Means of protection against mechanical injury. Presentation on labor protection on the topic "protecting a person from the danger of mechanical injury and from dangerous factors of a complex nature" Personal protective equipment against mechanical injury

16.05.2020

The problem of injuries at work is one of the most acute problems facing the state and entrepreneurs in today's technogenic society. The risk factor is a serious organizational and psychological problem in the complex of measures for labor protection at work. Many machines and structures, technological processes should be considered as sources of increased danger to people. This is an inevitable by-product of scientific and technological progress. The definition of the technical aspect of risk is based on possible deviations of the parameters of technological processes and the reliability of equipment from normal, leading to unforeseen material consequences and human casualties. Among the technical causes of an accident at work, the causes associated with the insufficient reliability of production equipment, structures, devices or their elements occupy a special place, since most often they appear suddenly and, therefore, are characterized by high rates of injury severity.

The means of protection against mechanical injury include safety brakes, protective devices, automatic control and alarm systems, safety signs, systems remote control. Remote control systems and automatic signaling devices for dangerous concentrations of vapors, gases, dusts are most often used in explosive industries and industries with the release of toxic substances into the air of the working area.

Safety protective equipment are designed for automatic shutdown of units and machines when any parameter characterizing the operating mode of the equipment deviates beyond the limits of permissible values.

Thus, in case of emergency conditions (increase in pressure, temperature, operating speeds, current strength, torques, etc.), the possibility of explosions, breakdowns, and ignitions is excluded. In accordance with GOST 12.4.125-83, safety devices, by the nature of their action, are blocking and restrictive. Locking devices according to the principle of operation are divided into mechanical, electronic, electrical, electromagnetic, pneumatic, hydraulic, optical, magnetic and combined.

Restrictive devices according to their design are divided into couplings, pins, valves, keys, membranes, springs, bellows and washers. Blocking devices prevent a person from entering the danger zone or eliminate the dangerous factor during his stay in this zone. Especially great importance these types of protective equipment are attached to the workplaces of units and machines that do not have guards, as well as where work can be carried out with the guards removed or open. Mechanical interlock is a system that provides communication between the fence and the braking (starting) device. When the guard is removed, the unit cannot be braked and, therefore, put into motion. Electrical interlocking is used in electrical installations with a voltage of 500 V and above, as well as in various types technological equipment with electric drive. It ensures that the equipment is switched on only when there is a fence. Electromagnetic (radio frequency) blocking is used to prevent a person from entering the danger zone. If this happens, the high frequency generator supplies a current pulse to the electromagnetic amplifier and the polarized relay. The contacts of the electromagnetic relay de-energize the magnetic starter circuit, which provides electromagnetic braking of the drive in tenths of a second. Magnetic blocking works similarly, using a constant magnetic field. Optical blocking finds application in forging and pressing and machine shops of machine-building plants.

The light beam falling on the photocell ensures a constant current flow in the winding of the blocking electromagnet. If at the moment the pedal is pressed, the worker’s hand is in the working (dangerous) zone of the stamp, the fall of the light current on the photocell stops, the windings of the blocking magnet are de-energized, its armature is extended under the action of the spring, and turning on the press with the pedal becomes impossible.

Examples of limiting devices are elements of mechanisms and machines designed for destruction (or failure) during overloads. The weak links of such devices include: shear pins and keys connecting the shaft to the flywheel, gear or pulley; friction clutches that do not transmit movement at high torques; fuses in electrical installations; bursting discs in high-pressure installations, etc. Weak links are divided into two main groups: links with automatic restoration of the kinematic chain after the controlled parameter has returned to normal (for example, friction clutches), and links with the restoration of the kinematic chain by replacing weak link (for example, pins and keys). The operation of a weak link leads to a shutdown of the machine in emergency modes.

Brake devices are divided into:

by design - on shoe, disk, conical and wedge; according to the method of operation - manual, automatic and semi-automatic;

according to the principle of action - on mechanical, electromagnetic, pneumatic, hydraulic and combined;

by appointment - for working, reserve, parking and emergency braking.

