Processing construction of non-standard parts for

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Safety measures for non-standard parts processing and construction of air shaft pipe beam and drainage pipeline installation

I. project overview:

the diameter of the air shaft in the center of Suncun mine is ¢ 6.0m, and the depth of the shaft is 975.3m. At the south side of the shaft and the target middle line of the East-West mark of the shaft, the i20a device is installed in parallel from the wellhead to the bottom of the shaft, with a layer spacing of 6m. Factor 5: 155 layers of I-steel clip beam of the force value sensor of the electronic tensile testing machine, The pipe clamping beam is firmly connected with the bracket fixed on the shaft wall by bolts and resin anchor bolts. 14 sets of pipe seat beams are used to bear the weight of the upper pipe section at each elevation of the shaft. The total weight of non-standard parts in the shaft is about 100t. The drainage pipeline is made of two ¢ 377 seamless steel pipes. The wall thickness of the pipeline is divided into three sections according to the depth of the shaft: the first section is made of ¢ 37710 seamless steel pipes from + 199.40m to - 200.00m, the second section is made of ¢ 37716 seamless steel pipes from - 200.00m to - 600.00m, and the third section is made of ¢ 37722 seamless steel pipes from - 600.00m to - 775.00m. The total component of the drainage pipeline is 258t. The general derusting quality grade of metal components shall meet the Swedish standard Sa2.5. After arc zinc spraying, one coat of epoxy asphalt primer and two coats of epoxy asphalt finish paint shall be applied. The production of non-standard parts and the derusting and anti-corrosion of steel components are in large quantities, with high technical quality requirements, and the construction period of this device project is tight, so it must be introduced into the production of walking non-standard parts and the derusting and anti-corrosion of steel components. The production of non-standard parts is in the original repair plant, and the derusting and anti-corrosion of steel components is stopped in Xintai development zone

2. Construction content:

(I) production of non-standard parts

1 155 pipe clamping beams 18886 kg

2 155 pieces of No.1 bracket 4914 kg

3 155 pieces of No. 2 bracket 4914 kg

4 14 stinger beams 24250 kg

5 Combined channel steel (I) 14 pieces 3009 kg

6 Combined channel steel (II) 14 pieces 2486 kg

7 Welded straight pipe base DN350, pn=10.0mpa, 6 pieces 4212 kg

8 Welded straight pipe base DN350, pn=6.4mpa, 8 4054 kg

9.90. Elbow DN350, pn=10.0mpa, 2 pieces 926 kg

10.90. Elbow DN350, pn=1.0mpa, 2 pieces 405kg

11 1240 base plates 856 kg

12 620 clamping base plates 1748 kg

(II) rust removal and corrosion prevention of steel members

1 Derusting and anti-corrosion of non-standard parts 100t

2 Pipeline rust removal and corrosion prevention 258t

3. Construction method and process:

(I) non standard parts production

the production process of non-standard parts is as follows: steel → blanking → assembly and spot welding → welding → correction → finished products

1 Preparation task before processing

(1) review the drawings before processing, check whether the design depth of the drawings can meet the construction requirements, check the number of components and device size on the drawings, check whether there are contradictions between components, and stop the process review, whether the review authority is convenient for construction, and whether its technical requirements can be completed according to the existing equipment and degree of our company

(2) stop checking the specification, material and weight of the data required by the drawing. If the data substitution is stopped, it must be agreed by the design department, and all the reference specifications and relevant dimensions on the drawing must be corrected

(3) the inspection system shall be strictly implemented for the goods, and the use of materials without quality certificates is strictly prohibited

(4) make detailed technical disclosure records

2. Processing

(1) release a 1:1 large sample on the platform, check the size of each part, and make a template, which indicates the drawing number, part number, quantity, processing edge, position of the part, etc

(2) marking off: check the data, mark the cutting and drilling processing positions on the data, punch holes, and mark the part number. When marking off, try to stop the data nesting, and leave appropriate processing residue according to the data thickness and cutting method

(3) blanking: all small plates ≤ 12 mm are sheared, ultra long or ultra thick plates are cut by gas cutting machine, and section steel is cut by gas cutting or sawing

(4) profile steel is straight: the deflection height of profile steel f ≤ l/1000 and ≤ 5mm, and the inclination of I-steel flange plate △≤ b/80; Partial deflection of steel plate δ ≤ 14, f ≤ 1.5; δ> At 14, f ≤ 1. If the above requirements cannot be met, stop correcting the steel

3. Assembly

(1) during the production of steel components, in order to prevent welding deformation, fully operate various clamping molds to increase the amount of plastic repair. When inserting and assembling the mold, its positioning should consider the extension of the component, and adjust the reserved amount at any time according to the actual environment, so as to improve the processing accuracy

(2) allowable assembly error: wrong joint δ 1 < 2.0, butt clearance δ 2= 1.0, lap gap δ 3 < 1.5, T-shaped clearance < δ 4=1.5

