Tubing performance properties

Tubing performance properties, according to API Bulletin 5C2, 18th Edition (March 1982), are given in Table 4-167. Formulas and procedures for calculating the values in Table 4-167 are given in API Bulletin 5C3, 3rd Edition (March 1980). 

API Bulletin 5C2, Twentieth Edition API Bulletin on Performance Properties of Casing, Tubing and Drilling Pipe, May 1987. 

These standards cover the manufacture, testing, and performance of laminating thermosetting products in the form of sheets, rods, and tubes. The properties of NEMA-type laminates are described in Appendix E. 

After application, the liquid coating must be converted into a solid polymeric film (viscosity > 10 cps) in order to build up satisfactory performance properties (termed the film formation process) [74]. As water evaporates from a film of emulsion polymer, the distance of separation between the submicron particles continues to decrease and, ultimately, capillary tubes form. In a capillary tube, surface tension results in a force that tends to collapse the tube. Moreover, the smaller the diameter of the tube, the greater the destruction force. When the particles are so close to one another, the destruction force is strong enough to overcome the repulsion forces originating from either the electrostatic or steric interaction mechanism striving to push the neighboring particles apart. Coalescence of the particles to form a continuous film is thus possible. 

Doloma Graphite SENs. Doloma graphite (DG) pouring shrouds were developed in order to reduce and/or eliminate the tendency for alumina deposition in the SEN or SES. The DG tubes have been used primarily for casting stainless steels prone to alumina clogging and aluminum killed carbon steels that are also prone to this problem. Alumina graphite (AG) are typically used in these applications however, alumina deposition is usually the limiting factor for their performance. Properties for several DG materials are shown as compared to a typical AG material in Table 9. 

The development of Remote Field Eddy Current probes requires experience and expensive experiments. The numerical simulation of electromagnetic fields can be used not only for a better understanding of the Remote Field effect but also for the probe lay out. Geometrical parameters of the prohe can be derived from calculation results as well as inspection parameters. An important requirement for a realistic prediction of the probe performance is the consideration of material properties of the tube for which the probe is designed. The experimental determination of magnetization curves is necessary and can be satisfactory done with a simple experimental setup. 

Effect of Uncertainties in Thermal Design Parameters. The parameters that are used ia the basic siting calculations of a heat exchanger iaclude heat-transfer coefficients tube dimensions, eg, tube diameter and wall thickness and physical properties, eg, thermal conductivity, density, viscosity, and specific heat. Nominal or mean values of these parameters are used ia the basic siting calculations. In reaUty, there are uncertainties ia these nominal values. For example, heat-transfer correlations from which one computes convective heat-transfer coefficients have data spreads around the mean values. Because heat-transfer tubes caimot be produced ia precise dimensions, tube wall thickness varies over a range of the mean value. In addition, the thermal conductivity of tube wall material cannot be measured exactiy, a dding to the uncertainty ia the design and performance calculations. 

Common to all air cooled heat exchangers is the tube, through which the process fluid flows. To compensate for the poor heat transfer properties of air, which flows across the outside of the tube, and to reduce the overall dimensions of the heat exchanger, external fins are added to the outside of the tube. A wide variety of finned tube types are available for use in air cooled exchangers. These vary in geometry, materials, and methods of construction, which affect both air side thermal performance and air side pressure drop. In addition, particular... 

CE, another high performance separation technique, was also proved to be a powerful tool and an alternative for HPLC in the analysis of natural dyestuffs, even if its application in this field is still considerably limited. It could play an important role especially in the analysis of artworks, as it requires a very small volume of a sample solution (a few dozen nanolitres). In CE[ 10 14] separation of charged species is based on their different migration properties along the capillary tube which is in a constant electric field. Two platinum electrodes and both ends of a narrow bore (i.d. 25 100 pm) flexible fused silica capillary (usually 60 100 cm long) filled with a suitable conducting buffer are immersed in two... 

---