Pumping tubes

Equipment Failure pumps, tubes in heat exchangers and furnaces, turbine drivers and governor, compressor cylinder valves are examples of equipment which might fail and cause overpressure in the process. If an exchanger tube splits or develops a leak, high pressure fluid will enter the low side, overpressuring either the shell or the channels and associated system as the case may be. 

Recommended for high-pressure (>600 psi), high-temperature applications. Tube shape allows extreme temperature differences (AT>250°F) across the bundle. Often used as integral column bottom reboiler and as tank suction heater to preheat product before pumping. Tube side cannot be made single-pass. 

Auxiliary equipment, such as two pumps, tubing valves and electrolyte reservoirs is also necessary. 

The total investment cost for the aquifer system (wells, submersible pumps, tubing, control equipment, electrical cables, well chambers and heat ex- changers) was approx. 350,000 Euro. The specific investment cost is then roughly 370 Euro/kW. 

Four Varian 550 turbo pumps are used in parallel. They are backed up by an Edwards mechanical booster (2500 m3/h) and a Pfeiffer uni-dry (60m3/h). A maximum circulation rate could be achieved at about 7 mmole/s. The 3Fie pumping tube is inserted from the top of the cryostat. 

Aschematic diagram of the flow injection system used by Anderson [126] is shown in Fig. 2.4. An Ismatec model MP13 peristaltic pump was used. Different flow rates were obtained by changing the pump tube diameter, as indicated in the legend to Fig. 2.4. The injection port was a rotary valve [131,170]. The sample volume could be varied between 10 and 1000 pi simply by changing the length of the sample loop. 

Figure 6.1. Manifold for the automatic determination of ammonia ( on pump tube R1 indicates Solvaflex tubing). Source [2]...

In a practical FIA system, peristaltic pumps are usually used since they have several channels, and different flow rates may be achieved by selection of a pump tube with a suitable inner diameter. 

Fig. 13.6 Modified automated total mercury manifold. Numbers in parentheses correspond to the flow rate ofthe pump tubes in ml min-1. Numbers adjacent to glass coils and fittings are Technicon Corp. part numbers.

The volume dispensed, purged, recycled, or discarded should be routinely checked. Pumping tubes can wear out... 

The mixing of the sample and reagents in predetermined proportions rather than specific volumes is a fundamental principle of continuous flow analysis and is achieved by using a constant-speed roller bar peristaltic pump and flexible plastic delivery tubes of different internal diameters. These pump tubes are stretched between two plastic end-blocks, which hold them taut between a... 

Figure 6.8 Flow diagram for the measurement of glucose using alkaline ferri-cyanide. The pump tubes are specified with respect to their internal diameters and position on the end-blocks. The colour coding of the tubes is ...

In general, chromatography columns should not be left connected to pumps or to the UV monitors in salt solutions. Always include a wash step with water to remove any salt from the system. It is preferable to store the columns disconnected in 20% ethanol and to rinse the entire FPLC system, including pumps, tubing, and UV flow cell with water, followed by 20% ethanol. Keep a record of the column performance, and use it to determine when filter changes or columncleaning steps are required. 

The TRAACS 800+ shown in Fig. 2.18 consists of one or more analytical consoles, a random-access sampler and personal computer (PC). The analytical console is fitted with two peristaltic pumps which can each handle up to 10 pump tubes. The analytical manifolds are located above the pumps and utihze glass parts 1 mm in diameter, in order to keep reagent consumption low. Heating baths, UV digesters and dialysers can be built into the manifold. 

It operates by the principle of differential pumping, using a series of peristaltic pumps, each of which operates under similar conditions. The pump tubing used on each pump is the same, and the variable-speed pump with which the initial dilution is provided wiU normally pump at full speed with the same flow rate as the other two pumps. The variable speed pump is set to operate at, for example, 80% of the fixed speed pumps. Diluent is... 

The analysis speed is determined (a) by the ICP or AA system flush-out characteristics and (b) by the mixing and sample-transfer rates of the dilutor. TTie latter can readily be adjusted by increasing the flow-rate of the peristaltic pump tubes. The steady diluted stream can easily be adjusted in order that only a few seconds is required to flush out the previous sample and to set up a steady stable flow. Although peristaltic pumps are... 

Figures 7.9(a) and 7.9(b) show two different approaches to the samphng of the dissolution baths prior to analysis. Figure 7.9(a) shows the most commonly installed system, which uses a series of spectroscopic cells, one to coincide with the hath being sampled. The system uses a peristaltic pump to withdraw the sample through the pump tubing and into...

The outflow end of the pump tubing is connected directly to the components of the chemistry module. This module consists mainly of connectors and glass mixing coils. Proprietary modules are available, of course, but it is perfectly feasible to assemble the necessary components on a plastic tray fitted with four legs. Pump tubing and connectors are available from many suppliers. Apart from the OEMs, sources include ... 

Pump tubing is supplied by the above sources, also Elkay Laboratory Products UK Ltd ... 

A pump tube has been included for the wash waste for reservoirs that do not have a gravity overflow. 

The pump tubes in some published manifold diagrams are labelled with the internal diameters of the tubes. We will use the more common convention of labelling with flow rates in ml min k... 

Pump tubes are designated by a colour code, which may also be used in the literature. Some common colour codes are listed in Table 5.1. 

Pump tubes are available in different materials depending on the liquid to be pumped, e.g. for solvents or concentrated acids. Flow rates for these other materials will be different than for standard PVC. Pump tubes may also be available in a specially calibrated or measured flow rate quality at extra cost. Unless specified for medical purposes or to meet regulations, the standard quality is normally adequate. See Chapter 1, Peristaltic pumps. ... 

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