Protective devices- a class of protective equipment that prevents a person from entering the danger zone. They also enclose working areas located at a height (forests, etc.). Constructive solutions for protective devices are very diverse. They depend on the type of equipment, the location of a person in the working area, the specifics of hazardous and harmful factors that accompany the technological process. In accordance with GOST 12.4.125-83, which classifies means of protection against mechanical injury, protective devices are divided: by design - into casings, doors, shields, visors, slats, barriers and screens; according to the manufacturing method - into solid, non-solid (perforated, mesh, lattice) and combined; according to the method of installation - on stationary and mobile. Examples of a complete stationary fence are the fences of electrical equipment switchgear, the casing of tumbling drums, the casing of electric motors, pumps, etc.; partial - fencing mills or the working area of the machine.

It is possible to use a movable (removable) fence. It is a device interlocked with the working bodies of a mechanism or machine, as a result of which it closes access to the working area when dangerous moment. Such restrictive devices are especially widespread in the machine tool industry (for example, in OFZ-36 CNC machines). vibration safety injury

Portable fences are temporary. They are used in repair and adjustment work to protect against accidental contact with live parts, as well as from mechanical injuries and burns. In addition, they are used at permanent workplaces of welders to protect others from the effects of electric arc and ultraviolet radiation (welding posts). They are most often performed in the form of shields 1.7 m high. The design and material of the enclosing devices are determined by the features of the equipment and technological process generally. Fences are made in the form of welded and cast casings, gratings, meshes on a rigid frame, as well as in the form of rigid solid shields (shields, screens). The dimensions of the cells in the mesh and lattice fencing will be determined in accordance with GOST 12.2.062-81*. Metals, plastics, and wood are used as fencing materials. If it is necessary to monitor the working area, in addition to grids and gratings, solid protective devices made of transparent materials (plexiglass, triplex, etc.) are used. Guards must be strong enough to withstand the loads from particles flying off during processing and accidental impacts by operating personnel. When calculating the strength of the fences of machines and units for processing metals and wood, it is necessary to take into account the possibility of flying out and hitting the fence of the workpieces being processed. The calculation of fences is carried out according to special methods.

Methods and means of protection against mechanical injury when working with process equipment and tools

To protect against mechanical injury, the following methods are used:

1. unavailability of dangerous objects for humans;

2. the use of devices that protect a person from a dangerous object;

3. use of PPE.

Protective devices must meet the following requirements:

1. prevent equipment contact with a person;

2. provide security;

3. protect from falling objects;

4. not create new dangers;

5. do not interfere.

Enclosing, safety, braking devices, automatic control and signaling devices, remote control are used to protect against mechanical injury to machines, mechanisms, and tools.

1. Enclosing devices are designed to prevent a person from accidentally entering the danger zone. They are used to isolate moving parts of machines, processing areas of machine tools, presses, impact elements of machines. Fencing devices can be stationary, mobile and portable. They are made in the form of protective: casings, visors, barriers, screens, doors. They are made from metals, plastics and wood. They can be both solid and mesh.

2. Safety (blocking) devices are designed to automatically turn off machines and equipment in case of deviation from the normal mode of operation, or if a person enters the danger zone. Safety devices can stop equipment or machines if a hand or other part of the body is inadvertently placed in a hazardous area.

There are the following main types of safety devices:

presence detection device (photoelectric, electromagnetic, electromechanical, pneumatic, mechanical);

retraction devices.

3. Braking devices are subdivided according to their design:

Well-shaped;

Disk;

Conical;

Wedge.

Brakes can be manual, foot, semi-automatic and automatic.

4. Automatic control and signaling devices are the most important conditions for safe and reliable operation of equipment.

Control devices - devices for changing pressure, temperature, static and dynamic loads and other parameters that characterize the operation of equipment and machines. The efficiency of their use is significantly increased when they are combined with signaling systems (sound, light, color, sign or combined). Automatic control and signaling devices are divided according to their purpose:

Informational;

warning;

Emergency.

By way of operation:

Automatic;

Semi-automatic.

5. Remote control devices most reliably solve the problem of security, as they allow remote control.

Remote control devices are divided into:

A. by design:

Stationary;

Mobile.

B. according to the principle of action:

Mechanical;

Electrical;

Pneumatic;

hydraulic;

Combined.

