characteristics table, as-built diagram, etc. complete and meet the specification requirements.
3. Equipment acceptance: equipment and spare parts name, specification, model, quantity in line with the design requirements and with the packing list; external dimensions and orifice orientation with the equipment diagram; appearance inspection without damage, deformation, rust and corrosion, etc., quality qualified.
4. Handover: After acceptance of the equipment, handover procedures should be carried out.
5. Equipment storage: equipment should be properly stored after unpacking, anti-corrosion, anti-damage, loss, etc., pipe mouths, manholes, etc. should be closed.
Equipment in place
1. Preparatory work before installation of equipment
Before installation, the installation datum line and positioning datum mark should be marked according to the design drawings or technical documents; for equipment associated or connected with each other, a common datum should also be determined according to the requirements of association or connection.
Before installation, the foot bolt of the equipment should be inspected and should not be damaged or rusted; the orientation mark, centre of gravity mark and hanging point of the equipment should be checked and should be supplemented if it does not meet the installation requirements.
Check the position and size of the equipment ground bolt holes and the foundation pre-buried bolts.
2. Handling of the foundation
The surface of the foundation of the equipment to be second grouted should be shovelled out of the pockmark, the depth of the pockmark is generally not less than 10mm, and the density of 3~5 points per square decimeter is appropriate.
The location of the pad iron should be shoveled flat, and the deviation of its level should be less than 2mm/m.
With the sliding end of the cold exchange equipment base, the sliding end of the pre-buried steel plate level deviation should be no more than 1mm / m, the surface should be cleaned before installation, and the sliding surface in contact with the equipment base should be coated with grease.
3. Mat iron setting
The pad iron is placed on both sides of the foot bolt, the inclined pad iron should be used in pairs, the lap length is not less than 3/4 of the full length, the pad iron group should be deep into the bottom of the equipment base length of the equipment foot bolt should exceed the centre, and grouting after leveling before welding firmly with positioning weld;.
The distance between two adjacent gasket sets should be about 500mm, each gasket set should reduce the number of gaskets, and should not exceed 5, and should not use thin gaskets.
The pad iron surface is smooth, no oxide skin, flying edge, etc..
4. Equipment lifting in position
Find the installation direction of the equipment according to the orientation of the process pipe mouth, and then use the crane to lift the equipment into position.
The alignment and leveling of the equipment should be adjusted and measured according to the installation datum line on the foundation (centre mark, level mark) corresponding to the datum measuring point on the equipment.
Levelling should be carried out in the same plane at right angles to each other in two directions.
Equipment levelling should be adjusted with a gasket according to requirements; it should not be adjusted by tightening or relaxing the foot bolt and local pressure.
After levelling or leveling, tighten the ground bolts and spot weld the pads into one.
For vertical equipment over 20 metres in height, to avoid meteorological conditions, the adjustment and measurement of plumbness should be avoided under conditions of sunlight on one side and wind force greater than 4.
For horizontal equipment subjected to expansion and contraction, check the expansion margin at the sliding end, loosen the ground bolt nuts at the sliding end by 1 to 3 mm and fasten them with locking nuts. For horizontal equipment with a sliding base plate, the bottom of the support should be cleaned and lubricated.
Pressure test
1. The pressure test of equipment and equipment with main flange connections shall be carried out in accordance with the following provisions.
Equipment in the manufacturing plant has been done pressure test, there is a complete quality certification documents and local boiler and pressure vessel supervision and inspection department supervision and inspection certificate, no damage and deformation in the process of transportation, the factory period of not more than six months, installation can no longer be pressure test re-inspection.
Equipment in the manufacturing plant after the pressure test, and equipment protected by gas seal, confirmed by the construction unit or supervisory unit before installation if the gas seal is intact, can no longer be pressure test re-inspection.
equipment that has been pressure tested at the factory, but has damage in the transportation process, the construction unit, supervision unit and the construction unit shall negotiate a pressure test re-inspection.
equipment assembled at the construction site shall be pressure tested.
When the contract has provisions, it should be implemented according to the contract provisions.
Pressure test to accept the local quality and technical supervision departments and supervision units on-site supervision and inspection.
2. The items and requirements of the pressure test of the equipment shall be carried out in accordance with the design drawings or design documents.
3. For equipment that does not allow a trace of residual liquid or is not allowed to be filled with liquid due to structure and support, etc., the air pressure test may be used.
4. pressure test, must use two range of the same, after calibration, and within the validity of the pressure gauge. The range of the pressure gauge should be 2 times the experimental pressure, but not less than 1.5 times and higher than 3 times, the accuracy shall not be less than 1.5 level, the diameter of the dial shall not be less than 100mm.
5. Pressure gauge should be installed in the highest and lowest part of the equipment; test pressure value, the highest pressure gauge reading should prevail, and use the lowest pressure gauge reading for calibration.
6. The appearance of the equipment should be checked before the test pressure, and its surface should be kept dry in order to check for leaks.
Cautions
1. Rust and dirt should be removed from the bolts, and the threaded part should be greased after removing the rust.
2. Safety precautions should be observed when installing equipment with coils.
3. Heat-treated equipment should be installed with special attention to.
(1) The gasket, insulation support ring and insulation nails on the equipment should be carefully checked during acceptance and must be in accordance with the drawings.
(2) equipment installation process is strictly prohibited in the equipment on the fire.
(3) Check whether the welding line is exposed, to prevent the welding line from being dragged in the process, fire on the equipment.
(4) The place where the fire is started should be clearly marked.
(4) The installation centre of the equipment should be positioned on the centre line of the foundation.
5. The verticality of the vertical equipment shall be based on the measuring points at the two ends of the equipment, and shall be measured at 90° with the magnetic wire drop and the steel plate ruler to ensure the verticality of the installation.
6. The horizontal degree of horizontal equipment should be measured by the centre line of the equipment, measured with a glass tube, and the level of the horizontal remeasurement flange should be used as a reference.
7. For horizontal equipment sliding end support of the long round hole and the position of the foot bolt should meet the working conditions of the rising and shrinking conditions, support plate and the bottom plate should be able to slide, equipment piping end, the foot bolt will be screwed loose to 1 ~ 3mm gap.
8. After the equipment gasket is corrected, it should be checked and confirmed by the construction unit and supervision company, and only after passing the concealed record can the secondary grouting be carried out.
Source: Chemical Equipment Man
Disclaimers.
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