Three "one" for mine safety management

Mine safety production is a complex, rigorous and meticulous system project. If there is a problem in any link, it will cause property damage, and it will lead to mine damage. According to the practice of mine production for many years, the author believes that the whole process of mine safety production from excavation, mining to mining must start from the basics and focus on three “one” and four “roads” (electric lines, roads, wind roads and Management of waterways) (This article only elaborates on three "ones", and four "roads" look forward to Syria).

The three "ones" refer to "one board, one explosion, one rope", that is, the safety management of the roof, explosives, and wire rope. The roof management roof (including the chip) accident is the highest accident rate in mining enterprises, and is also the primary supervisory responsibility of mine safety management personnel and mine safety supervision departments. In order to avoid the roof falling and the gang, in addition to strict implementation of the backward mining regulations, reliable support should also be taken to solve the problem.

I. Mining reserve pillar support

The edge of the security pillar left in the mine is generally 6m and cylindrical, which is the most effective way of support. If the top plate is not stable, the column diameter can be left large and the column spacing can be reduced. Between the top plate and the security pillar, when the roof has a broken belt, it can be supported by an artificial slurry column (1 column or several columns). In the case that the roof is very unstable and fragile, the safety pillar should increase the diameter of the pillar and distribute it irregularly to ensure the safety of the partially broken roof. If the stope has a large area of ​​cracks, it can also be supported by bolts. The method is simple and the cost is low.

In addition, when security management personnel enter the mining site, they should pay close attention to the roof and the gangs. If you want to knock off the pumice at any time, you must immediately remove the pumice . If you need support, you must arrange the support immediately. Whether it is broken roof or piece help, we must fight for time and prevent it first. For individual roofs that are obviously cracked and unable to move, they can not be paralyzed. They can be broken into the gap with dry wooden wedges to observe the changes for future processing.

Second, the bolt spray support

Bolt shotcrete support is mainly suitable for large section, top rock stability and as a long-term use of the wellbore wall or larger diverticulum in the shaft and the support when installing larger facilities or other equipment.

The bolt spray support should be specially designed. The distance between the spray anchor working face and the heading face, the bolt type, the angle, the thickness and strength of the spray should be specified in the design. The eye hole of the mortar anchor must be cleaned and filled with filling; the anchor should be tested for tensile force, the thickness and strength of the spray should be checked, and the anchoring force test should be carried out under the well; the bolt of the anchor must be tight Attach the lane wall and tighten with a nut.

When handling the clogging of the injection pipeline, the lance must be facing downwards and not allowed to face the personnel; when spraying and anchoring in the loosely broken rock formation, the advanced anchor must be used to carry out the pre-protection; the spray anchoring operation is carried out in the dynamic pressure roadway. when, anchor and method for metal mesh combined support must be adopted; it is sprayed when the anchor job, you must have a pre-made waterproof work in tricking the roadway. Spray protection should be carried out with personal protective equipment and good ventilation and lighting.

  Third, wooden bracket support

The wooden bracket support is mostly used for temporary broken roof and rupture support in temporary roadway or roadway.

When supporting with wooden brackets, the pits of decay, boring, soft wood, birch, and splitting shall not be used. If it is used as a permanent bracket, it shall be treated with anti-corrosion treatment; after the wooden bracket is erected, the wooden wedge shall be used to place the beam near the joint. When the wooden bracket is trapezoidal symmetrical, the gap between the top plate and the two gangs must be tightly packed, and the joints of the beam and the column must be fixed with the dowels; the brackets close to the working surface should be nailed, Stretching, struts and other reinforcement; found that the slant leg skew, fracturing, beam and column fracture (commonly known as "broken beam and folding column") and pit wood decay should be replaced and repaired in time; the depth of the column nest should be no less than 30mm in hard rock. In soft rock, it should be no less than 100mm. It is forbidden to hit the column on the pumice stone.

Fourth, wooden pillar support

The wooden pillar support is the way in which a small part of the rock in the roadway or stope is split without the need for wooden support.