6. Safety signs can be warning, prescriptive and indicative and differ from each other in color and shape. The type of signs is strictly regulated by the state standard.

Safe working practices with hand tool

The organization of the workplace is of great importance in ensuring labor safety. When organizing a workplace, it is necessary to ensure:

1. convenient design and proper arrangement of work tables and workbenches, free access to workplaces is required, and the area around the workplace must be free at a distance of at least 1 meter.

2. a rational system for arranging tools, fixtures and auxiliary materials at the workplace.

To avoid injury when working with hand tools, you must be guided by right-handed safety:

1. When working with cutting and piercing tools, their cutting edges should be directed away from the body of the worker in order to avoid injury.

2. The fingers holding the processed object must be at a safe distance from the cutting edges, and the object itself must be securely fixed in a vice,

3. The position of the body of the worker must be stable. You can not stand on an unstable and oscillating foundation.

4. When working with a tool that has electric drive electrical safety requirements must be observed.

5. The worker must be dressed in such a way as to prevent parts of the clothing from getting on the edge or on the moving parts of the tool, more precisely, so that the sleeves of the clothes are buttoned up, otherwise the hand may be pulled under the cutting tool.

6. When processing large materials, it is necessary to have special screens, as well as goggles or a mask. Work clothes should be made of dense material.

Ensuring the safety of handling equipment

Safety during the operation of handling equipment and machines (PTM) is ensured by the following methods:

1. determination of the size of the danger zone of anti-tank guns;

2. the use of means of protection against mechanical injury from PTM mechanisms;

3. strength calculation of ropes and load-gripping devices (GZU);

4. determination of the stability of cranes;

5. use of special safety devices;

6. registration, technical examination and testing.

All newly installed load-lifting machines, as well as removable load-handling devices, are subject to technical examination before being put into operation.

Lifting machines in operation must be subject to a periodic partial survey every 12 months, and a complete one after 3 years.

test questions

1. What are the requirements for devices to protect against mechanical injury?

2. List the main types of protective devices.

3. How is the fencing of hazardous areas, and what are the types of fencing?

4. What types of safety (blocking) devices are used in production and how are they arranged?

5. List the emergency shutdown devices and explain how they work.

6. Explain the purpose of two-handed equipment control.

7. What additional methods and security enhancements are used in production?

8. List the basic rules for using a hand tool.

9. What methods are used to ensure the safety of PTM?

10. What safety devices are used on the PTM?

11. How and by whom is the registration, examination and testing of anti-tank equipment carried out?

Means of protection against mechanical injury Means of protection against mechanical injury include: safety devices; braking devices; protective devices; means of automatic control and signaling; safety signs; remote control systems. By the nature of the action, safety devices are blocking and restrictive. Locking devices prevent a person from entering the danger zone. Brake devices are divided into working reserve parking ...

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29. Means of protection against mechanical injury

Means of protection against mechanical injury include:

safety devices;
- braking devices;
- protective devices;
- means of automatic control and signaling;
- safety signs;
- remote control systems.

Safety protective equipment is intended for automatic shutdown of units and machines when any parameter characterizing the operating mode of the equipment deviates beyond the limits of permissible values. Thus, in emergency conditions, the possibility of explosions, breakdowns and ignitions is excluded. By the nature of the action, safety devices are blocking and restrictive.

Locking devices prevent a person from entering the danger zone. Particularly great importance is attached to these types of protective equipment at the workplaces of units and machines that do not have guards, as well as where work can be carried out with the guards removed or open. Examples of limiting devices are elements of mechanisms and machines designed for destruction or failure during overloads.

Braking devices are divided into working, reserve, parking and emergency braking.

Protective devices are a class of protective equipment that prevents a person from entering a dangerous area. Protective devices are used to isolate drive systems of machines and assemblies, workpiece processing areas on machine tools, presses, dies, exposed live parts, areas of intense radiation and areas for the release of harmful substances. Constructive solutions for protective devices are very diverse. They depend on the type of equipment, the location of a person in the working area, the specifics of hazardous and harmful factors that accompany the technological process.

Automatic signaling devices and remote control systems are most often used in explosive industries and industries with the release of toxic substances into the air of the working area.

