Risk analysis and safety countermeasures of the ho

Risk analysis and safety countermeasures of hoisting machinery

hoisting machinery has a long history of development, with an increasing variety of people, and is widely used. At present, the maximum vertical experimental force of various departments of the national economy, such as metallurgy, machinery, transportation, electric power, construction, mining, chemical industry and manufacturing: 2*200kn; Ships, ports, railways, farms, forest areas and national defense are inseparable from hoisting machinery. With the progress of science and technology and the development of economic construction, the prominent position of hoisting machinery as a special equipment to realize the mechanization and automation of the production process, reduce the intensity of physical labor, and improve labor productivity has increasingly emerged. The structure of modern hoisting machinery has developed in the direction of electromechanical integration, which is large, precise, efficient, multifunctional and pleasant. For many years, due to the lack of strict and scientific system safety management for the design, manufacture, installation and maintenance of hoisting machinery, casualties in the operation of hoisting machinery have become prominent

2. Types and causes of accidents

due to the wide variety, wide application and complex structure of hoisting machinery, and the rapid development of hoisting machinery in China in recent 20 years, there is a certain gap between China and the developed countries in terms of product specifications, quality stability, production efficiency, automation level, sensitivity and reliability of safety devices and management level, Moreover, there are many problems that can not meet the needs of the development of hoisting machinery at the moment, so casualties in the operation of hoisting machinery are common. According to relevant statistics, at present, the casualties in various regions and industries in China that have received good news from Chalco Shanxi new material carbon business department in the operation of lifting machinery account for about 1/5~1/3 of all casualties. Casualty accidents and their causes occurring in the operation of lifting machinery mainly include the following:

2.1 squeezing collider

squeezing collider refers to the operator being squeezed and collided by the running lifting machinery

the squeezing and collision of lifting machinery with people is also a common casualty accident in lifting machinery operation, which is also very dangerous and has serious consequences, often leading to death

there are four main situations of squeezing and bumping people in overweight mechanical operation

(1) lifting objects (tools) swing, squeeze and collide with people during the operation of lifting machinery. The reasons for this situation are as follows: first, due to the improper operation of the driver, the speed of the mechanism changes too fast during operation, resulting in large inertia of the hoisted objects (tools); Second, due to the wrong command and unreasonable lifting route, the lifted objects (tools) squeeze and collide with people in the violent swing

(2) the lifting objects (tools) are placed unsteadily and fall and hit people. The reasons for this situation: first, because the compressive strength is the maximum pressure load encountered when an iron ore pellet is completely broken, the lifting objects (tools) rotate improperly, and the necessary safety protection measures are not taken for the unstable rotation of major lifting objects (tools); Second, due to the poor management of the lifting operation site, the lifting objects (tools) suddenly fell and hit people

(3) being squeezed and collided in the operation of commanding or repairing mobile cranes, that is, being squeezed and collided by the crane machinery in operation (rotation) as the commander between the operating mechanism of lifting machinery and the slewing mechanism. The reasons for this situation are: first, the commander's position is improper (such as standing between the slewing boom and the body); Second, the driver squeezed and touched people when starting the lifting machinery (slewing) rashly because the necessary safety protection measures were not taken during the maintenance operation

(4) being squeezed and collided during patrol inspection or maintenance of bridge crane, that is, the operator is squeezed and collided by the running crane between the crane and the building (structure) (such as standing on the crane running track of bridge crane or standing on the patrol pedestrian passage). The reasons for this situation: most of the bridge crane maintenance operations, one is due to the lack of mutual contact between inspectors or maintenance operators and drivers; Second, because the necessary safety protection measures (such as the device to fix the crane in the crane operation section) were not taken during the maintenance operation, the driver suddenly started the crane to squeeze and collide people

2.2 electric shock (electric shock)

electric shock (electric shock) refers to the electric shock (electric shock) caused by the operator touching the live body during the operation of lifting machinery

most crane operations are in the working environment with electricity, and electric shock (electric shock) is also a common casualty accident in crane operations

there are four main situations of electric shock (electric shock) of operators in lifting machinery operation

(1) the driver touches the sliding contact line

when the crane cab is set on the same side of the sliding contact line, the driver touches the sliding contact line and gets an electric shock when getting on and off the crane

the reasons for this situation are as follows: first, the cab should not be set on the same side as the sliding contact line because of the unreasonable setting; Second, the driver got an electric shock (electric shock) because the crane was not equipped with a protective plate () near the end of the sliding contact line

(2) the lifting machinery touches the high-voltage transmission line when working in the open air, that is, the mobile crane working in the open air touches the high-voltage transmission line under the high-voltage transmission line or the tower crane is beside the high-voltage transmission line, and touches the high-voltage transmission line in the process of boom extension, bending and rotation, which makes the lifting machinery live, causing the operator to get an electric shock (electric shock). The reasons for this situation: first, the hoisting machinery did not take necessary safety protection measures (such as installing screen protection and isolation) when operating under the high-voltage wire (side); Second, due to improper command and wrong operation, the lifting appliances were electrocuted and electrified, resulting in electric shock (electric shock) to operators

(3) electric leakage of electrical facilities. The reasons for this situation: first, the electric leakage occurred due to the untimely maintenance of the electrical facilities of lifting machinery; Second, the driver was electrocuted (shocked) due to electric leakage of facilities due to the absence of safety insulation pads in the cab

(4) the lifting steel wire rope touches the sliding contact line, that is, the lifting steel wire rope touches the sliding contact line due to the oblique lifting or the violent swing of the lifting object (tool) during the lifting process, causing the operator to get an electric shock. Reasons for this; First, due to improper lifting methods, the inclined lifting violates the safety regulations; Second, because the lifting machinery is not equipped with a sliding contact line protective plate near the end of the contact line, the lifting wire rope touches the sliding contact line and becomes energized, resulting in electric shock (electric shock) to the operators

2.3 falling from height

falling from height refers to the falling of lifting machinery operators from lifting machinery

falling from height mainly occurs in the installation and maintenance of lifting machinery

there are three main situations in which operators fall from height during lifting machinery operation

(1) the maintenance cage falls. Reasons for this: first, the design structure of the maintenance cage is unreasonable (such as the height of the protective rod is not enough, the material selection does not meet the specified requirements, and the design strength is not enough); Second, due to improper operation of maintenance personnel; Third, because the maintenance operators did not take necessary safety protection measures (such as wearing safety belts), each glass fiber was evenly coated with plastic materials, causing the maintenance cage operators to fall

(2) fall when crossing the crane. The reasons for this situation are: first, the maintenance personnel did not take necessary safety measures (such as wearing safety belts, hanging safety ropes, erecting safety frames, etc.); Second, the operators were careless and operated against rules, resulting in falling from height

(3) during the installation or disassembly of the lifting tower (section) tower crane, the tower (section) and the operator fall. The reasons for this situation: first, the design structure of the tower body (section) is unreasonable (there are hidden dangers in the disassembly and assembly of the fixed structure); Second, due to improper disassembly and assembly methods, the operators cooperated with the commander incorrectly, causing the tower body (section) to fall together with the operators