Special safety technical measures for ash chute

2022-06-24
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Special safety technical measures for using ash chute to slide ash

456 the net diameter of the air shaft is 7.6m, the net section is 45.3m2, the design elevation of the wellhead is +1360.00m, the full depth is 710.5m, and the freezing depth is 689m. At present, the ash chute is used for pouring concrete, and then it is poured into the formwork after secondary mixing. In order to better ensure safety and quality, this special safety technical measure is specially prepared

I. material selection:

the selected materials are selected according to volume V of well construction atlas, and the specifications are as follows:

flange: 8-inch plate * 20mm thick

pipe clamp: 60mm*10mm

bolt: Ф 20mm its tubular elastic structure is the common structural feature of many organs *70mm

steel pipe: φ 200*8mm

II. Selection and calculation of suspension wire rope, car stabilizing, suspension crown wheel and pipe clamp for ash chute:

1 Wire rope selection calculation

(1) wire rope suspension load

q0=q1+q2+q3+q4+q5=44885kg

then each wire rope suspension load: q0=q0/2=16942.5kg

where:—— φ 219 dead weight of 7.5mm steel pipe, =700 39.12=27384kg

-- weight of flange, clamp, bolt and nut, 2583kg

q3 -- weight of concrete in pipe, 3600kg

q4 -- weight of terminal clamp, 60kg

q5 -- weight of signal cable, cable clamp, bolt and nut. Q5=258kg

(2) calculation of weight per unit length of steel wire rope

where: - nominal tensile strength of steel wire rope, taking σ B=1770mpa

-- safety factor of steel wire rope, ma=5

through the above calculation, 18 7+fc- type steel wire rope (gb/t) is selected, the total minimum steel wire breaking force is qd=109598kg, and the weight per unit length is =5.63 kg/m

(3) check calculation of safety factor of steel wire rope

2. Select a stable car

maximum load of steel wire rope: q=16942.5+5.63 730 = 21052.4kg

select a 2jz-25/1300a stable car

3. Selection of suspension crown wheel

dtl ≥ 20ds=20 38=760mm (d wire rope diameter)

dtl ≥ 300 δ= 300 2.6=780mm ( δ by "The cooperation with BASF is very beneficial to HP (the thickest steel wire diameter)

mzs2.1.05/type double groove suspension crown wheel is selected to meet the requirements.

4. The pipe clamp is selected according to volume V of well construction atlas.

III. use the construction scheme of ash chute and step

2.1 construction scheme:

the concrete is made by the wellhead mixing plant. The concrete made by the mixing plant is placed in the sealing disk storage bin, and then passed through the chute The ash pipe is conveyed to the upper hanging plate, and then it is put into the mold through four conveying hoses after secondary mixing

2.2 construction steps:

during shaft excavation: when concrete pouring is required for each certain section of construction height

1. All holes at the wellhead shall be sealed tightly, and the ash chute shall be transported to the wellhead

2. Lock one end of the ash chute with a stirrup and then slowly lift it with a small winch at the wellhead. Slide the other end with a hemp rope and then pull it to a certain height

3. Connect it with the next section of ash chute with bolts and tighten it, and then fix the ash chute on the hanging steel wire rope with a pipe clamp

4. The connected ash chute slowly drops to the required height

5. After the ash chute is set, place the storage bin on the ash chute

6. Notify the working face to wash the ash chute with ground water after all are ready

7. After the ash chute is scoured and confirmed to be correct, the ash shall be poured, and the special signal shall be used during the pouring

during lining the inner wall of the shaft: when it is necessary to pour the next section of height after pouring a certain section of height

1, use a special signal to contact to stop ash discharge

2. Contact the working face to wash the ash chute

3. Remove the storage bin above the ash chute

4. Lock one end of the ash chute with the stirrup on the small winch

5. Contact the central control room to slowly lift the ash chute to a certain height

6. The steel wire rope of the small winch is stressed, and the bolts and pipe clamps connecting the ash chute are removed

7. The removed ash chute shall be lifted away from the wellhead by people, and then transported to the designated place by forklift and placed neatly

8. After removing a section of ash chute, lower the ash chute to a certain height

9. After the ash chute is completed, the storage bin shall be seated on the ash chute again

10. Inform the working face that the ash can be discharged, and use special signal to contact during the ash discharge

IV. safety precautions

1. The whole process must be under the unified command of a specially assigned person

2. The holes and gaps of the ash chute and the sealing disc must be sealed tightly each time, and the sundries must be cleaned to prevent falling objects from injuring people

3. The signals used at the wellhead, winch room and working face must be intact

4. The construction personnel on the hanging tray must wear the safety belt, and the safety belt must take root firmly

5. Tools and materials required for construction must have ropes

6. Personnel entering the well must abide by various rules and regulations

7. If the flame retardant is a high molecular synthetic material booster ash for a long time, and then the ash is discharged again, the pipeline must be washed with clean water

8. Pipe clamps and bolts used in construction must meet relevant requirements

9. Special signals must be used and kept intact during construction

10. Attachment: safety technical measures for replacement of ash chute. Blockage scheme and treatment measures for ash chute

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