The presence of instrumentation is one of the conditions for the safe and reliable operation of equipment. These are devices for measuring pressure, temperatures, static and dynamic loads, concentrations of vapors and gases. The efficiency of their use increases when they are combined with alarm systems.

Automatic control and signaling devices are divided into information, warning, emergency and response.

Information signaling is used to coordinate the actions of workers, in particular crane operators and slingers. The same signaling is used in noisy industries where voice communication is disrupted. Information signaling also includes schemes, pointers, inscriptions. As a rule, inscriptions are made directly on the equipment or in the service area on special displays.

Warning devices are designed to alert you to danger. Most often they use light and sound signals coming from various devices. Warning signaling, which is ahead of switching on equipment or supplying high voltage, finds great application. Warning signs include signs and posters "Do not turn on - people are working", "Do not enter" and so on. Usually pointers are made in the form of light panels with flashing backlight.

Safety signs differ from each other in shape and color. They can be prohibitive, warning, prescriptive and indicative.

In production equipment and in workshops, warning signs are used, which are a yellow triangle with a black strip around the perimeter, inside of which there is a black symbol. For example, in case of electrical danger, it is lightning; in case of danger of injury by a moving load, it is a load; in case of a risk of slipping, it is a falling person; in case of other dangers, an exclamation mark. The prohibition sign is a red circle with a white border around the perimeter and a black image inside. Mandatory signs are a blue circle with a white border around the perimeter and a white image in the center, while indication signs are a blue rectangle. Fire-extinguishing equipment indication signs have a red symbol on a white background.

The control of providing equipment with means of protection against mechanical injury and their serviceability is assigned to the chief mechanic of enterprises and mechanics of departments.

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Protection against mechanical injury

To protect against mechanical injury, two main methods are used:

* Ensuring the inaccessibility of a person to dangerous areas;

* the use of devices that protect a person from a dangerous factor.

Means of protection against mechanical injury are divided into:

* collective (SKZ;

* individual (PPE).

SCs are divided into:

* protective;

* safety;

* brake devices;

* automatic control and signaling devices;

* remote control;

* safety signs.

Protective devices.

Designed to prevent accidental entry of a person into the danger zone. They are used to isolate moving parts of machines, processing areas of machine tools, presses, impact elements of machines, etc. from the working area.

They may be:

* stationary;

* mobile;

* portable

They are made in the form of protective covers, doors, visors, barriers, screens.

Protective devices are made of metal, plastic, wood and can be either solid or mesh.

Working part cutting tools(saws, milling cutters, cutter heads, etc.) should be closed by an automatically operating guard that opens during the passage of the material being processed or the tool only to pass it.

Guards must be strong enough to withstand loads from flying particles of the processed material, collapsing processing tools, from the breakdown of the workpiece, etc.

Portable fences are used as temporary during repair and adjustment work.

Safety devices are designed to automatically turn off machines and equipment in case of deviation from the normal mode of operation or when a person enters the danger zone.

They are divided into:

* blocking;

* restrictive.

Blocking devices exclude the possibility of a person entering the danger zone.

According to the principle of action, they can be:

* mechanical;

* electromechanical;

* electromagnetic (radio frequency);

* photoelectric;

* radiation;

* pneumatic;

* ultrasonic, etc.

Photoelectric blocking is widely used, based on the principle of converting the light flux incident on the photocell into an electrical signal. The danger zone is protected by light rays. Crossing a light beam by a person causes a change in the photocurrent and activates the mechanisms for protecting or shutting down the installation. Used on subway turnstiles.

Radiation blocking is based on the use of radioactive isotopes. Ionizing radiation directed from the source is captured by a measuring and command device that controls the operation of the relay. When crossing the beam, the measuring and command device sends a signal to the relay, which breaks electrical contact and turn off the equipment.

Restrictive devices.

These are elements of mechanisms and machines designed for destruction (or failure) during overloads.

These elements include:

* shear pins and keys connecting the shaft with the drive;

* friction clutches that do not transmit movement at high torques, etc.

They are divided into two groups:

* elements with automatic restoration of the kinematic chain after the controlled parameter has returned to normal (for example, friction clutches);

* elements with the restoration of the kinematic connection by replacing it (for example, pins and keys).

