Construction method for improving installation precision of steam turbine generator

Abstract

The invention discloses a construction method for improving the installation precision of a steam turbine generator. The construction method comprises the steps of equipment unpacking, checking and acceptance, foundation installation, control over rebar bundling construction, centering and fine inspection, foundation acceptance, center line correction, open file size correction, foundation alignment, embedded part checking and inspection, deviation treatment, expansion smoothness, bearing box cleaning and the like. The construction method comprises the steps of equipment unpacking, checking and acceptance, foundation installation, control over rebar bundling construction, centering and fine inspection, foundation acceptance, center line correction, open file size correction, foundation alignment, embedded part checking and inspection, deviation treatment, expansion smoothness, bearing box cleaning and the like. By controlling part management, basic acceptance and installation precision, the fault risk in equipment operation is reduced, the quality of each link is ensured, equipment faults caused by local problems are reduced, the fault risk in equipment operation is further reduced, the service life of equipment is prolonged, and the maintenance cost of the equipment is reduced.

Description

Technical Field

[0001] The present invention relates to a construction method for steam turbines, and particularly to a construction method for improving the installation accuracy of turbo-generators, belonging to the technical field of steam turbine installation. Background Art

[0002] In modern thermal power plants, nuclear power plants, and large industrial steam turbines and other application scenarios, as the core power equipment, the construction and installation quality of turbo-generators is directly related to the operation stability, safety, and service life of the equipment. In the construction and installation process of turbo-generators, links such as equipment unpacking and inventory taking, foundation construction and acceptance, and technical control during installation are crucial for the installation accuracy and operation stability of the equipment; in the prior art, problems such as disorderly storage of parts, omissions in foundation construction acceptance, and technical deviations during installation may exist in these links, and these problems may lead to difficult equipment installation, unstable operation, and even safety accidents; therefore, an installation method that can ensure construction and installation quality is needed. Summary of the Invention

[0003] The technical problem to be solved by the present invention is: to overcome the deficiencies of the prior art, provide a construction method for improving the installation accuracy of turbo-generators, and ensure the installation quality of turbo-generators, and improve the operation stability and safety of the equipment by optimizing the construction steps.