When supporting with wooden pillars, one or more wooden pillars can be supported by the roof and the floor sporadically. The height of the support should not be too high, generally less than 2m, and the diameter is more than 16cm, depending on the situation; The temporary support of the protection is suitable for the specific construction process; the wooden pillars must be vertically topped and tamped when supporting; when the roof is loose and easy to slide, the vertical direction should be 3°~10°. Yingshanjiao (or back mountain corner) support, to ensure that the roof is just perpendicular to the force after the sliding of the roof; before the soft top and bottom support, the appropriate thickness of the cushion should be added at the top of the column and the bottom of the column (commonly known as "wearing a hat and wearing a hat") After the folding column, it must be replaced. Before the replacement, it should be prepared according to the situation. Generally, temporary support is provided next to it. The state of blasting goods management has strict regulations on the production, storage, transportation, sale, purchase and use of blasting articles, such as "Safety Regulations for Metallurgical Mine Explosive Production" and "Blasting Safety Regulations". In addition to carefully managing the blasting items, the management personnel of mining enterprises must also supervise the use of blasting items.

(1) The blasting operation personnel must be served by the blasting personnel who have passed the examination and hold the "Blaster's Operation Certificate" issued by the county and city public security bureau. In addition, the blasting personnel shall be regularly reviewed and found to be unsuitable for continuing the blasting operation. The "Cleaner's Work Permit" shall be withdrawn.

(2) The enterprise must establish a strict blasting material retreat system and loss handling methods, and establish a blasting material destruction system in strict accordance with the Regulations on the Administration of Civil Explosives.

(3) When the workers in the well are exposed to the blasting materials, they must wear cotton or antistatic overalls.

(4) Blasting personnel (including blasting, drug delivery, and charging personnel) must be familiar with the performance of the blasting materials.

(5) In the underground blasting operation, the system of “one gun and three inspections” shall be strictly implemented.

Check before shooting. It is mainly to check whether the stacking of gravel and debris before the tunneling face (or stopway) prevents the operator from quickly withdrawing from the job site, and whether the roof support needs reinforcement. At the same time, it is necessary to tell other operators in the adjacent working face to do the evacuation work.

Charge and plug filling process inspection. Before charging, the rock dust in the blasthole must be removed, and then the medicine roll should be gently pushed in with wooden or bamboo gun sticks. The medicine rolls must be in close contact with each other and must not be bumped or tamped when pushed in.

After the charge, the blasthole sealant is applied with water cannon mud. The remaining blastholes outside the water cannon are sealed with clay or non-combustible mortar. It is strictly forbidden to use flammable materials or block materials for the mud. It is strictly forbidden to shoot the blasthole without sealing mud, insufficient mud or false. Humus soil, grass root and other materials can not be used as blasthole plug filler. Before the gun is fired, arrange a special person to do the safety alert work. If necessary, set a warning sign (line).

Check after shooting. In the case of good ventilation, the gun can be re-entered into the work surface after 30 minutes; if the ventilation is not good, the time to enter the work surface should be extended. When entering the work surface, it is necessary to confirm whether it is completely detonated, whether there is a dumb gun, whether there is excessive collapse after the blasting, whether the roof, the piece and the support are damaged; when entering the work surface, you need to knock on the top, remove the pumice, strengthen the branch. Protection; the air quality of the working surface is not good, and the dust-killing effect of the water cannon is also sprayed with water to remove dust. Wire rope management mines should pay special attention to the safety factor of the safety protection devices used in the wire ropes, safety ropes and lifting equipment when upgrading personnel, ore or other materials.

1. Shaft lifting

The main point of prevention of shaft lifting (human and material) is to prevent over-rolling (docks), cans, broken ropes, and rope knots. The lifting of the cage must comply with the prescribed number of people. The effective area occupied by each person entering the tank shall not be less than 0.18 m ² . When the number of persons exceeds the specified number, the hook work must be stopped. Tank doors or cans must be installed in the cage. The height of the tank door or can curtain should not be less than 1.2m. The tank door must not be opened and the door shaft must be protected from off. A car stop must be installed in the cage of the upgraded mine car; a single rope lifting cage for lifting personnel and materials must be equipped with a reliable fall arrester.