Brake devices.

By design, they are divided into:

* shoe;

* disk;

* conical;

* wedge.

Most often used shoe and disc brakes.

An example of such brakes can be the brakes of automobiles.

Automatic control and alarm devices

Control devices are devices for measuring pressures, temperatures, static and dynamic loads and other parameters that characterize the operation of equipment and machines.

The efficiency of their use is greatly increased when combined with alarm systems.

Automatic control and alarm devices are divided into:

by appointment:

* information;

* warning;

* emergency;

P about the operation method:

* automatic;

* semi-automatic.

The following colors are used for signaling:

* red - forbidding;

* yellow - warning;

* green - notifying;

* blue - signaling.

The type of information signaling is various kinds of schemes, pointers, inscriptions.

Remote control devices (stationary and mobile) most reliably solve the problem of ensuring safety, as they allow you to control the operation of equipment from areas outside the danger zone.

Safety signs.

Their appearance is regulated by GOST R 12.4026-01.

They may be:

* forbidding;

* warning;

* prescriptive;

* index;

* firemen;

* evacuation;

* medical.

First aid for bleeding. There are arterial, venous and capillary bleeding. Blood from a gaping wound is poured out in a light red color rhythmically, in a pulsating stream with arterial bleeding, and a dark color in a continuous continuous stream with venous bleeding. Capillary bleeding - blood from damaged small vessels flows like a sponge.
When providing first aid, a temporary stop of bleeding is used.
A twist (tourniquet) is used only when simple and safe methods cannot stop the bleeding, and is used more often when bleeding from an amputated stump.
Victims with temporarily stopped bleeding should be urgently delivered to a surgical hospital in a horizontal position on a shield or stretcher.
First aid for traumatic bruises. In order to prevent hemorrhage, it is necessary to hold the cold at the site of the bruise, provide the affected organ with absolute rest and apply a pressure bandage. In case of bruises of the head, chest, abdomen, accompanied by severe pain and deterioration of the general condition, the victim must be urgently shown to the doctor.
Sprain or damage to the ligamentous apparatus of the joint occurs with sudden impulsive movements in the joint, significantly exceeding the limits of normal mobility in it, or may be the result of a direct blow to a tense tendon.
With a fracture, acute local pain is noted, which increases with the movement of the limb and the load on it along the axis, swelling and an increase in the circumference of the limb segment at the level of the fracture. Absolute signs of a fracture: deformation of the damaged segment and pathological bone mobility.
First aid consists in transport immobilization of the limb, most often with the help of splints made from improvised materials (boards, plywood strips, etc.).
First aid for wounds - protection of wounds from secondary contamination. The surrounding skin around the wound should be smeared twice with an alcoholic solution of iodine and a sterile dressing should be applied, avoiding touching the wound itself. Foreign bodies embedded in tissues should not be removed, as this may increase bleeding. Any washing of the wound is prohibited!
When drowning, the nature of assistance to the victim depends on the severity of his condition. If the victim is conscious, he needs to be calmed, take off his wet clothes, wipe his skin dry, change clothes; if consciousness is absent, but the pulse and breathing are preserved, the victim should be allowed to inhale ammonia, free the chest from tight clothing; to activate breathing, you can use the rhythmic twitching of the tongue.
In case of poisoning, the victim must be laid down with his head raised. Rinse the stomach with 1-2 liters of water, induce vomiting by pressing on the root of the tongue. An unconscious patient is strictly forbidden to wash the stomach. Water can be inhaled and cause death by suffocation. If the victim is not breathing or his breathing is oppressed, it is necessary to perform artificial respiration.

The greatest application for protecting a person from mechanical injury is found in protective and safety equipment, braking and blocking devices, automatic control and signaling devices.

Protective means of protection most common in industry. They prevent a person from entering the danger zone. All open moving and rotating parts of equipment located at a height of up to 2.5 m from the floor level, if they are sources of danger, must be covered with a solid or mesh fence. Guards can be complete, covering the traumatic unit as a whole, and partial, excluding access to the most dangerous parts of the equipment.

In most cases, the guards are stationary, but in metal forming machines and some types of machine tools, they can be movable, with the working bodies of the equipment blocked.

