Electrical safety production technology of the hot

Mechanical and electrical safety production technology

(4) Petrochemical General machinery: petroleum drilling and production machinery, oil refining machinery, chemical machinery, gas compressors, refrigeration and air conditioning machinery, paper machinery, printing machinery, plastic processing machinery, pharmaceutical machinery, etc

(5) electrical machinery: generators, transformers, motors, high and low voltage switches, wires and cables, batteries, welding machines, household appliances, etc.

(6) machine tools: metal cutting machine tools, forging machinery, casting machinery, woodworking machinery, etc

(7) cars: trucks, road buses, cars, modified cars, motorcycles, etc

(8) instruments and meters: automation instruments, electrical instruments and meters, optical instruments, composition analyzers, automotive instruments and meters, electrical materials machinery, electrical education equipment, cameras, etc

(9) basic machinery combines the flexibility of rubber with the strength and availability of thermoplastic; Zytel has high heat resistance, chemical resistance and hydrolysis resistance; Surlyn provides many functions: bearings, hydraulic parts, seals, powder metallurgy products, standard fasteners, industrial chains, gears, molds, etc

(10) packaging machinery: packaging machinery, metal packaging items, metal containers, etc

(11) environmental protection machinery: water pollution prevention and control equipment, air pollution prevention and control equipment, solid waste treatment equipment, etc. are worth mentioning

(12) other machinery

2) main mechanical products systematically produced in non mechanical industry

(1) railway machinery

(2) construction machinery

(3) textile machinery

(4) light industrial machinery

(5) ships, etc

    2. Classification of main products of machinery

the main machinery used in the production of machinery enterprises is divided into six categories:

(1) metal cutting machine tools

(2) forging machinery (forging, punching and shearing machinery)

(3) hoisting machinery

(4) woodworking and casting machinery (woodworking machinery, casting machinery)

(5) special production machinery

(6) other machinery

(II) intrinsic safety of mechanical design and safety devices

1 Mechanical design intrinsic safety

1) intrinsic safety

intrinsic safety refers to a mechanical safety method in which the designer of machinery takes measures to eliminate mechanical hazards in the design stage. It includes: eliminating dangerous parts in the design, reducing or avoiding the need to deal with work in dangerous areas, providing automatic feedback equipment and keeping moving parts in a medium sealed state

2) failure safety

the designer should ensure that there is no danger when the machine breaks down

this type of device includes the operation limit switch, the preset braking device to limit the impact and movement that should not occur, the device to set the handle and prevent falling, the fail safe power limit switch, etc

3) positioning safety

place the parts of the machine in an inaccessible place and achieve safety through positioning. However, the designer must consider the dangerous parts that will not be touched under normal circumstances, but may be touched under some circumstances, such as climbing a ladder to repair the machine

4) machine layout

a reasonable machine safety layout in the workshop can significantly reduce accidents. The following factors should be considered in the safety layout:

(1) space: easy to operate, manage, maintain, debug and clean

(2) lighting: including general lighting in the workplace (natural light and artificial lighting, but to prevent dazzling) and special lighting for operating the machine

(3) pipe and line layout: do not hinder the safe access near the machine, avoid bumping, and have enough upper space

(4) access safety during maintenance

    2. Safety device design of machine

safety devices of machine can be classified as follows according to control mode or action principle

1) introduction of common types of fixed safety devices

such as

when possible, fixed safety devices that prevent contact with dangerous parts of the machine should be designed and set. The device shall automatically meet the environmental and process conditions of machine operation. The effectiveness of the device depends on its fixing method, the size of the opening, and the distance from the dangerous point after it is opened. The safety device shall be designed as a device that can be removed only with special tools such as screwdriver, wrench, etc

2) chain safety device

basic principle of chain safety device: the machine can operate only when the safety device is closed; The safety device can be opened only when the dangerous parts of the machine stop moving. The interlocking safety device can take the form of mechanical, electrical, hydraulic, pneumatic or combined. When designing the interlock device, it must be ensured that in case of any failure, personnel will not be exposed to danger

3) control safety device

it is required that the machine can stop moving quickly, and the control device can be used. Principle of control device: the machine can start only when the control device is completely closed; When the operator turns on the control device, the operation program of the machine starts to work; If the control device is disconnected, the movement of the machine will quickly stop or reverse. Usually, in a control system, the control device will not be locked in the closed state when the machine is running

4) automatic safety device

the mechanism of automatic safety device is to remove the human body exposed to danger from the dangerous area. It can only be used in an environment where there is enough time to complete such actions without causing injury. Therefore, it is limited to low-speed machines

5) isolation safety device

isolation safety device is a device that prevents any part of the body from approaching the dangerous area, such as a fixed fence

6) adjustable safety device

in the case that it is impossible to isolate the dangerous area, some adjustable fixed safety devices can be used. The possible protective effect of these safety devices depends to a large extent on the use of operators and the correct adjustment and reasonable maintenance of the devices issued by the Ministry of safety, industry and information technology in the management requirements for automotive hazardous materials and recyclability (Exposure Draft)

7) automatic adjustment safety device

the automatic adjustment device automatically opens due to the movement of the workpiece, and returns to the closed state after the operation

8) tripping safety device

the function of tripping safety device is to automatically stop or reverse the movement of the machine before operating to a dangerous point. Such devices rely on sensitive tripping mechanisms, and also on the ability of the machine to stop quickly (this can be achieved by using brakes)

9) two handed control safety device

this device forces the operator to operate the controller with two hands. However, it can only provide protection for the operator, not for others who may be close to the dangerous area. Therefore, it is necessary to set up safety devices that can provide protection for all people. When using this kind of device, there should be a proper distance between the two controls, and the machine should not run until both control switches are turned on, and the control system needs to be restarted after each stop of the machine

(III) dangerous points of mechanical production power station building and general safety technology management requirements

facilities that provide power for mechanical production process, also known as power station building. Mainly: Boiler and auxiliary equipment; Gas station; Oxygen generation station; Air compressor station; Acetylene station; The boundaries of different colors are not clear, transformation and distribution stations, etc

    1. Boiler and auxiliary equipment safety technology

this content is applicable to fixed boilers that bear pressure and generate steam with water as the medium

1) overview of dangerous points

boiler is a widely used energy conversion equipment in the production and daily life of industrial enterprises. Because some of its components are not only baked by high-temperature flue gas and flame, but also bear great pressure, and the working environment is relatively bad, it is a special equipment with explosion risk