(3) check the assembly accuracy and lag behind in tack welding

(4) the assembled components shall be numbered on the obvious parts with paint

4. Welding

(1) before welding, the welder should review the assembly quality and the cleaning environment of the welding area. If it is not suitable for the technical requirements, it should be repaired and qualified before welding

(2) when the groove welding of thick plates is stopped, the middle layer of the weld can be welded with ¢ 5 ¢ mm or ¢ 6 ¢ mm electrode depending on the environment

(3) in the process of arc welding, especially at the tack weld, the back gouging task should be done well, and the flawless weld metal can be completely cleaned out before welding

(4) observe the following criteria when welding

do not concentrate heat in one part, and try to separate evenly; Adopt the construction method of "the deformation caused by the first welding is reduced by the subsequent welding"; The construction of parallel welds shall be stopped at the same time along the same welding target as far as possible; Stop welding outward from the middle of the layout; Weld from the thick part of the plate to the thin part

(5) after welding, if cracks are found in the weld, the welder shall not deal with them privately, and shall report to the person in charge of welding to find out the notice

(6) the weld after welding must be completely broken of welding slag, spatter and overlap

(II) rust removal and anti-corrosion of steel components

in order to ensure the service life of the shaft drainage pipeline, fully demonstrate the investment benefits, and follow the design requirements of the shaft drainage pipeline device, the "arc spraying process" is selected to stop the anti-corrosion treatment of the shaft pipeline, stinger beam, stuck pipe beam, support and other metal components. This technology is advanced. This construction technology follows the general pretreatment → the smooth stop of arc spraying

1. Construction preparation

operate the 6m3 air compressor as the construction air source, and use the air pipe to replace the oil filter. One acrr/ac high-efficiency sand blasting machine, one set of compressed air filter processor, and one set of arc spraying equipment will be selected, which will be connected to form a fragment. When the power is connected, the rust removal of the workpiece can be stopped

2. General pretreatment

(1) the general pretreatment of the workpiece before spraying is a key link related to the success or failure of the spraying operation. The workpiece after pretreatment is a bright outline without oil, rust, clean and sufficient roughness. The first step of the general pretreatment is to remove the general oil, oxide skin, paint, soil and other dirt of the workpiece, and the method is sand blasting rust removal process

(2) the workpiece that has been derusted by sand blasting is basically clean and has a large outline as much as possible, which is very important for the effective contact between the coating and the workpiece. We can meet the above requirements by using the jet suction sandblasting machine to roughly roughen the workpiece. The compressed air used by the sand blasting machine is connected by the 6m3 air compressor, and the dry, oil-free air with a pressure of 0.6MPa is obtained through the compressed air filter processor. When the sand blasting is roughened, it is stopped in the semi enclosed sand blasting task shed, so that on the one hand, it is convenient for the sand material to be received and reused, on the other hand, it increases pollution. The operating staff must wear sanding clothes when doing homework, and stop strictly following the procedures, The included angle between the target of the abrasive radiation target and the workpiece should be controlled at 60 degrees. The interval from the sandblasting nozzle to the workpiece should be 100-300 mm. During sandblasting, the nozzle should be prevented from being perpendicular to the workpiece to prevent the abrasive from bouncing back to hurt people. The nozzle aperture used for sandblasting is ¢ 8 mm, and the abrasive is quartz sand with No. 30 gauge (particle size 1-2.5 mm). After sandblasting, the steel workpiece is roughly silver gray, uniformly roughened, and free of rust spots and other substances, The derusting grade meets the requirements of Swedish Sa2.5 standard

3. Arc spraying process

arc spraying zinc according to the requirements of the design and construction drawing of the shaft drainage pipeline device. After the workpiece is roughened, connect the arc spraying motor source, adjust the voltage, current and atomization gas source of the spraying machine, and stop the workpiece spraying work. Because the arc light generated during arc spraying is serious to the eyes, and the generated gas and dust are harmful to the human body, the operators must wear spraying clothes and dark glasses to stop protection. During spraying, the interval between the spray gun and the workpiece should be stable, and the walking speed should not be too fast or too slow. Evenly spray and crimp the last coating, and the sprayed workpiece should be painted with a layer of sealing paint to stop sheltering. During arc spraying corrosion prevention, the workpiece shall be stopped by classification until it is completely completed

4. After arc zinc spraying, apply one coat of epoxy asphalt primer, and start the oil pump to adjust the pointer to the zero position, and apply two coats of oxygen asphalt finish paint

5. During the processing of non-standard parts of the drainage pipeline of Suncun mine barrel and the derusting and corrosion prevention of steel components, close attention should be paid to the climate change. It is strictly forbidden to stop sandblasting and arc spraying in rainy days. If it must be stopped, the sandblasting process garden should be set up with a rainproof shed, and the arc spraying process should be placed in the internal skill class of the right and work shed. It is required that the spraying construction of workpieces qualified for derusting must be stopped within 2 hours

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