Guards close access to the danger zone only at the time of processing (for example, cutting down a workpiece). Perhaps the device of movable barriers with an individual drive. Movable protective devices with an individual drive are the most promising means of protection.

The design of the fence is most often a casing. In the cases of machines and mechanisms, as well as machine tools, they can be made in the form of a door that blocks access to gearboxes, gearboxes and other drive elements. Guards in the form of shields (including mesh ones) are widely used in robotic production (Fig. 11.59).

Portable shields are installed during repair and adjustment work to prevent unauthorized persons from entering the area of their implementation, for example, during welding, work in underground utility wells, and when repairing electrical installations in workshops.

Guards are made from metals and plastics. Wide application find net fences. When calculating the strength of fences used in the processing of metals and wood, it is necessary to take into account the possibility of flying out and hitting the fence with workpieces and cutting tools.

Safety devices can be of two types: restrictive and blocking.

Limiting devices are triggered when any parameter characterizing the operation of the mechanism or machines is exceeded. For example, shear pins and keys are activated when the permissible torque is exceeded, safety valves- when the working pressure is exceeded, stops - when the elements go beyond the tolerance

Rice. 11.59.

stimable limits in space. Thus, the modes of operation of the equipment are excluded, in which it is possible to injure a person.

There are safety limiting devices with automatic restoration of the kinematic chain after the controlled parameter has returned to normal, and devices that, after operation, require the equipment to be stopped and replaced. An example of the former are safety valves, friction clutches, pressure regulators, the latter are fuses for electrical installations, bursting discs of systems operating under pressure.

Brake devices are divided into four groups:

1) according to the design - on shoe disc, conical and wedge;
2) actuation method - manual, automatic and semi-automatic;

3) the principle of operation - for mechanical, electromagnetic, pneumatic, hydraulic and combined;
4) purpose - for working, reserve, parking and emergency braking.

Brakes play an important role in ensuring the safe operation, repair and maintenance of process equipment, allowing you to quickly stop shafts, spindles and other elements that are potential sources of danger. In addition, they serve to stop or brake the load in hoisting and transport machines. We especially note that all types of traumatic equipment have emergency braking systems in emergency situations. They are mandatory in automatic lines. In especially dangerous cases, reserve braking systems are provided.

Parking brakes are used in hoisting cranes operating on a rail track, which excludes their movement with a significant wind load. This eliminates the possibility of overturning the crane due to loss of stability.

In equipment, disc and shoe brakes are most often used.

A special case of braking devices are speed controllers, which limit the speed of rotation of the shafts of internal combustion engines and turbines, as well as the speed of lowering loads.

Stops and catchers are widely used on hoisting and transport machines to hold the lifted load, as well as in some mechanisms to prevent the reverse movement of rotating elements.

Locking devices exclude the possibility of a person entering the danger zone or eliminate the dangerous factor for the duration of the person's stay in this zone.

Mechanical interlock is a system that provides communication between the fence and the braking (starting) device. For example, to remove the guard of the crank mechanism, it is necessary to slow down and completely stop the mechanism drive, which is carried out by turning off the electric motor.

With the guard removed, the unit cannot be started. According to this principle, the doors are blocked in the premises of the test benches, as well as in other, especially dangerous premises, in which the presence of people during the operation of the equipment is prohibited.

Automatic control and alarm devices are also one of the ways to protect a person from mechanical injury. Availability of instrumentation is one of the conditions for safe and reliable operation of equipment. These are devices for measuring pressures, temperatures, static and dynamic loads and other parameters, the excess of which can lead to an accident. The effectiveness of control devices is increased when combined with alarm systems.

Informative alarm finds application in many technological processes, as well as on test benches. Informative signaling is also used to coordinate the actions of workers, in particular crane operators and slingers.

Devices warning signal designed to alert you to danger. Most often, they use light and sound signals from various instruments that record the progress of the technological process, including the level of hazardous and harmful factors. Sirens or bells are used for sound signaling.

