Equipment performance tests, example

Maintenance/ reliability engineering The QRA team will need information about process configurations during maintenance activities and historic data on equipment performance. For example, how often are the instruments calibrated, does the same person calibrate redundant instruments, and how often do the pumps require repair QRA results are always more accurate if based on actual plant data, and maintenance/testing policies can make an order of magnitude difference in the calculations. Expect to commit about 1 staff-week per month over the life of the project. 

It is good to calibrate the equipment frequently, for example, every week. If the test sample contains high volatile content, it is preferable that calibration be performed after each experiment. Make all measurements within the range of calibration points, and do not extrapolate the calibration line. Make all measurements in the same direction of change (i.e.,from lower to higher water activity or higher to lower water activity). 

The PV of a new facility [21] must be documented in such a way to ensure that the facility s design and the operations within it are fully covered. An outline of such activities is listed in Table 4. For example, the validation of a new facility makes it necessary to document the equipment performance under relevant conditions. All process (or facility) equipment will undergo IQ testing to make sure that each piece of equipment operates as it was designed to do. The technologist will determine how the equipment s performance will vary without the influence of the process material (OQ). This information will form the basis for the remainder of the validation report. From a QA viewpoint, it should also be noted that this information might be useful if it is compared against the parameter measurements under load conditions. Since this information is more properly included in the performance qualification (as process optimization), however, it should not become a part of the validation protocol... 

Some types of equipment require production tests , type tests , performance tests , routine tests , abbreviated tests or special tests , or a combination of these tests. The subtitles are sometimes used with different meanings. Production tests are required for complex equipment such as high-voltage generators and motors, and these tests are performed in the factory before the complete unit is assembled. For example the rotors are balanced without the stator, air-to-water heat exchanges can be tested to withstand hydraulic pressure, winding insulation and individual coil insulation can be tested. 

Performance tests are those tests that need to be carried out on combined equipment such as a gas-turbine driven generator or a pump driven by a high-voltage motor. In such cases the dynamic relationship between the various equipments is of interest. For example, rotor vibration, critical speeds, run-up time to full speed, starting up and shutting down sequences, full-load and over-load performances, heat dissipation and cooling medium performance. 

The pilot plant was also used to perform tests with samples produced in-situ using equipment from different suppliers. This was used, for example, to determine the best type of filter and to obtain adequate design parameters. This information was used in the feasibility study. The results obtained during piloting can be summarized as follows ... 

The number and severity of fabrication and installation deficiencies are also directly related to quality control efforts during construction phases of a project. For example, a review of contractor submittals, or shop drawings, usually helps assure comphance with contract documents before equipment is delivered to the job site. Site inspections during installation work may detect deficiencies in design or workmanship before they lead to operational problems and performance difficulties. In addition, specific operating and performance testing as a prerequisite to final accepfance is a key element in assuring that a system is installed properly. 

Testing Inspection may not be enough to determine performance of some personal protective equipment. Some equipment requires testing. For example, there are devices available to test respirator fit. Lifelines need periodic testing to make sure they can carry required loads. 

Test exchangers require both operating attention and maintenance work, making their use relatively expensive and troublesome. The method has the distinct advantage that it correlates reliably with equipment performance. While used less extensively thi2m the methods described previously, a number of examples of use have been documented 10-13 ... 

Table 1 is condensed from Handbook 44. It Hsts the number of divisions allowed for each class, eg, a Class III scale must have between 100 and 1,200 divisions. Also, for each class it Hsts the acceptance tolerances appHcable to test load ranges expressed in divisions (d) for example, for test loads from 0 to 5,000 d, a Class II scale has an acceptance tolerance of 0.5 d. The least ambiguous way to specify the accuracy for an industrial or retail scale is to specify an accuracy class and the number of divisions, eg. Class III, 5,000 divisions. It must be noted that this is not the same as 1 part in 5,000, which is another method commonly used to specify accuracy eg, a Class III 5,000 d scale is allowed a tolerance which varies from 0.5 d at zero to 2.5 d at 5,000 divisions. CaHbration curves are typically plotted as in Figure 12, which shows a typical 5,000-division Class III scale. The error tunnel (stepped lines, top and bottom) is defined by the acceptance tolerances Hsted in Table 1. The three caHbration curves belong to the same scale tested at three different temperatures. Performance must remain within the error tunnel under the combined effect of nonlinearity, hysteresis, and temperature effect on span. Other specifications, including those for temperature effect on zero, nonrepeatabiHty, shift error, and creep may be found in Handbook 44 (5). The acceptance tolerances in Table 1 apply to new or reconditioned equipment tested within 30 days of being put into service. After that, maintenance tolerances apply they ate twice the values Hsted in Table 1.

Leaf Tests A bomb filter is used for small-scale leaf tests to simulate the performance of pressure-leaf (leaf-in-shell) filters. The equipment used is a small [50.8- by 50.8-mm (2- by 2-in)] leaf, covered with appropriate filter medium, suspended in a cell large enough to contain sufficient shiny to form the desired cake (Fig. 18-108). The shiny may be agitated gently, for example, by an air sparger. 

For sampling a relatively small number of sources, a simplified calculation form may be used. Such forms enable the office personnel to perform the arithmetic necessary to arrive at the answers, freeing the technical staff for proposals, tests, and reports. Many of the manufacturers of source-testing equipment include example calculation forms as part of their operating manuals. Some standard sampling methods include calculation forms as a part of the method (8). Many control agencies have developed standard forms for their own use and will supply copies on request. 

The costs of an intervention have to be compared with the results of this intervention (Drummond et al. 2004). These results can be outputs, outcomes, and impacts (Fig. 2). An output is the direct result of a production process. Agents of production (resources) are transformed to generate a certain commodity or service (output). For instance, equipment, reagents, and the knowledge of a laboratory technician are used to perform a certain resistance test. Other examples of outputs are contacts, admissions, or prescriptions. 

In most bench-scale reaction instruments, it is also possible to perform adiabatic experiments, although precautions have to be taken to avoid an uncontrollable runaway in the final stages. From these types of experiments, the temperature constraints at which, for example, side reactions or decomposition reactions start, together with the possible control requirements, can be obtained. If the adiabatic temperature rise may exceed, say, 50 to 100°C, it is safer to use other methods to obtain similar information, such as the DSC, ARC, or Sikarex, because these instruments use relatively small amounts, thereby decreasing the potential hazard of an uncontrollable runaway event in the test equipment. 

Key Performance Indicators Preparation for maintenance, the control of modifications, and the testing of protective equipment are examples of key performance indicators i.e., taken together, they indicate uie quality of the plant s and company s process safety. If they are below standard, the plant is at risk. The usual measure of safety, the lost-time accident (LTA) rate, does not measure process safety. Many companies that had a low LTA rate and assumed that their process safety was therefore under control have experienced serious fires and explosions. 

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