[0004] The technical solution adopted by the present invention to solve the technical problem is: A construction method for improving the installation accuracy of turbo-generators includes the following steps: S1. Construction Preparation: ①. After the equipment arrives, conduct an inventory, and clean and remove rust from the equipment and parts. ②. For equipment and parts that are not temporarily used, reinstall them in the original position in the box and seal the packing box; for precision and small parts, they should be stored in the warehouse and marked. S2. Verification before Foundation Construction: ①. The longitudinal and transverse centerlines of the foundation should be consistent with the positions of the longitudinal and transverse centerlines of the installation. ②. The positions of the embedded anchor bolts and embedded iron should meet the installation requirements. ③. Reserve oil pipes and embedded pipe base grooves, and the base grooves meet the expansion requirements during installation and operation. ④. The distance between the four walls of the foundation empty space corresponding to the high-pressure cylinder and the intermediate-pressure cylinder and the cylinder should meet the expansion requirements of the cylinder during operation. S3. Verification during and after Foundation Construction: ①. During the bundling of each layer of foundation steel bars, the positions, quantities, and elevations of the embedded parts should meet the installation requirements. ②. Each embedded part shall have reliable fixing measures to prevent deviation during the concrete pouring process. ③. After the concrete pouring of the steam turbine generator foundation is completed, acceptance can be carried out to ensure that the foundation surface is flat, without appearance defects such as honeycombing, pitting, cracks, and exposed reinforcement. Installation work can be carried out only when the concrete strength reaches 70% of the design strength. ④. Pull steel wires along the longitudinal center line of the steam turbine generator and the transverse center line of the low-pressure cylinder, and calibrate the perpendicularity of the two steel wires. Based on the longitudinal and transverse center line steel wires, check the position deviation of each anchor bolt and embedded iron one by one. Mark the transverse center lines of each bearing pedestal, generator stator, and carbon brush holder on the foundation. ⑤. Calibrate the open dimension at the corresponding cylinder and stator of the foundation to ensure its accuracy and not affect the equipment installation and expansion during operation. ⑥. Use a plumb bob to drop from the longitudinal and transverse center line steel wires of the steam turbine to the condenser foundation to ensure that the longitudinal and transverse center lines of the steam turbine and the condenser foundation correspond accurately. S4. Foundation installation: ①. Make cement blocks and arrange them reasonably. There should be no void or gap between the cement pads and the soleplate, and the contact should be dense. ②. The bearing housing should slide smoothly and without collision with the soleplate; there should be no gap and the contact should be dense between the low-pressure cylinder base frame and the soleplate. ③. The foundation should be in firm contact with the cement pads, the cement pads with the soleplate, and the soleplate with the bearing housing, without suspension or gap. ④. Control the expansion of the steam turbine body. Before installing the sliding key system, it should be cleaned thoroughly. The sliding keys, key grooves, keys, and adjusting pads should be smooth without burrs, parallel without deviation, the peripheral chamfers should meet the requirements, and the measured dimensions should be accurate. ⑤. When installing the sliding keys, leave the gap on one side to ensure free expansion without distortion or deviation. Ensure that the clearance between the diaphragms and diaphragm sleeves in the cylinder body and the cylinder body meets the requirements. ⑥. The radial expansion clearances of each hanger and guiding key should meet the requirements. Ensure that the sliding mating surfaces on each box body and cylinder body are cleaned without impurities. S5. Cleaning of the bearing housing: ①. Clean the bearing housing, avoiding dead corners and preventing oil system pollution. ②. When installing the bearings, ensure that the grinding between the pads and the bearing body, the pads and the bearing housing, and the contact between the bearing body and the spherical surface reach 85%, and the distribution is uniform. ③. Check the contact surface, contact angle, and jacking oil pocket size between the bearing bush and the journal to ensure that the bearing gap meets the requirements. S6. Verification of the alignment construction of the steam turbine: ①. When inspecting the rotor, the bending value of the rotor, the offset of the coupling, the runout, the journal runout value, the journal ovality and cylindricity should be measured, and the fasteners on the rotor impeller, the expansion gap of the shroud ring and the fastening condition of the balance weight should be checked to meet the requirements; ②. When aligning the coupling, the method of reserving height difference is used for alignment. After the bearing bushes are ground, the center of the shafting is adjusted by adding temporary gaskets; ③. When adjusting the steam seal clearance and the flow passage clearance, it should be ensured that the steam seal blocks slide freely without jamming; ④. When distributing the load, the load should be reasonably distributed to reduce the cylinder deformation, enhance the cylinder rigidity. At the same time, the cylinder levelness and the journal elevation of the rotor should meet the requirements; ⑤. Measure the minimum axial clearance inside the cylinder to ensure that the minimum axial clearance does not prevent the free expansion of the rotor, and the axial dimensions of the corresponding mating positions of each boss of the rotor and the oil baffle of the bearing housing should meet the requirements; ⑥. After the cylinder is positioned, the connection with the condenser can be carried out; the main extraction pipes connected to the cylinder are freely connected without forced butt joint.

[0005] The positive and beneficial effects of the present invention are as follows: 1. By controlling the technology during the unpacking and inventory checking of equipment, foundation construction and acceptance, and installation process, the quality of each link is ensured, the equipment failure caused by local problems is reduced, the failure risk during equipment operation is further reduced, the service life of the equipment is extended, and the maintenance cost of the equipment is reduced.

[0006] 2. Through strict classification, fixed-position storage and identification management, the problems of component confusion, loss and misalignment during reinstallation are avoided, and the integrity and usability of components are ensured.

[0007] 3. By checking the key parameters such as the elevation, external dimensions, longitudinal and transverse centerlines, anchor bolt holes, embedded parts, etc. of the foundation, it is ensured that the foundation construction meets the design requirements, providing a solid foundation for equipment installation.