The signaling, which is ahead of the switching on of the equipment, finds great application. It is provided for in industries where people can be in the danger zone before starting work (engine test sites, automatic assembly lines, foundries, etc.). Signaling includes signs and posters “Do not turn on - people are working”, “Do not enter», "Do not open - high voltage" etc. Inscriptions indicating permissible load must be located directly in the service area of machines and units. On rotating and moving devices for mechanized clamping of workpieces of metal-cutting machine tools, there must be clearly made indelible inscriptions indicating the maximum permissible characteristics of their movement, in which the operation of the machine remains safe. It is desirable to carry out pointers in the form of light panels with a time-varying (flashing) backlight.

A subspecies of warning signaling is signal coloring (marking). Traumatic elements of equipment are distinguished by alternating (at an angle of 45 ° to the horizontal) stripes of yellow and black. Enclosing barriers and elements of buildings are also painted (Fig. 11.60).

When platforms (galleries) are located at a height of less than 2.2 m from the floor, their side surfaces are painted in yellow signal color. On machines, the reverse sides of the doors of the niches for electrical equipment, as well as the surface of the chip flow, are painted red. Signal painting, like the painting of pressurized installations and systems, is an example of color signaling. Signal colors are widely used in industry. In table. 11.31 presented semantic meanings and areas of application of signal colors and their corresponding contrast colors.

Safety signs are standardized GOST 12.4.026-02. They differ in shape and color. Geometric

Rice. 11.60.

a- fences; b - dimensions of transport openings; in- difference in the plane of the floor; G - parts of lifting equipment; d - vehicles sky forms, signal colors and semantic meanings of the main safety signs are given in Table. 11.32.

Table 1131

Meanings, areas of application of signal colors and their corresponding contrasting colors

Signal	semantic meaning	Application area	Contrasting
	Immediate danger
		Identification of immediate danger
	emergency or dangerous situation	Message about emergency shutdown or emergency condition of equipment (technological process)
	Fire equipment, fire protection equipment, their elements	Designation and determination of the location of fire equipment, fire protection equipment, their elements
	Possible danger	Designation of possible danger, dangerous situation
		Warning, danger warning
	Safety, safe conditions	Message about the normal operation of the equipment, the normal state of the technological process
	the rescue	Designation of the evacuation route, first aid kits, cabinets, first aid equipment
	Prescription to avoid danger	Requiring mandatory action to ensure safety
	indication	Allowing certain actions

Table 1132

Geometric shapes, signal colors and semantic meanings of the main safety signs

	Geometric	Signal	semantic meaning
prohibition signs			Prohibition of dangerous behavior or action
warning signs			Possible danger warning. Caution. Attention
Mandatory signs			Prescription of mandatory actions to avoid danger
Fire safety signs			Designation and indication of the location of fire protection equipment, their elements
Evacuation signs and signs for medical and sanitary purposes			Designation of the direction of movement during evacuation, rescue, first aid in case of accidents or fires. Lettering, safety information
Directive signs			Permission. Instruction. inscription or information

Operational safety of handling equipment. Safety during the operation of handling equipment and machines is ensured by the following methods:

determination of the size of the danger zone of anti-tank guns;

- strength calculation of ropes and load-handling devices;
- determination of the stability of cranes; the use of means of protection against mechanical injury by PTM mechanisms;
- the use of special safety devices;
- registration, technical examination and testing of GGGM and GZU.

The operation of cranes is determined by the regulatory document PB 10-382-2000 "Rules for the design and safe operation of cranes".

The size of the danger zone PTM depends on the lifting height of the load and the length of the path of movement of the ATM with the load. Circle radius R, within which the load can fall, is determined by the formula

where g s- crane boom outreach from its axis of rotation (for overhead and gantry cranes r c = 0); /,. - the largest linear dimension of the load (when lifting long loads vertically, their departure is associated with a fall to the full length); H - lifting height.

Calculation of ropes for strength carried out according to the formula

where TO - safety factor of the rope at breaking force; R- permissible breaking force of the rope, N, determined according to the certificate for the rope; S- maximum rope tension (excluding dynamic loads), N.

Value To is determined by the rules of Rostekhnadzor and depends on the type of rope and anti-tank gun, its operating conditions. So, for industrial cranes, depending on the operating conditions of the rope K = 3.5n-6, for freight elevators without conductor K = 8-IZ, for freight elevators with a conductor and passengers K= 9-I5.

