The management of safe and civilized production includes oil leakage, water leakage, steam leakage, smoke leakage, ash leakage, coal leakage, powder leakage and gas leakage, which is what we call “running, emitting, dripping and leaking”. Today, we summarize some preventive measures of “running, emitting, dripping and leaking” for reference.
I preventive measures for water and steam leakage of valves.
1. All valves must be subject to different levels of hydrostatic test after entering the plant.
2. Valves that need to be disassembled for maintenance must be ground.
3. In the process of maintenance, it is necessary to carefully check whether the packing is added and whether the packing gland is tightened.
4. Before the installation of the valve, check whether there are dust, sand, iron oxide and other sundries inside the valve. If there are any of the above sundries, they must be cleaned before installation.
5. All valves must be equipped with gasket of corresponding grade before installation.
6. When installing the flange door, the fasteners must be tightened. When tightening the flange bolts, they must be tightened in a symmetrical direction in turn.
7. In the process of valve installation, all valves must be installed correctly according to the system and pressure, and random and mixed installation is strictly prohibited. All valves must be numbered and recorded according to the system before installation.
II Precautions for leakage of pulverized coal.
1. All flanges must be installed with sealing materials.
2. The areas prone to powder leakage are the coal valve at the inlet and outlet of the pulverizer, the coal feeder, the manufacturer’s flange, and all parts with flange connection. For this reason, all parts of the equipment of all manufacturers that are willing to leak powder shall be comprehensively inspected, and those without sealing materials shall be added twice, and the fasteners shall be tightened.
3. The following measures shall be taken for the leakage of pulverized coal at the welded junction of pulverized coal pipe.
3.1 before welding, the welding area must be carefully polished to metallic luster and the groove required for welding.
3.2 before butt joint, the butt joint clearance must be reserved and forced butt joint is strictly prohibited.
3.3 welding materials must be used correctly, and preheating must be carried out as required in cold weather.
III Preventive measures for oil system leakage and oil leakage.
1. During the installation of oil pipeline, all flange joints or union joints with screw thread must be equipped with oil resistant rubber pad or oil resistant asbestos pad.
2. Leakage points of oil system are mainly concentrated on flange and union with thread, so bolts must be tightened evenly when installing flange. Prevent leakage or looseness.
3. In the process of oil filtering, the maintenance personnel must always stick to the work post, and it is strictly prohibited to leave the post and cross the post.
4. Stop the oil filter before changing the oil filter paper.
5. When installing the temporary oil filter connecting pipe (high-strength plastic transparent hose), the joint must be bound firmly with lead wire to prevent the oil from jumping off after the oil filter runs for a long time.
IV. prevent the equipment and pipe fittings from foaming, emitting, dripping and leaking, with the following preventive measures:
For flange sealing gasket above 1.2.5mpa, metal winding gasket shall be used.
2.1.0mpa-2.5mpa flange gasket shall be asbestos gasket and painted with black lead powder.
3.1.0mpa water pipeline flange gasket shall be rubber gasket and painted with black lead powder.
4. The packing of water pump shall be Teflon composite packing.
5. The asbestos rope used in the sealing parts of the smoke and air coal pipes shall be twisted and added to the joint surface smoothly at one time. It is strictly prohibited to add it forcefully after tightening the screws.
V. the following measures shall be taken to eliminate the internal leakage of the valve: (the following measures shall be taken to prevent the leakage of the valve)
1. Install the pipeline, clean the iron oxide scale and the inner wall of the pipeline without sundries, and ensure that the inner wall of the pipeline is clean.
2. Ensure that the valves entering the site must be subject to 100% hydrostatic test.
3. All valves (except the inlet valve) shall be disassembled for inspection, grinding and maintenance, and records and marks shall be made for traceability. Important valves shall be listed in detail for secondary acceptance, so as to meet the requirements of “stamping, inspection and recording”.
❖ if it is missed, why?
(1) the contact between the opening and closing parts and the two sealing surfaces of the valve seat;
(2) the fitting position of packing, stem and stuffing box;
(3) connection between valve body and bonnet
The former leakage is called internal leakage, that is to say, the valve is not tightly closed, which will affect the ability of the valve to cut off the medium. The last two leaks are called leakage, that is, the medium leaks from the inside to the outside of the valve. Leakage will cause material loss, environmental pollution and even accidents.
Post time: Dec-04-2019