[0008] 4. By optimizing the installation and adjustment of the sliding key system, the free expansion of the equipment under high temperature and high pressure conditions is ensured, and the vibration and stress concentration problems caused by uneven expansion are reduced. Detailed implementation manners

[0009] The following further explains the present invention: Embodiment, a construction method for improving the installation accuracy of a steam turbine generator, includes the following steps: S1. Construction preparation: ①. After the equipment arrives, it is inventoried, and the equipment and components are cleaned and derusted; ②. For the equipment and components that are not to be used temporarily, reinstall them in place in the box and seal the packing box. For precision and small components, they should be stored in the warehouse and properly labeled. S2. Verification before foundation construction: ①. The longitudinal and transverse centerlines of the foundation should be consistent with the positions of the longitudinal and transverse centerlines of the installation. ②. The positions of the embedded anchor bolts and embedded iron should meet the installation requirements. ③. Reserve oil pipes and embedded pipe foundation trenches, and the trenches should meet the expansion requirements during installation and operation. ④. The distance between the four walls of the foundation gap corresponding to the high-pressure cylinder and the intermediate-pressure cylinder and the cylinder should meet the expansion requirements of the cylinder during operation. S3. Verification during and after foundation construction: ①. The positions, quantities, and elevations of the embedded parts during the bundling of each layer of foundation steel bars should meet the installation requirements. ②. Each embedded part should have reliable fixing measures to prevent deviation during the concrete pouring process. ③. After the concrete pouring of the steam turbine generator foundation is completed, acceptance can be carried out to ensure that the foundation surface is flat, without appearance defects such as honeycombing, pitting, cracks, and exposed reinforcement. Installation work can be carried out when the concrete strength reaches 70% of the design strength. ④. Pull steel wires along the longitudinal centerline of the steam turbine generator and the transverse centerline of the low-pressure cylinder, and calibrate the perpendicularity of the two steel wires. Based on the longitudinal and transverse centerline steel wires, check the position deviation of each anchor bolt and embedded iron one by one. Mark the transverse centerlines of each bearing pedestal, generator stator, and carbon brush holder on the foundation. ⑤. Calibrate the open size of the foundation corresponding to the cylinder and stator to ensure its accuracy and not affect the equipment installation and expansion during operation. ⑥. Use a plumb bob to hang down from the longitudinal and transverse centerline steel wires of the steam turbine to the condenser foundation to ensure that the longitudinal and transverse centerlines of the steam turbine and the condenser foundation correspond accurately. S4. Foundation installation: ①. Make cement blocks, arrange the cement pads reasonably, and there should be no voids or gaps between the cement pads and the soleplate, and the contact should be dense. ②. The bearing box should slide smoothly and without collision with the soleplate; there should be no gap between the low-pressure cylinder base frame and the soleplate, and the contact should be dense. ③. The foundation should be in firm contact with the cement pads, the cement pads with the soleplate, and the soleplate with the bearing box, without suspension or gaps. ④. Control the expansion of the steam turbine body. Before installing the sliding key system, it should be cleaned thoroughly. The sliding keys, key grooves, keys, and adjusting pads should be smooth without burrs, parallel without deviation, the peripheral chamfers should meet the requirements, and the measured dimensions should be accurate. ⑤. When installing the sliding pins, leave the gap on one side to ensure free expansion without distortion or deviation; ensure that the clearance between the diaphragms, diaphragm sleeves and the cylinder body in the cylinder meets the requirements. ⑥. The radial expansion clearances of each hanger ear and guiding key should meet the requirements. Ensure that the sliding mating surfaces on each casing and cylinder body are cleaned without impurities. S5. Cleaning of the bearing housing: ①. Clean the bearing housing, avoiding dead corners to prevent oil system contamination. ②. When installing the bearings, ensure that the grinding between the spacer blocks and the bearing shells, between the spacer blocks and the bearing pedestals, and the contact between the bearing shells and the spherical surfaces reaches 85% and is evenly distributed. ③. Check the contact surface, contact angle between the bearing bush and the journal, and the size of the jacking oil pocket to ensure that the gap at the bearing bush mouth meets the requirements. S6. Verification of the alignment construction of the steam turbine: ①. When checking the rotor, the bending value of the rotor, the deflection of the coupling, the runout, the journal runout value, the journal ovality and non-cylindricity should be measured, and the fasteners on the rotor impeller, the expansion clearance of the shroud ring and the fastening condition of the balance weight should be checked to meet the requirements. ②. When aligning the coupling, the method of reserving height difference is used for alignment. After the bearing bush grinding is completed, the method of adding temporary gaskets is used to adjust the shafting center. ③. When adjusting the steam seal clearance and the flow passage clearance, ensure that the steam seal blocks slide freely without jamming. ④. When distributing the load, the load should be reasonably distributed to reduce the cylinder deformation, enhance the cylinder rigidity. At the same time, the cylinder levelness and the journal elevation of the rotor should meet the requirements. ⑤. Measure the minimum axial clearance in the cylinder to ensure that the minimum axial clearance does not prevent the free expansion of the rotor, and the axial dimensions of the corresponding mating positions of each boss of the rotor and the oil baffle of the bearing pedestal should meet the requirements. ⑥. After the cylinder is positioned, the connection with the condenser can be carried out; the main extraction pipes connected to the cylinder should be freely connected without forced butt joint.

