【Abstract】The furnace silver installation of hot-dip galvanizing vertical continuous annealing furnace mainly includes the installation of bearing support beam, furnace roller bearing seat, furnace roller cover, expansion joint, furnace roller, furnace roller bearing and other parts.
The installation of furnace rolls is the most important, complex and demanding part of furnace installation. The installation structure of furnace rollers is complex, there are many small parts, the equipment layout is compact, and the installation accuracy is high. The quality of its installation determines the operation of the steel strip in the furnace. This means that the installation quality of the furnace rolls determines the continuity of the production of the galvanizing line.
This paper expounds in detail the method of installation and adjustment of the furnace rolls of the vertical continuous annealing furnace of a hot-dip galvanizing line in a cold rolling project, the main points in the process, and the matters needing attention.
The installation of furnace rolls is an important part of the whole annealing furnace installation process. The installation quality determines whether the continuous production of the galvanizing line can be guaranteed. It is usually the most precise installation work of the furnace body, and it is also the most precise installation of the furnace body. The work before the test run affects the oven of the annealing furnace. The accuracy of furnace roll adjustment also directly affects the correction adjustment of the furnace body strip, which has a significant impact on the straight passing of the furnace body in the later stage. Therefore, the accuracy of furnace roll adjustment and the speed of adjustment will directly affect the total construction period of the entire hot-dip galvanizing line. Furnace roller equipment is mainly composed of rollers, transmission devices and roller accessories. The roller accessories include bearing seats, bearings, expansion joints, etc.
Installation and adjustment of furnace rolls
Installation prerequisites
(1) The installation of the main steel structure of the furnace area is completed;
(2) Determine the final tightening of all bolts and reach the specified torque value;
(3) The installation and welding of the furnace shell are completed, and it has passed the acceptance inspection of on-site foreign experts and supervisors and confirmed that it is qualified.
(4) After the furnace area structure installation is completed, after acceptance, set auxiliary points and reference lines for furnace roller installation, adjustment and acceptance on the steel structure platform (confirm that all structural bolts have been tightened and meet the bolt torque requirements;
(5) Technical description: The reference line elevation of the bottom (top) layer is 200mm higher than the furnace roller elevation: the reference lines on both sides are 1970mm away from the center of the furnace body.
Install the drive side and operation side bearing support beams
(1) Adjust and accept according to the center elevation of the furnace roll window on the operation side
(2) The content to be measured and the allowable error values for acceptance are as follows:
1) Inspection content: the distance from the center of the furnace roller to the bearing dyeing (operation side), the technical requirement value is ±2mm;
2) Inspection content: the distance between both sides (drive side), the technical requirement value is ±2mm;
3) Inspection content: the horizontal distance from the beam to the reference line (operation side), the technical requirement value is ±2mm:
4) Inspection content: The technical requirement for the horizontal distance from the horizontal dyeing to the reference line (drive side) is ±2mm.
Adjust the positioning of the drive side furnace roll cover
(1) Take off the drive side roller cover and carry out heat preservation work first;
2) Position, adjust and accept according to the center elevation of the furnace roll window on the operation side. After acceptance, weld the outside of the angle steel at the contact between the furnace roll cover and the furnace shell.
(3) The content to be measured and the allowable error values for acceptance are as follows:
1) Inspection content: The central elevation of the furnace silver cover (drive side), the technical requirement value is ±2mm.
2) Inspection content: the central elevation of the furnace roll cover (operation side), the technical requirement value is ±2mm.
3) Inspection content: the horizontal distance of the furnace roll cover (drive side), the technical requirement value is ±2mm. 4) Inspection content: the horizontal distance of the furnace roll cover (operation side), the technical requirement value is ±2mm.
Installing the drive side furnace roll chock
(1) Adjust and accept the elevation, verticality and parallelism with the auxiliary line of the bearing housing. (2) The content to be measured for acceptance and the allowable error values are as follows:
1) Inspection content: The center elevation of the bearing housing (drive side), the technical requirement value is 0~-1mm.
2) Inspection content: the center elevation of the bearing seat (operation side), the technical requirement value is 0~+2mm.
