Lifting techniques

There will be some uncertainty as to the well initials, since the exploration and appraisal wells may not have been completed optimally, and their locations may not be representative of the whole of the field. A range of well initials should therefore be used to generate a range of number of wells required. The individual well performance will depend upon the fluid flow near the wellbore, the type of well (vertical, deviated or horizontal), the completion type and any artificial lift techniques used. These factors will be considered in this section. 

Figure 9.18 provides an overview of the application envelope and the respective advantages and disadvantages of the various artificial lift techniques. As can be seen, only a few methods are suited for high rate environments gas lift, ESP s, and hydraulic systems. Beam pumps are generally unsuited to offshore applications because of the bulk of the required surface equipment. Whereas the vast majority of the world s artificially lifted strings are beam pumped, the majority of these are stripper wells producing less than 10 bpd. 

Artificial lift techniques are discussed in Section 9.6. During production, the operating conditions of any artificial lift technique will be optimised with the objective of maximising production. For example, the optimum gas-liquid ratio will be applied for gas lifting, possibly using computer assisted operations (CAO) as discussed in Section 11.2. Artificial lift may not be installed from the beginning of a development, but at the point where the natural drive energy of the reservoir has reduced. The implementation of artificial lift will be justified, like any other incremental project, on the basis of a positive net present value (see Section 13.4). 

The films were deposited onto solid substrates by a horizontal lift technique. One layer was deposited for the gravimetric and fluorescence measnrements. Twenty layers were deposited for x-ray stndy. 

Several studies have been made of LB films of esters of naturally occurring polysaccharides. Kawaguchi et al. [242] formed long chain esters of cellulose which, however, could only be formed into multilayers by the horizontal lifting technique. Schoondorp et al. [243] studied LB multilayers of esters of amylose and showed that materials with short alkyl side chains have a helical conformation at the air/water interface and that this structure can be transferred into multilayers. As in the case of the isotactic polymethylmethacrylate, the helical structure appears to lead to an oriented structure in the LB film. These two families of materials are illustrated in Figure 5.9. 

M. D. Cole, N. Ross, and J. W. Thorpe, Gunshot Residue and Bullet Wipe Detection Using a Single Lift Technique, AFTE Journal 24, no. 3 (July 1992) 254. 

Webb, C., Biomass Holdup in Immobilized Cell Reactors, Chap. 8 in Process Engineering Aspects of Immobilized Cell Systems, pp. 117-133. Instn. Chem. Engrs. (London), 1986. Weber, G., New Lift Technique, Oil Gas J., IS (1952). 

The gas-lift technique was adopted in two commercial processes the Houdriflow process, developed by Houdry Process Corporation (86), and the Air-Lift TCC process, developed by the Soeony-Vacuum Oil Company (107,333). 

Fig. 33. When the monolayers are transferred onto a gold substrate - at a surface pressure pertaining to the situations evidenced in Fig. 32a and b - by a horizontal lifting technique, a the tetracationic [2]catenanes can be seen to form a monolayer insulated from the gold surface by virtue of the aliphatic counterions, b The hexacationic [2]catenanes - less insulated from the gold surface - exhibit a linear current/voltage profile upon an applied potential, indicating their coupling to the gold surface...

Another way to reduce the mobility is by forming two-dimensional monolayers under ambient conditions. Adsorbate-substrate and adsorbate-adsorbate interactions lower the molecular mobility and are responsible for the two-dimensional ordering, Dry monolayers can be formed by drop casting and evaporation or by the horizontal lifting technique.It is also possible to measure... 

The back is the most frequently injured part of the body. Most safety and health programs strongly emphasize instruction on how to lift without hurting the back. Back injuries are often due to poor lifting techniques. Being out of shape makes it easier to incur a back injury. Once the back is injured, it becomes more prone to being injured again. 

And, unfortunately, no controlled epidemiological study has validated any of the contemporary theories on (lift techniques). 

There is a need for debate and a learned paper on manual lifting techniques, reflecting NIOSH research and other studies that put past practices in doubt. Valid guidelines for training on manual material handhng should be included in the paper. 

Back safety and lifting techniques is a topic that is not specifically regulated. The General Duty Clause, while not specifically requiring back safety as a topic for safety programs in any way, has been used as a means of enforcement against employers whose employees were subject to repetitive injiuies due to poor safety practices relative to a safety or health topic. 

---