For protection against mechanical trauma

PTM drive mechanisms (gear, chain, worm gears, shafts of PTM mechanisms, couplings, drums, running wheels, etc.) use means similar to the means of protection used for process equipment. First of all, fences are used to protect a person from injury.

To special safety devices PTM include load limiters. They automatically disable the lifting mechanism for loads that exceed the limit value by more than 10%. In jib cranes with variable lifting capacity, depending on the reach of the boom, apply load limiters, taking into account not only the mass of the lifted load, but also the magnitude of the boom. There are many types of limiters, differing in principle of operation and design.

Anti-theft devices are designed to keep a crane operating in the open air from spontaneous movement along the rail track under the influence of wind. The main element of anti-theft devices are rail clamps (rail clamps), by means of which the crane is manually or automatically fixed to the rails.

Other special safety devices are also used, such as blocking the hatch and cab doors in overhead cranes; slew limiters on tower cranes, tilt meters on mobile cranes, skew limiters on overhead cranes, etc.

Such load gripping devices as hooks, electromagnetic washers, grabs, pickups and grips (Fig. 11.61) are especially critical parts of the PTM and are made to fit the cargo moved with their help. When using them, it is necessary to periodically monitor the condition of the working surfaces (wear, absence of cracks and defects).

Registration, technical certification and testing of PTM and GZU is the most important method of providing material handling equipment and material handling machines. The safety of PTM is supervised by Rostekhnadzor. Registration of objects where cranes are operated must be carried out in accordance with

Fig. 11.61.

a- hook; b- electromagnetic washer: 1 - electromagnet,

2 - frame; in- grab; where - pincers for shafts, ingots, rolls

in accordance with the Rules for the registration of objects in the State Register of Hazardous Production Facilities, approved by Decree of the Government of the Russian Federation of November 24, 1998 No. 1371. Each load-lifting machine manufactured by the manufacturer must be accepted by the technical control department and provided with a passport, installation and operation instructions and other technical documentation provided for by GOST or TU. Prior to commissioning, the lifting machine must registration with the bodies of Rostekhnadzor, who issue permission to put it into operation. Registration of cranes in the bodies of Rostekhnadzor is carried out upon a written application of the owner and the passport of the crane. The load-lifting machine is subject to re-registration after the reconstruction of the machine, repair, transfer of the machine to another owner, rearrangement to a new location.

All newly installed lifting machines, as well as removable load gripping devices, before being put into operation, are subject to technical certification. Primary examination is carried out by the technical control department of the manufacturer before sending the cranes to the consumer. Hoisting machines in operation must be subject to a periodic partial survey every 12 months, and a complete one after three years. Infrequently used machines (e.g. cranes serving industrial premises only during repair) are subject to a full technical examination after five years.

During a full technical examination, the load-lifting machine is subjected to inspection, static and dynamic tests; with a partial technical examination - only inspection. During the inspection, the reliability of each unit and element of the machine is established, the degree of wear of ropes, chains, hooks, gear and worm gears, brakes, control devices and other devices, the operability of safety devices and devices, the fastening of ropes, the presence and serviceability of grounding and electrical interlocks, the condition fences, railings, stairs, etc.

The static test of a hoisting machine is intended to check its strength as a whole and the strength of individual elements. At jib cranes, load stability is checked under a load that is 25% higher than the nominal one. The test of jib cranes is carried out at the maximum and minimum outreach in the position corresponding to the least stability of the crane, while the load rises to a height of 100-200 mm. The crane is considered to have passed the test if the lifted load does not fall to the ground within 10 minutes, and when inspecting the crane and load gripping devices, no cracks, deformations or other damages are found.

A hoisting machine that has passed the static test is subjected to a dynamic test in order to check the operation of mechanisms, brakes, and safety devices. During dynamic testing, the mass of the load must exceed the nominal by 10%.

Requirements for operators of means of transport and PTM.

When operating vehicles and anti-tank vehicles, it is necessary to ensure:

Compliance of the operator's qualification with the level of requirements for the safe operation of anti-tank guns;

testing operators for their professional suitability before starting a specific type of activity;

Medical control of the operator's condition before the start of his interaction with the technical system.