Blast furnace shell installation preparation and construction process

1、Preparation for installation of blast furnace shell:

  1. Foundation treatment:

Before the installation of blast furnace shell, the handover data passing the foundation acceptance shall be obtained, including the measurement records of foundation overall dimension, center line and elevation and the inspection records of anchor bolts.

The size and position deviation of blast furnace foundation shall comply with the general provisions of the code for construction and acceptance of metallurgical mechanical equipment installation engineering. And extend the important center line to the fixed point outside the foundation.

  1. Preparation of hoisting site:

The blast furnace shell assembly platform is located in the south of the blast furnace (i.e. the foundation of the gravity dust collector, which will not be constructed temporarily). First level and harden the site near the furnace shell assembly platform and the crane station, and remove the obstacles affecting the hoisting.

  1. Preparation of machines and tools:

(1) Arrange rain proof electric welding machine shed, and install distribution board, electric welding machine and drying box.

(2) Set up on-site warehouse (machine room).

(3) The main crane is a 250t crawler crane.

2、 Installation of blast furnace shell:

  1. The main procedures of furnace shell installation are as follows:

(1) Install the furnace bottom beam and water cooling pipe, level and align, subject to the 0 ° center line, and set out the vertical and horizontal center lines of the furnace shell.

Allowable deviation of pre assembly of water cooling beam: mm

Inspection contents and allowable deviation inspection methods:

1) The height difference of all supporting beams shall be measured with D / 1000 feet.

2) The height difference between the corresponding points of two adjacent support beams shall be measured with 4 feet.

3) Measure the height difference of all cooling pipes of the water cooling beam with 6 feet.

4) Measure the center of each cooling pipe of the water cooling beam with 3 feet.

Allowable deviation of water cooling beam installation:

Inspection contents and allowable deviation inspection methods:

1) The elevation shall be measured with ± 10 feet.

2) D / 1000 level gauge for height difference of all supporting beams.

3) Height difference 4 level of corresponding points of two adjacent supporting beams.

4) Measure the center of each cooling pipe of the water cooling beam with 3 feet.

(2) Before installing the furnace bottom plate, the water cooling pipe at the bottom of the furnace must be subjected to a hydrostatic test. After the hydrostatic test is completed, the installation of the furnace bottom plate can be carried out. Lead the vertical and horizontal center lines of the furnace shell to the furnace bottom plate, bury the center plate at the center point, and drill a small hole of about 5mm on the center plate as the permanent center point.

Inspection contents and allowable deviation inspection methods:

Allowable deviation of base plate ring installation:

1) The center line shall be measured with 2 feet.

2) Upper surface levelness D / 1000 level.

3) The difference between the maximum and minimum diameters shall be measured with 2D / 1000 feet.

4) Measure the alignment and misalignment with 3 feet.

(3) Install the furnace shell. When the furnace shell is installed to the tuyere section, put the hot air enclosure pipe in and fix it with temporary support. After the furnace shell continues to be installed, align the hot air enclosure, and install branch pipes, valves, measurement and control systems and other pipes.

(4) The installation of furnace shell continues. When it is installed to the eighth belt, the installation of furnace shell shall be suspended and the installation of water wall shall be started. When the water wall is installed at the position of eight belt furnace shell, continue to install the furnace shell.

(5) When the furnace shell and steel brick are installed, the upper part of the steel brick shall be sealed with a hanging plate to prevent falling objects during the above construction. The furnace construction starts, and other work shall continue above the furnace shell.

(6) For furnace shell hoisting, clean the hoisting area and remove the obstacles that hinder the crane walking and boom movement. After the hoisting and welding of the first belt furnace shell is completed, the hoisting and welding of the second belt furnace shell shall be carried out. Pay attention to the alignment and mark the angle and center line. When the alignment is completed and not welded, the upper level, elevation and center line of the second belt furnace shell shall be measured, and the welding shall be carried out after adjustment. Then carry out the hoisting and welding of the lower furnace shell in turn. Pay attention to strictly control the elevation and center line of the iron mouth and tuyere when installing the furnace shell with iron mouth belt and tuyere belt.

(7) After the inner side is welded, the outer side shall be polished manually and the weld shall be repaired. The appearance quality of the weld shall comply with the ybj205-85 standard for weld surface quality. The weld after repair welding shall be in accordance with the original standard jb1152-81, and the number of repairs shall not exceed twice.