When the cage is lifted, the safety door of each middle section of the lane must be interlocked with the tank position and the lifting signal, that is, the safety door can be opened after the cage is in place and the signal is issued; the safety door is not closed, and only the leveling is adjusted (refer to adjust the cage to the vertical direction) After the safety door is closed, the level signal can be changed within the horizontal range and the signal can be changed, but the driving signal can not be issued; after the safety door is closed, the driving signal can be issued; after the driving signal is issued, the safety door cannot be opened. The sway should be set at the wellhead, the bottom of the well and the middle transport lane. It should be interlocked with the stop position of the cage, the car stop and the lifting signal system. That is, the cage is not in place, the cradle cannot be placed, and the swayer cannot be opened. Lift up, the car stop is not closed, and the driving signal cannot be sent.

2, inclined well lifting

The main point of prevention of inclined shaft lifting is to prevent the rope from being broken and unhooked, and the main measure is “three slopes at one slope”, that is, in the upper yard close to the slope point, it must be installed to prevent unconnected vehicles from sliding into the inclined lane. The car-stopper; at the location slightly below the length of the train at the point of the slope, it is necessary to provide a car bar that can prevent the unconnected vehicle; in the middle and lower part of the inclined shaft, it must be installed to stop the running rope and the decoupling vehicle. Anti-sports car device.

When the inclined shaft is lifted, it is forbidden to walk the hook and walk on the transport lane. At the same time, the safety rope must be hung, and the lower yard of the inclined shaft must be sheltered in a safe place.

3, set the protection device

Whether it is a shaft or inclined shaft lift, the hoist winch or hoist must be equipped with a depth indicator, emergency brake and anti-roll protection.

The over-roll height of the shaft lift shall comply with the following requirements:

When the lifting speed is less than 3m/s, the over-roll height is not less than 4m;

When the lifting speed is less than 6m/s, the over-roll height is not less than 6m;

The lifting speed is 6~10m/s, and the over-roll height is not less than the lifting height of the maximum lifting speed;

When the lifting speed is greater than 10m/s, the over-roll height is not less than 10m.

Inclined well lifting depends on the situation, generally more than 2m out of the vehicle platform can automatically power off (automatic contact stroke switch power off), safe braking.

The speed of the inclined well lifting container shall not exceed the following value:

When the length of the inclined well is less than 300m, the lifting speed shall not exceed 3.5m/s;

When the length of the inclined well is greater than 300m, the lifting speed shall not exceed 5m/s.

4, single rope lifting connection

When lifting a single rope, the rope and the lifting container must be connected by a peach ring. The wire rope is threaded from the flat side of the peach-shaped ring, and is fastened with the main rope by not less than 5 rope cards, and the spacing is 200-300 mm, and then the inspection circle is further observed.

5. Establish an inspection system

The hoisting wire rope must be inspected once a day, and the balance wire rope and the anti-dropper brake rope should be inspected at least once a week.

When the wire rope is subjected to violent pulling force such as a can, sudden stop, etc., it must be stopped immediately for inspection; for a section that is more susceptible to damage and rust, it should be parked for detailed inspection; the protruding part of the broken wire should be cut off during inspection, and the inspection result should be recorded. Wire rope inspection record.

When the ratio of the broken wire area to the wire rope cross section of the various strands of wire strands reaches the following values, it must be removed or replaced: the wire rope for the lifter is 5%; the wire rope for the lifting material, the balance wire rope, the fall prevention The brake rope is 10%; the tank rope is 15%. When the diameter reduction calculated based on the nominal diameter of the wire rope reaches the following values: 10% for the hoisting wire rope or brake wire rope; 15% for the wire rope; or when the wire rope is severely distorted, it must be removed or replaced. .

When lifting the wire rope, when the drum is wound in multiple layers, the safety condition of the wire rope from the lower layer to the upper part of the upper layer (corresponding to the circumference of the 1/4 rope) should be checked frequently, and the number of broken wires should be counted. The newly installed or overhauled fall arrester shall be tested once every 6 months without decoupling, and once a year for the decoupling test, the fall arrester and the transmission part must always be in a flexible state.