Surface pumping

The principle of operation of the hydraulic reciprocating pump is similar to the beam pump, with a piston-like sub-surface pump action. The energy to drive the pump, however, is delivered through a hydraulic medium, the power fluid, commonly oil or water. The power fluid drives a downhole hydraulic motor which in turn drives the pump. A separate surface pump delivers the hydraulic power. The power fluid system can be of the closed loop or of the open type. In the latter case, the power fluids are mixed with the produced fluid stream. The performance of the hydraulic pump is primarily monitored by measuring the discharge pressures of both surface and sub-surface pumps. 

Pesticides in air and on surfaces Pumped filters/sorbent tubes with gas chromatography 94... 

The dump valve is a very important feature of the positive displacement motor. The positive displacement motor does not permit fluid to flow through the motor unless the motor is rotating. Therefore, a dump valve at the top of the motor allows drilling fluid to be circulated to the annulus even if the motor is not rotating. Most dump valve designs allow the fluid to circulate to the annulus when the pressure is below a certain threshold, say below 50 psi or so. Only when the surface pump is operated does the valve close to force all fluid through the motor. 

Rather moderate flow rates and pressures are required to operate the positive displacement motor. Thus, most surface pump systems can be used to operate these downhole motors. 

When the rotor shaft of the positive displacement motor is not rotating, the surface pump pressure will rise sharply and little fluid will pass through the motor. 

In well engineering and applications, cement must be dealt with in both its slurry form and in its set form. At the surface the cement must be mixed and then pumped with surface pumping equipment through tubulars to a designated location in the well. After the cement has set, its structure must support the various static and dynamic loads placed on the well tubulars. 

The vacuum system must be able to attain the required pressures reliably despite these high gas loads. In the example shown, the system is evacuated with a combination of a backing and Roots pump. A diffusion pump along with a cold surface forms the high vacuum pump system. The cold surfaces pump a large portion of the vapor and volatile substances emitted by the plastic parts while the diffusion pump basically removes the non-condensable gases as well as the noble gas required for the sputter process. 

In theory, this is the greatest height that water can be lifted from a well by a surface pump. In practice, this maximum lift height is 25 to 30 ft. Of course, water is pumped from bore-hole wells hundreds of feet deep. But this is done by submersible pumps, which are let down into the well. 

This particular fermentation is performed in 1+00 liter batches. Tangential flow filtration was carried out with a Pe licon cassette (Millipore Corp.). The filtration area was 25 ft using a 100,000 molecular weight cut off ultrafiltration membrane. The inlet pressure was maintained at 1+0 psig while the outlet pressure was 25 psig and recirculation rates of the cell suspension were 3 5 GPM tangential to the upstream membrane surface. Pumping of the cell suspension was performed with a Moyno screw pump. 

Friction pressures and viscosities are two important physical characteristics of well stimulation fluids. Friction pressures, fluid hydrostatics and fracturing gradients determine the minimum surface pumping pressure necessary to maintain fracture growth. Often friction pressure is the de-... 

The holding tanks should be on a weekly maintenance schedule to check for wet regions in the bermed area. These may indicate leaks, but could also be from rain or condensate formed on exterior tank surfaces. Pumps and agitator motors should be checked and serviced on the same schedule as sampling and discharge. 

Gas entrainment studies are in progress taking into account identification of sources (free surface, pump shaft, spillway), behaviour and transport of bubbles (VIBUL computer code) possibility of gas pocket formation and removal. 

Weter Leekage When water from external sources enters the process side of the evaporator, thermal efficiency decreases since such leaks dilute the product and increase the amount of water to be evaporated. Possible sources of water leakage into the process are corroded heat-exchange surfaces, pump seal flushes, barometric condenser water flooding, condenser flushes, and leaking of the water valves used to clean out the evaporator for startup and shutdown. 

Because of the viscosity of the electrolyte solution and centrifugal action affecting the solution adhering to the rotating front surface, pumping action results with the liquid at the surface accelerated radially away (Fig. 2). 

Cathodic protection is widely used in classic and atomic power plants, oil refineries, chemical works, and for the protection of gas and water pipelines and other metal structures. Excellent results are obtained by this method during anticorrosion electrochemical protection of reactors, tanks, pipelines (external and internal surfaces), pumps, coolers, heat exchangers, etc. Con-... 

Lactate is freely transported from the cytosol through the plasma membrane to the environment where it decreases the bulk phase pH. This is one of the reasons why a Mycoplasma infection, so dreaded by those who culture cells, is harmful to them. These organisms are glycolytic engines [10] and adhere to the cell surface, pumping out lactate in relatively large amounts. 

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