The size of casing is expressed as a nominal diameter, meaning that is the designated or theoretical outside diameter of the pipe. API and ISO allow for some tolerance in that measurement, and the specific tolerance differs for different size pipe. The tolerances for nonupset casing 4-1/2 in. and larger are given as fractions of the outside diameter in Table …

Nominal pipe size (NPS) is used to describe a pipe by name only. It is essentially a “reference” size and does not translate to an exact diameter measurement of pipe 12″ and smaller. In process piping the term nominal simply refers to the name of the pipe, much like a 2″ × 4″ piece of lumber.

ASME Piping Code: The pipe diameter is identified by a dimensionless number called “nominal pipe size” or nominal diameter expressed in “nominal inches,” for example, NPS ½, ¾, 1, 11 / 4, 1 1 / 2, 2, 3, and 4 nominal inches. There is no direct correlation between the NPS and the actual pipe OD up to and including 12 in. After 12 in., the NPS is the actual OD. For example, the …

Major diameter, denoted by d, is the largest (outside) diameter of a screw thread. Minor diameter, denoted by dr or d1, is the smallest diameter of a screw thread. Pitch diameter, denoted by dm or d 2, is the imaginary diameter for which the widths of the threads and the grooves are equal.

The inside diameter of the casing determines the wall thickness or vice versa. Rather than a specific tolerance for the amount at which the internal diameter might exceed a nominal value, the tolerance specified by API and ISO is given in terms of minimum wall thickness. The minimum wall thickness is 87.5% of the nominal wall thickness.

Hole size vs. hole number For a multi-hole injector, the injector hole size usually refers to the nominal diameter of the channel connecting the in-cylinder charge and the sac volume, the volume right behind the needle seat in the injector.

Moreover, the reaction dynamics of the electrode are closely related to the pore structure of a porous electrode, and pore size is the most important parameter [11]. Pore size means the nominal diameter of the pores in a material. Generally, it refers to the average or the equivalence.

2003年6月1日 · Objectives Nominal size remains the standard by which valves are compared, but its relationship with orifice area and the patient tissue annulus diameter may differ according to valve design. The aims of this study were to measure the orifice size and compare biologic equivalence in six bileaflet mechanical heart valve designs.

The number of cracks decreased and there is an enhancement in the crack width with the bar diameter increase. Maranan et al. [103] investigated the effect of GFRP nominal bar diameter on the flexural and serviceability criteria of the GPC beams using three variations in bar diameter i.e., 12.7 mm, 15.9 mm, and 19 mm.

It assumes a cylindrical pore or capillary of varying diameter through the thickness of the scaffold and measures only its smallest diameter (throat diameter). Typically, the bubble point (largest throat diameter) and the mean flow pore diameter (50% flow) are determined.