Inlet pressure, monitoring

An expander emergeney trip valve, eapable of elosing in less than one-half seeond, must be installed elose to the expander inlet flange. A 60-80 mesh sereen, differential pressure monitor, and shutdown must be installed between the trip valve and the expander inlet. Additionally, it is highly reeommended that a 40-60 mesh sereen be installed upstream of the eompressor inlet for use during the initial startup period. 

Inlet pressures 2—7 bar, larger flow rates. Duplicate streams with two-stage governing as in (3) above or duplicate streams each having monitor and active governors and a slam-shut valve ... 

Our client had been monitoring the inlet pressure to the compressor, at the Px pressure point. But we found that the actual compressor inlet pressure was 2 psi lower, due to the in-line basket filter. This filter had apparently never been cleaned. Our client then asked us to calculate the percent of the motor amps being wasted across the partially plugged basket filter. 

Since Mak s Isothermal flow chart is intended for relief manifold design, it supports calculations starting with P2, the outlet pressure, that is atmospheric at the flare tip, and back-calculates each lateral s inlet pressure. Pi. These inlet pressures are the individual relief valves back pressures. The chart parameter is M2, the Mach number at the pipe outlet. Having M2 is very useful in monitoring proximity to sonic velocity, a common problem in compressible flow. 

The inlet pressure for the filter holder is measured on the upstream side of the membrane as the fluid enters. The outlet pressure is also monitored on the upstream side of the membrane as the retentate exits the filter holder device. The difference between the inlet and outlet pressure is proportional to the circulation rate while the sum of the inlet and outlet pressures is proportional to the average trans membrane pressure. 

After passage through a rotometer, molecular gas entered the reaction system through a capillary orifice, A. Pressure was monitored by a McCloud gauge attached to side arm E, located 50 cm. beyond the gas inlet. Pressure was maintained at 1.2 torr and flow rates at 150 cc. per minute, S.T.P. U.S.P. grade oxygen and instrument grade carbon dioxide were used. 

It should be noted that an alternative procedure of connecting the pressure monitor to the gas inlet line, upstream from the collision chamber, necessarily introduces error, simply because the pressure is a rapidly changing function along the inlet line. Such a procedure is unacceptable even though theoretical corrections can be made, the reliability of these corrections is not established. 

The Pressure Monitor System (sometimes called the "Panelllt") monitors coolant flov contlntilty In each Individual process tube (200 at the old reactors and 3220 at the K Reactors) A venturi or orifice Is located at the Inlet nozzle of each tube ... 

After 5 min, the RO high-pressure pump, P-161, starts provided the inlet pressure exceeds the minimum permissible value as monitored by PSL-161. 

The pillow test per GRI-GT15 uses the candidate fabric prefabricated into the shape of a pillow from which a flanged connector and a calibrated vertical standpipe are attached. The fabric enclosure is small and the amount of slurry needed per test is much less than with the hanging bag test. More important, the hydraulic head (converted to inlet pressure) can be monitored over time, resulting in a quantitative assessment of the system including the specific effects of the fabric, slurry, and its additives. A pillow test in progress is shown in Fig. 21.3. 

The safety principle of the Super LWR and Super FR is compared with those of PWRs and BWRs in Table 1.7. The main coolant flow rate and turbine inlet pressure are monitored and used for the emergency signal, instead of the water level ofLWRs. 

A more sophisticated and increasingly popular method of on-condItion maintenance is to monitor the performance of equipment on-line. For example, a piece of rotating equipment such as a turbine may be monitored for vibration and mechanical performance (speed, inlet and outlet pressure, throughput). If a base-line performance is established, then deviations from this may indicate that the turbine has a mechanical problem which will reduce its performance or lead to failure. This would be used to alert the operators that some form of repair is required. 

Monitoring should include the usual parameters worthy of surveillance in high-speed turbo machinery the temperature of journal bearings, vibration and axial position of the pinions, inlet and discharge temperatures combined with discharge pressure from the individual compressor stages, and various lube oil system devices. Competent manufacturers make sure all measurement locations are completely prewired on the machine and made available at predefined interfaces or in terminal boxes for connection at the plant site. 

Compressor analysis is done by monitoring the inlet and exit pressures and temperatures, the ambient pressure, vibration at eaeh bearing and the pressure and temperature of the lubrieation system. Table 19-5 shows the effeet various parameters have on some of the major problems eneountered in a eompressor. Monitoring these parameters allows the deteetion of ... 

The turbine eompressor effieieney and pressure ratio are elosely monitored to ensure that the turbine eompressor is not fouling. Based on these eomputations the turbine eompressor is water washed with mineralized water, and if neeessary adjustment of Inlet Guide Vanes (IGV) is earried out to optimize the performanee of the eompressor, whieh amounts to between 60-65% of the total work produeed by the gas turbine. 

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