Piping and instrumentation diagram

With this procedure it is possible to start the pump procurement activities significantly before the completion of the planning-intensive and detailed pipe routing. 

All technical and commercial aspects of the quotations have to be examined. 

In addition to the design point other operating points should be inserted in the characteristic curve to emphasize the consequences of different load stages. 

The distance between the existing NPSHA-value and the required NFSHp-value of the pump has to be verified, too. With distances of less than half a metre there is a risk of cavitation, since the measuring of the NPSHR-values occurs with the already beginning cavitation (a pump head drop of 3%). In case of cavitation-prone pumps as e.g. condensate pumps it should also be taken into account that the NPSHR-value of the pump can change considerably depending on the volume flow. 

In critical cases, a NPSHR-value progression curve over the interesting operating range should be demanded from the manufacturer. 

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P IDs (piping and instrumentation diagrams) should identify instruments, sample locations, the presence of sample valves, nozzle blinding, and control points. Of particular importance are the bypasses and alternate feed locations. The isolation valves in these hues may leak and can distort the interpretation of the measurements. 

Piping and Instrument Diagram (P ID) A diagram that shows the details about the piping, vessels, and instrumentation. 

Fig ure 11-23. Piping and instrumentation diagram of a fermenter. (Source Bartow [13], Supersizing the aerobic fermenter," Chem ca Engineering, pp. 70-75, July 1999. Courtesy of Chemical Engineering.)... 

FIAZOP is a formally struetured method of systematieally investigating eaeh element of a system for all ways where important parameters ean deviate from the intended design eonditions to ereate hazards and operability problems. The HAZOP problems are typieally determined by a study of the piping and instrument diagrams (or plant model) by a team of personnel who eritieally analyze eflfeets of potential problems arising in eaeh pipeline and eaeh vessel of the operation. 

Piping and Instrument diagrams (P IDs - not shown) may be even more appropriate for showing these details and to provide information for PSA. The P IDs are used to describe the relationships between equipment and instrumentation and other relevant information that enhances clarity. 

This phase is where the basic design work, such as process flow design, is performed. Piping and instrumentation diagrams (P IDs) and equipment... 

Discuss the main differences between a process flow diagram (PFD) and a process piping and instrument diagram (P ID). 

Drawings should conform to accepted drawing conventions, preferably those laid down by the national standards. The symbols used for flow-sheets and piping and instrument diagrams are discussed in Chapter 4. Drawings and sketches are normally made on detail paper (semi-transparent) in pencil, so modifications can be easily made, and prints taken. 

Devise a control system for this reactor, and draw up a preliminary piping and instrument diagram. The follow points need to be considered ... 

In the detailed design stage, everything must be specified. Each phase of the preliminary design must now be done in much more detail. The flow sheets develop into piping and instrument diagrams. The duty requirements for a piece of equipment become a specification sheet. The layout drawings may be replaced by a scale model, and a construction bid or detailed cost estimate is obtained to verify the previous cost estimate. 

HAZOP studies may be made on batch as well as continuous processes. For a continuous process, the working document is usually a set of flow sheets or piping and instrument diagrams (P IDs). Batch processes have another dimension time. Time is usually not significant with a continuous process that is operating smoothly, although start-up and shutdown must also be considered, when the continuous process will resemble a batch process. For batch processes, the working documents consist not only of the flow sheets or P IDs but also... 

Process hazard analyses are conducted in accordance with formal procedure, with piping and instrumentation diagrams for reference. 

Piping and Instrumentation Diagram Probability of Failure on Demand Process Hazard Analysis Pressure Indicator Protection Layer Preventive Maintenance Process Safety Incident Database Process Safety Management Pressure Safety Valve (Relief Valve)... 

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