On 2018-08-08 14:48:54
Annealing furnace installation method of continuous
1. Steel structure installation of furnace platform. Based on the construction methods at home and abroad and the practical experience of field installation, we summarize it as the installation method of "well" shaped frame assembled by sections on the ground, and then hoisting and positioning the "well" shaped frame.
The installation of steel structure of continuous annealing furnace is divided into two sections: lower, middle and upper. The installation of the lower section is the foundation of the whole steel structure, and the installation accuracy must be strictly controlled.
The installation of the middle section mainly controls the perpendicularity requirements of the steel structure to ensure the correct stress transfer of the upper section structure and equipment.
The installation of the upper section of steel structure is also the requirement of controlling the perpendicularity of the steel structure to ensure the correctness of the stress on the joint position.
For the installation of steel platform frame, in addition to the "well" frame assembled on the ground, the walking platform on this section of steel structure shall also be installed. The installation of the walking platform structure between each two frames needs to be carried out by single lifting to the frame.
The ladder handrail shall be installed layer by layer along with the platform installation.
2. Installation of furnace shell. The installation of furnace shell is also divided into the lower, middle and upper sections, that is, the installation of furnace bottom chamber, furnace side plate and furnace top chamber. Whether it is an independent furnace shell structure or a furnace shell structure installed on the steel structure of the furnace, the correct installation of the furnace bottom chamber is also related to the quality of the furnace shell installation, and the quality control of the furnace bottom chamber must be strictly implemented.
The perpendicularity of the furnace wall panel in the middle section is mainly controlled, and the adjustment of elevation should also be noted. For the furnace with resistance band in the tenth furnace, the height control of the retaining wall panel in the furnace should also be considered, otherwise it will cause unnecessary trouble to the masonry of the furnace. The leg size of the radiation tube corresponding to the installation of the two furnace side plates and the size of the radiation tube must be controlled.
The installation of the upper furnace top chamber is also one of the main control items. The first is to determine the distance between the top roll and the bottom roll mounting hole; the second is to control the basic size of the furnace roll mounting hole.
3. Installation of continuous annealing furnace roll. The installation of the furnace roll is divided into two parts: the upper and the lower furnace rolls. The lower furnace rolls are hoisted into the lifting trolley with special spreader, and then the components at both ends are assembled. After the upper furnace roll is hoisted in with a special sling, it shall be hoisted with a chain block, and then the components at both ends shall be assembled. The heating expansion of furnace shell shall be considered for the installation of upper furnace roll, and the clearance adjustment of bearing shall be paid attention to during the installation of furnace roll. Take the original state clearance of the bearing measured during installation as the initial value, then tighten the locking cap of the bearing, loosen the locking cap of the bearing after measuring the minimum value, adjust the measured bearing clearance until it reaches the value required by the design, and then install other components.
4. Installation of furnace lining plate. The installation of furnace inner lining plate is a remarkable feature of the replacement furnace. It is a structural way that the new type of heat preservation material in the furnace replaces the old one, and the stainless steel inner lining plate is used to seal the heat preservation material outside.
The inner lining plate is installed by the lifting platform in the furnace, which is much more convenient than the scaffold.
The first process of inner lining plate installation is to weld the heat preservation nails on the side plate of the furnace. Whether it is directly welding the heat preservation nails or first welding the nuts of the heat preservation nails, then welding the heat preservation nails as the nuts. After welding, quality inspection should be carried out. This is the key process of the construction of the heat preservation layer of the furnace, which should be strictly controlled.
After the completion of the construction of furnace building insulation layer, screw in the back nut of the inner panel, and spot weld for fixation.
After the stainless steel inner liner is installed, spot welding shall be carried out after the outer nuts of the inner liner are tightened. After welding, the welding coating shall be removed in time to avoid falling off in the future production process affecting the belt quality.
5. Air tightness test of furnace. The air tightness test of the furnace shall be carried out in sections, so as to find out whether the tightness of each furnace section can meet the design requirements, and whether the minimum control conditions for production can be met in the furnace under the control of protective gas, which is the key to whether the products produced can meet the quality requirements.
In the air tightness test, a gas source and a protection device are respectively connected to each furnace in the section, and the test method of checking the change of water column is adopted. Firstly, the continuous annealing furnace is filled with gas to detect the furnace body weld and other sealing parts to see if there is any leakage. After the treatment of the leakage source of the furnace body, the gas source is shut down. The gas in the furnace should be kept still for a period of time to check the change of water column, and finally determine whether the air tightness test of the furnace body is qualified. After qualified, remove the blocking plate in the furnace and prepare for oven drying.