3) Inspection content: the verticality of the bearing seat (drive side), the technical requirement value is ±1mm/m. 4) Inspection content: the verticality of the bearing seat (operation side), the technical requirement value is ±1mm/m. 5) Inspection content: the parallelism of the bearing seat (drive side), the technical requirement value is ±1mm/m. 6) Inspection content: the parallelism of the bearing seat (operation side), the technical requirement value is 0.5mm/m.
Installing the drive side furnace roll expansion joint
(1) When installing the top drive side expansion joint, the elevation of the bearing seat side must be adjusted to be +12mm higher than the elevation of the furnace shell side according to the drawings, and the verticality of the silver cover must be ensured.
(2) Adjust and check the bearing seat on which the expansion joint is installed, and then weld the other side of the angle steel of the furnace roll cover after completion.
Pre-installed operating side furnace roll cover
(1) When installing the furnace roll cover on the operation side, if all the bolt holes are suitable, just install the 4 bolts on the corners.
(2) Adjust the elevation and verticality of the roll cover. After acceptance, weld the outside of the angle steel at the contact between the furnace roll cover and the furnace shell.
(3) After welding, use a grinder to grind the temporary welding spot on the outer side of the angle steel, remove it, and carry out heat preservation work.
(4) Reinstall it to its original position after insulation.
(5) Acceptance form: the same as the drive side acceptance form.
Pre-installed operating side bearing housing
(1) Adjust and accept the elevation, verticality, and parallelism of the bearing housing with the rolling line of the furnace body;
(2) After the acceptance, weld 3 points at the connection between the positioning block and the support beam, and position them for re-installation;
(3) Number the roll cover and the bearing seat, so that the number can be checked and seated when re-installing;
(4) Remove the bearing seat on the operating side;
(5) Acceptance form: the same as the acceptance form of the drive side bearing seat.
Installing the furnace rolls
Install the furnace silver from the operation side into the furnace with the special lifting tool provided by the external party
Installation of operating side expansion joints, bearing housings and bearings
(1) Technical description:
1) First reset and adjust the bearing seat;
2) Tighten the bolts on both sides of the expansion joint:
3) Install the bearing and adjust the bearing clearance;
4) Measure the dimensions from the bearing to the outside of the bushing and the end of the furnace roll;
5) Install the bearing lock nut;
6) Acceptance of the adjusted bearing clearance and ruler;
7) Install the outer end cover of the furnace roll;
8) After acceptance, weld the outside of the angle steel of the furnace roll cover
Acceptance
The content to be measured and the allowable error values for acceptance are as follows:
1) Inspection content: a value (drive side), the technical requirement value is ±1mm:
2) Inspection content: Bearing clearance (drive side), the technical requirement value is 0.1~0.15mm:
3) Inspection content: b value (drive side), the technical requirement value is ±2mm;
4) Check content: value (operation side), the technical requirement value is ±5mm:
5) Inspection content: Bearing clearance (operation side), technical requirement value is 0.1~0.15mm:
6) Inspection content: E value (exit) (operation side), technical requirement value is 0~0.15mm:
7) Inspection content: Port value (inlet) (operation side), technical requirement value 0~0.15mm:
8) Inspection content: A value (upper side) (operation side), the technical requirement value is 0-0.15mm;
9) Inspection content: B value (lower side) (operation side), technical requirements 1½ 0~0. 15mm.
Install the furnace roll drive
(1) Technical requirements: install and adjust the drive-side transmission, adjust the concentricity between the motor, coupling, and furnace rollers
(2) Acceptance drawing
(3) The content to be measured and the allowable error value for acceptance are as follows.
1) Inspection content: flange spacing (I), the technical requirement value is ±1mm.
2) Inspection content: concentricity, the technical requirement value is 0.2mm.
Precautions during equipment installation and adjustment
(1) Pay attention to the re-measurement of the center line of the furnace body, because the structural nodes of the furnace body are mainly connected by bolts. After the bolts are finally tightened, the center line and elevation points of the furnace body should be re-measured.
(2) After the furnace roller bearing is assembled, it is necessary to fasten the lock nut of the bearing with a special tool before the furnace silver acceptance can be carried out. Fastening data and tools should be provided by the furnace roll design unit
(3) The acceptance work of the furnace roll must be carried out step by step. After each step of acceptance is completed, the acceptance party needs to determine the data before proceeding to the next step of acceptance to avoid rework.
