Oilfields

The main problem associated with deep drilling, however, is that of stabilizing the wall of the drill hole. Depending on the geological properties of the rock formation, the wall of the hole may exhibit cracks. Water from the drilling fluid will then be forced into these cracks by the prevailing hydraulic pressure. In rock formations with a lai e proportion of clay this water causes the clay minerals to 

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Not surprisingly, costs are several times higher than conventional wells. Nevertheless, overall project economics may favour ERD over other development options. For example, BP developed the offshore part of the Wytch Farm Oilfield (which is located under Poole Harbour in Dorset, UK) from an onshore location. The wells targeted the reservoir at a vertical depth of 1,500 meters with a lateral displacement of over 8,000 meters (Fig. 3.20). The alternative was to build a drilling location on an artificial island in Poole Bay. ERD probably saved a considerable amount of money and advanced first oil by several years. 

For oilfield use, the x-axis on expectation curves is typically the STOIIP, GIIP, UR, or Reserves of a field. 

Oilfield applications Oil-field drilling Oilfield fluids Oil fields... 

Polyacrylamides are used in many other oilfield appUcations. These include cement additives for fluid loss control in well cementing operations (127), viscosity control additives for drilling muds (128), and fracturing fluids (129). Copolymers [40623-73-2] of acrylamide and acrylamidomethylpropanesulfonic acid do not degrade with the high concentrations of acids used in acid fracturing. 

S. Palumbo, D. Giacca, M. Ferrari, and P. Pirovano, Society of Petroleum Engineers International Symposium on Oilfield Chemistry, SPE 18477, Houston, Tex., Feb. 8-10,1989. 

Parts made from fluoroelastomers ate used ia appHcations that justify their high cost, usually where the maintenance and replacement costs are high enough to offset the initial cost of the part. These include automotive appHcations such as valve stem seals, fuel injector components, radiator, crankcase and transmission seals, and carburetor needle tips. Numerous seals and gaskets in the marine, oilfield, and chemical processing industries employ fluoroelastomers. In addition, many hoses in the automotive and chemical industry are made entirely of fluoroelastomer compounds or have a veneer of the fluoroelastomer as a barrier exposed to the harsh environment. Seals and gaskets in military appHcations and the binder for flares and missile appHcations ate made with fluoroelastomers. 

Vluorosilicone. By fluorinating the siHcone polymer molecule it is possible to improve the solvent, fuel, and oil resistance of this already heat-resistant class of elastomers. The resulting polymers are especially useful in select automotive seals and gaskets as weU as military and downhole oilfield parts. 

Sulfide Stress Cracking Resistant Metallic Materialfor OilField Equipment, NACE Standard MR-01-75, 1980 rev.. Technical Practices Committee, National Association of Corrosion Engineers, Houston, Tex., 1980. 

Oilfield Uses. Calcium chloride has two uses in the oilfield as a primary ingredient in completion fluids and as the brine phase in an invert emulsion oil mud. An excellent review of oil well drilling fluids is available (36) (see also Petroleum, drilling fluids). 

Since in oilfields or reservoirs borehole casings are frequently sited close to one another, they can be affected by the voltage cone of the anode bed and the cathodic voltage cone of other casings. Thus, in the case of large oilfields and reservoirs, it is appropriate to protect all wells cathodically. 

The average protection current requirement can be conveniently determined for individual wells in an oilfield by measuring the Tafel potential. In contrast to profile measurements, internal measurements on the casing are not necessary. These measurements cannot be used to predict polarization behavior at greater depths. 

Well casing and pipelines in oilfield Cathodic protection Bitumen coating 1.35... 

Francis S. Manning and Richard E. Thompson s Oilfield Processing of Petroleum, Volume One Natural Gas. Copyright Penn Well Books, 1991. 

Reciprocating compressors are available with a large variety of other drivers, which include the piston engine, steam turbine, or, in rare cases, a gas turbine. Next in popularity to the electric motor is the piston engine. The arrangement lends itself to skid mounting, particularly with the semi-portable units found in the oilfield. The unit is also popular as a lease unit, which may be lifted onto a flat bed trailer and moved from one location to another as needed. The engine is either direct-coupled or. as with smaller compressors, it may be belt-connected. 

The excellent chemical resistance of Aflas has led to important applications in oilfields and, more recently, in the car industry in place of FKM rubbers because of the better resistance to new types of engine oils, transmission fluids, gear lubricants and engine coolants. 

The American Petroleum Institute Manual on Disposal of Refinery Wastes provides specific design and construction standards for APTseparators that are often used in oilfield waste disposal [24],... 

Figure 2-58. Poisson s ratio vs. depth (from Eaton, Fracture Gradient Prediction and Its Application in Oilfield Operations, Journal of Petroleum Technology, October 1969).

Typical sizes and constructions of wire rope for oilfield service are shown in Table 4-30. Because of the variety of equipment designs, the selection of other constructions than those shown is justifiable. 

In oilfield service, wire rope is often referred to as wire line or cable. For clarity, these various expressions are incorporated in this recommended practice. 

Typical Sizes and Constructions of Wire Rope for Oilfield Service [12]... 

The large number of existing oilfield facilities operation in or discharging produced water into surface waters of the United States has prompted EPA to issue general NPDES permits. The general permit allows discharge of low-toxicity drilling fluid directly to the sea. 

Medium radius and long radius wells are drilled with conventional oilfield tools. Both MWD and LWD are usable in these wells. Downhole motors are mostly used in medium radius wells to avoid fatigue of the BHA. Long radius wells have been drilled with both mud motors and rotary techniques. 

In oilfield situations we are generally faced with corrosion attacks in aqueous environments. Basically all attacks in aqueous solutions are electrochemical in nature. This means that besides the chemical reaction there will also be a flow of electrons, resulting in a flow of current. The current flows from a higher potential to a lower one. Hence, there are two reactions taking place simultaneously in the system. One reaction occurs as the electrons are discharged from the surface, called the anode. The released electrons are consumed in the other... 

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