Pumps/pumping priming systems

If the suction level is above the pump there is usually no problem in priming (that is, ensuring that the pump suction system is full of liquid) unless it is pumping a volatile and vapor locks when stationary. In many... 

Disconnect tubing at guard column (if present) or analytical column inlet. Check for flow. Purge pump at high flow rate (10 ml/ min), prime system if necessary. (Prime each pump head separately.) If system has check valve, loosen valve to allow air to escape. If problem persists, flush system with 100% methanol. If problem still persists, contact system manufacturer. 

Control Room. The control room location can be critical to the efficient operation of a faciHty. One prime concern is to locate it the maximum distance from the most ha2ardous units. These units are usually the units where LPG or other flammables, eg, hydrocarbons that are heavier than air, can be released and accumulate at grade level. Deadly explosions can occur if a pump seal on a light-ends system fails and the heavier-than-air hydrocarbons coUect and are ignited by a flammable source. Also, the sulfur recovery unit area should be kept at a healthy distance away as an upset can cause deadly fumes to accumulate. 

The system resistance increases and discharge reduces at the same rated speed This condition refers to point B, to which the earlier point A, has now shifted. The system now operates at a higher head f/j2. whereas the actual head has not increased. This condition has occurred due to higher system resistance offered by the throttle. The pump and the prime-mover efficieticy will now reduce to 73 7r from its original 8.3%. 

A friction loss of 37.125 m In a total length of 1000 m is quite high and will require a larger motor. Therefore, a 150 mm main pipeline will offer a better and more economical design compared to a 125 mm pipeline such as the reduced cost of the prime mover and lower power consumption during the life of pumping system, in addition to a longer life span of a 150 mm pipe compared to a 125 mm pipe. 

When possible, gears should be run-in on initial startup. Speeds and loads should be inereased in pereentage inerements. Lube oil temperature, and pressure and bearing temperatures should be observed and adjustments made to the lube system as required. The number of adjustments made will depend on the eomplexity of the system. Oil pressure is of primary importanee. When an auxiliary pump has been provided, oil should be eireulated before the aetual start. If not, the pump should be primed, and the journals wetted with oil. Primer holes are sometimes provided or alternate journals ean be oiled through the holes provided for bearing temperature deteetors. 

The oil system should be equipped with a main oil pump, a standby and, for eritieal maehines, an emergeney pump. Eaeh pump must have its own driver, and eheek valves must be installed on eaeh pump diseharge to prevent reverse flow through idle pumps. The pump eapaeity of the main and standby pumps should be 10-15% greater than maximum system usage. The pumps should be provided with different prime movers. 

In nearly all mechanical power applications in the oil and gas industry it is necessary to transmit the power generated by a prime mover to an operation (e.g., drawworks of a drilling rig, or a production pumping system). The transmission of rotary power to such operation elements is carried out by a power transmission system. Mechanical power transmission is typically carried out by power betting systems, chain systems, gear systems and by hydraulic systems, or some combination of these three [1,5]. 

The total pump power input Ppi is the net power delivered to the pump drive shaft by the prime mover system. This is... 

The capacity of a pump is determined by the number of plungers or pistons and the size of these elements (bore and stroke). A reciprocating pump is usually designed for a specific volumetric rate capacity and pressure capability. These factors are set by the application. Once the volumetric rate capacity and pressure capability are known, a designer can determine the plunger piston bore and stroke the rotation speed range and the power of the prime mover needed to complete the system. 

Positive displacement pumps are self-priming by their normal operating action and are designed to cope with mnning dry. Centrifugal pumps are not inherently selfpriming, and need to be provided with assistance in the form of ejectors, as in Figure 32.56 or dry vacuum pump systems. In these systems, a dry vacuum pump allows air to be drawn out and where an automatic valve prevents... 

Safety systems should not be segregated together. Each safety system should be diversified as much as possible to avoid the possibility of a single point failure. A prime example is the firewater supply which should be pumped into a facility firemain at several separate and remote locations. 

Air intakes to heating and ventilation systems, air compressors for process, instrument and breathing air, and to prime movers for gas compressors, power generation and pumps should be located as far as practical from contamination by dust, toxic and flammable materials release sources. They should not be located in electrically classified areas. If close to possible vapor releases (as confirmed by dispersion analyses( they should be fitted with toxic or combustible gas detection devices to warn of possible air intakes hazards and snutdown and isolate the incoming air ductwork and fans. 

An air pocket in the pump can cause low or no pressure or flow, erratic pressure, and changes in retention time data. It may be necessary to bleed air from the pump or prime the pump according to system startup procedures. Air pockets in the column will mean decreased contact with the stationary phase and thus shorter retention times and decreased resolution. Tailing and peak splitting on the chromatogram may also occur due to air in the column. Air bubbles in the detector flow cell are usually manifested on... 

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