[0010] In the above description, before the construction of the steam turbine generator set foundation, the supervisor should organize the civil engineering, installation and other professionals to conduct a drawing review to check whether there are inconsistencies between the civil engineering and installation drawings, and clarify the construction demarcation line and quality responsibility. In this process, it is easy to have omissions due to careless drawing checking and unclear construction demarcation; during the foundation construction period, the installation unit should track and check whether the special dimensions, embedded parts, etc. related to the pedestal and equipment installation are correct.

[0011] In the above description, the position and specification of the embedded iron should meet the installation requirements, especially pay attention to the embedded iron for the installation of the high and medium pressure main steam valves and governing valves; the distance between the low cylinder sunken platen and the foundation should be appropriate for easy adjustment of the platen.

[0012] In the above description, the open dimension of the base corresponding to the cylinder, stator, etc. should be accurate and should not affect the installation of the equipment and its expansion during operation.

[0013] By controlling the technology in the processes of unpacking and inventorying the equipment, foundation construction and acceptance, and installation, the present invention ensures the quality of each link, reduces equipment failures caused by local problems, further reduces the failure risk during equipment operation, extends the service life of the equipment, and reduces the maintenance cost of the equipment.

[0014] By controlling the component management, foundation acceptance and installation accuracy, the present invention reduces the failure risk during equipment operation, ensures the quality of each link, reduces equipment failures caused by local problems, further reduces the failure risk during equipment operation, extends the service life of the equipment, and reduces the maintenance cost of the equipment.

