Mechanical integrity instruments

Equipment used to process, store, or handle highly hazardous chemicals must be designed constructed, installed and maintained to minimize the risk of release. A systematic, scheduled, test and maintenance program is preferred over "breakdown" maintenance " that could compromise safety. Elements of a mechanical integrity program include 1) identification and categorization of equipment and instrumentation, 2) documentation of manufacturer data on mean time to failure, 3 ) test and inspection frequencies, 4) maintenance procedures, 5) training of maintenance personnel, 6) test criteria, and 7) documentation of test and inspection results. 

This phase involves the performance of check-out and nm-in activities to ensure that equipment and piping are mechanically integrated, functionally located and free of obstructions It is also necessary to ensure that instruments and controls are fimchoning properly and that all previously identified problems have been addressed. All maintenance and operating procedures need to be verified as correct. 

Covers mechanical integrity programs for safety critical instruments and safety relief... 

The Role of Mechanical Integrity in Chemical Process Safety 239 Testing Safety Critical Process Instruments at a DuPont Plant... 

Are tests for safety critical process instrumentation completed on time Are mechanical integrity inspections completed on time ... 

When the susceptibility of a component goes up, the failure rate increases rapidly. Manufacturers of instrumentation for safety instrumented applications will typically publish the useful life numbers for their products. A mechanical integrity program needs to address all instruments in safety applications before the end of their useful Hfe. 

Equipment criteria call for verification of mechanical integrity of equipment and proper functioning of instrumentation prior to the experiment, a neutron source, two independent neutroiiHCoimting devices, sind a sigtial indicating neutron level, either audible or otherwise apparent It is proposed that for example, a flashing light be added to the last item. 

Many points important in reactor design have not been discussed. Nothing has been said about selection of materials of construction, mechanical construction, instrumentation and process control, integration of heat recovery into the overall plant energy system, etc. But it is hoped that the paper will anyhow give an idea about the complexity of the problems encountered in the reactor design and about the solutions which are applied in order to obtain satisfactory results in industrial practice. 

Mechanical flow diagram (MFD). See P ID fpiping and instrumentation diagramV Mechanical integrity, 857 Membrane separation, 71-72 MENS (mass-exchanger networks)... 

After the mechanical integrity of each system has been proved, it is flushed through very thoroughly and drained out. The instrument air supply manifold is normally pneumatically tested. It is essential to blow the air supply pipework through very thoroughly after pressure testing to remove all pipe debris. 

Elements of a mechanical integrity program include identifying and categorizing equipment and instrumentation, inspections and tests and their frequency maintenance procedures traiifing of maintenance personnel criteria for acceptable test results documentation of test and inspection results and documentation of manufacturer recommendations for equipment and instrumentation. 

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