The most important thing is to pay attention to th

  • Detail

Pay attention to the safety of equipment in the whole life cycle

make the safety of equipment perfect from the aspects of technology, machinery, organization, etc. in the whole life cycle

in February this year, a serious accident occurred in the thermal power plant in Middletown, USA, which caused many deaths. At that time, the equipment involved in the accident was still under construction, and it was planned to start production by the middle of the year. This brings a problem: how will the safety protection function of the equipment play a role in safety assurance before the equipment is officially put into operation

what are the possible reasons for such failures? I am not making a belated decision, but I am sure that the overall safety protection performance of the equipment should be considered from all aspects of mechanical, electrical and automatic safety control; At the same time, we should also pay attention to the safety protection of the equipment in the whole service life cycle from the perspective of production, construction and organization. As long as the external force is adjusted on the tensile force change experimental machine, we can get different loading path performance. IEC61508 standard is the basic standard related to functional safety protection. Even if the application scope of equipment is limited to the scope of electrical, electronic and programmable control systems, the basic idea of mechanical safety protection can also be applied. This standard divides the possible faults into two categories: accidental faults and systematic faults

accidental failure, such as sudden failure of electrical components, can specify a failure probability for accidental failure. There are many measures to reduce accidental faults, such as using large-scale components, redundancy, or fault diagnosis and analysis system

typical systematic faults refer to software errors or errors in design. These errors can clearly find out the causes of the errors. To eliminate these errors, we can only take measures in the work organization method, such as the functional safety management FSM system

the accident and fault data in the past few years show that the most common errors are accidental errors. Through the efforts of the research team, we have successfully realized the SIL method to calculate and verify the working reliability of the equipment (see ne93 "fault data collection" and ne130 "equipment safety protection instrument"). We have also made great efforts in the early identification and description of accidents and errors by using the new fault diagnosis system, and achieved good results (see ne129 "planned identification resource management"). But what countermeasures should be taken for systematic errors? Annex 2 of VDI/vde2180 standard has made corresponding provisions on the safety protection measures to be taken in the whole service life cycle of equipment in the field of automation technology, which is expected to reach 85000t in the 1990s

systematic errors do not only occur in the field of automation technology, but almost all errors in mechanical systems are systematic errors. Especially when the mechanical system is abnormal occasionally, it can also be explained with systematic errors afterwards, and similar faults can be avoided in the future. These systematic errors do not happen by accident, so they can also be managed by the safety protection management system

in addition, human factors cannot be ignored. People who are not sil3 (third level safety certification) will also have accidental errors, such as accidental lack of concentration, temporary amnesia of what they have done, etc. in this case, it is very effective for two people to operate at the same time. Lack of technical training will also lead to systematic errors, resulting in "congenital deficiencies". The wrong information will also cause the operator to not get the correct information in time, resulting in the production of waste products. Human systematic errors can only be eliminated through the methods of production organization, such as functional safety management FSM

however, the safety of the equipment is not only the safety after production, but also the safety protection of the equipment should be treated carefully during the technical transformation and shutdown of the equipment. When an assembly company does not know that the disabled equipment has just been started and removed, and there is no strong magnetic field interfering with a flange, when the technicians do not know that the process equipment produces new products and still adjust the process production equipment according to the limit data of the production of old products, and when the repairmen do not know that this pipeline is full of high-pressure media, it will not only be the problem of equipment safety, There may even be major accidents that may lead to casualties. Therefore, the safety management system can not be ignored for the safety of equipment, and the following aspects need to be considered

for general material experiments, it is completely sufficient to choose a level 1 experimental machine.

there is no objective conflict between product quality, availability of process equipment and safety. Despite the great pressure of production, production and technical leaders should also take time to solve safety technical problems

although there is a contract, there should be no shortage of professionals

give the production operators enough time to participate in the required professional training and continuous training

the information should be reliably conveyed to every relevant person

the role of equipment instructions and documentation cannot be ignored

the safety of equipment is not that a series of acceptance inspections are completed during equipment acceptance, and everything will be fine if it is handed over to equipment operators and maintenance workers. The safety guarantee of equipment needs to be constantly upgraded and requirements are constantly put forward. Within the whole service life cycle of equipment, the safety of equipment should be improved from the aspects of technology, machinery, organization, etc

Copyright © 2011 JIN SHI