Claims

1. A construction method for improving the installation accuracy of a steam turbine generator, characterized in that, It includes the following steps: S1. Construction preparation: ①. Conduct an inventory after the equipment arrives, and clean and remove rust from the equipment and its components. ②. For the equipment and components that are not to be used temporarily, reinstall them in the original position into the boxes and seal the packing boxes. For precision and small components, they should be stored in the warehouse and properly labeled. S2. Verification before foundation construction: ①. The longitudinal and transverse centerlines of the foundation should be in line with the positions of the longitudinal and transverse centerlines of the installation. ②. The positions of the embedded anchor bolts and embedded iron should meet the installation requirements. ③. Reserve oil pipes and embedded pipe trenches, and the trenches should meet the expansion requirements during installation and operation. ④. The distances between the four walls of the foundation empty spaces corresponding to the high-pressure cylinder and the intermediate-pressure cylinder and the cylinder should meet the expansion requirements of the cylinder during operation. S3. Verification during and upon acceptance of foundation construction: ①. The positions, quantities, and elevations of the embedded parts during the bundling of each layer of base steel bars should meet the installation requirements. ②. Each embedded part should have reliable fixing measures to prevent deviation during the concrete pouring process. ③. After the concrete pouring of the steam turbine generator foundation is completed, acceptance can be carried out to ensure that the foundation surface is flat, without appearance defects such as honeycombing, pitting, cracks, and exposed reinforcement. Installation work can be carried out only when the concrete strength reaches 70% of the design strength. ④. Pull steel wires along the longitudinal centerline of the steam turbine generator and the transverse centerline of the low-pressure cylinder, and calibrate the perpendicularity of the two steel wires. Based on the longitudinal and transverse centerline steel wires, check the position deviations of each anchor bolt and embedded iron one by one. Mark the transverse centerlines of each bearing pedestal, generator stator, and carbon brush holder on the foundation. ⑤. Calibrate the open dimension of the foundation corresponding to the cylinder and the stator to ensure its accuracy and not affect the equipment installation and expansion during operation. ⑥. Based on the longitudinal and transverse centerline steel wires of the steam turbine, hang a plumb bob to the condenser foundation to ensure that the longitudinal and transverse centerlines of the steam turbine and the condenser foundation correspond accurately. S4. Foundation installation: ①. Make cement blocks, arrange the cement pads reasonably, and there should be no voids or gaps between the cement pads and the soleplate, and the contact should be dense. ②. The bearing housing and the soleplate should slide smoothly without collision; there should be no gaps between the low-pressure cylinder base frame and the soleplate, and the contact should be dense. ③. The foundation, cement pads, cement pads and soleplate, and soleplate and bearing housing should be in firm contact, without suspension or gaps. ④. Control the expansion of the steam turbine body. Before installing the sliding key system, it should be cleaned thoroughly. The sliding keys, key grooves, keys, and adjusting pads should be smooth without burrs, parallel without deviation, the peripheral chamfers should meet the requirements, and the measured dimensions should be accurate. ⑤. When installing the sliding keys, leave the gap on one side to ensure free expansion without distortion or deviation; ensure that the clearance between the diaphragms and diaphragm sleeves in the cylinder body and the cylinder body meets the requirements. ⑥. The radial expansion clearances of each hanger and guiding key should meet the requirements, ensure that the sliding mating surfaces on each box body and cylinder body are cleaned without impurities. S5. Cleaning of the bearing housing: ①. Clean the bearing housing, avoiding dead corners to prevent oil system pollution. ②. When installing the bearings, ensure that the grinding between the pads and the bearing body, the pads and the bearing housing, and the contact between the bearing body and the spherical surface reach 85% and are evenly distributed. ③. Check the contact surface, contact angle, and jacking oil pocket size between the bearing bush and the journal to ensure that the bearing gap meets the requirements. S6. Verification of turbine centering construction: ① When inspecting the rotor, the rotor bending value, wheel eccentricity, wobble, journal runout value, journal ovality and non-cylindricity should be measured, and the fasteners on the rotor impeller, the compound ring expansion gap and the fastening of the balancing block should be checked to ensure that they meet the requirements; ② When finding the center of the wheel, the reserved height difference method is used for centering. After the grinding of the bearings is completed, the center of the shaft system is adjusted by adding temporary gaskets; ③ When adjusting the steam seal clearance and flow clearance, ensure that the steam seal block slides freely without getting stuck; ④. When distributing load, the load should be distributed reasonably to reduce cylinder deformation and enhance cylinder rigidity. At the same time, the cylinder horizontality and rotor journal lift should meet the requirements; ⑤. Measure the minimum axial clearance in the cylinder to ensure that the minimum axial clearance does not hinder the free expansion of the rotor, and the axial dimensions of the rotor bosses and corresponding matching positions and the bearing seat oil baffles should meet the requirements; ⑥. The connection with the condenser can be made only after the cylinder is positioned; the main steam extraction pipe connected to the cylinder should be connected freely and not forcibly.