ASME B31.5 pdf download

ASME B31.5 pdf download.Refrigeration Piping and Heat Transfer Components.
This Refrigeration Piping and feat Transfer Components Code is a Section of the American Society of Mechanical Engineers Code for Pressure Piping, 1331. This Section is published as a separate document for simplicity and for convenience of Code users. The users of this Code are advised that in some areas legislation may establish governmental jurisdiction over the subject matter covered by the Code. The owner of a piping installation shall choose which piping code(s) are applicable to the installation and shall have the overall responsibility for compliance with this Code. (See Nonmandatory Appendix C.) The owner of a complete piping installation shall have the overall responsibility for compliance with this Code.
It is required that the engineering design specify any special requirements pertinent to the particular service involved. For example, the engineering design shall not for any service specify a weld quality lower than that stipulated in para. 527.3.2(d) for the Code-required visual examination quality and for the types of welds involved; but where service requirements necessitate added quality and more extensive nondestructive examination, these are to be specified in the engineering design and any revision thereto, and when so specified, the Code requires that they be accomplished.
The Code generally employs a simplified approach for many of its requirements. A designer may choose to use a more complete and rigorous analysis to develop design and construction requirements. When the designer decides to take this approach, the designer shall provide details and calculations demonstrating that design, contruction, examination, and testing are consistent with the criteria of this Code. The details shall be documented in the engineering design.
500.1 Scope
Rules for this Code Section have been developed considering the needs for applications that include piping and heat transfer components for refrigerants and secondary coolants.
For pipe and tube that do not contain longitudinal or spiral joints, the Table shows the basic allowable stress, S. It is the allowable hoop stress.
For pipe and tube that do contain longitudinal or spiral joints, the Table shows the product, SE. of the basic allowable stress, S. and the longitudinal or spiral joint factor, E. SE is the allowable hoop stress.
For materials for which Table 502.3.1 shows longitudinal or spiral joint factors, C, divide the SE value shown in the Table above by the joint factor, E, to get the allowable stress, S. for Code computations in Part 5, Chapter II, where the joint factor, E, need not be considered.
The stress values in this Table are grouped according to temperature, and in every case the temperature is the metal temperature. The stress values in this Table may be interpolated to determine values for intermediate temperatures. Allowable stresses for materials not listed shall not exceed those determined using the basis in (b) for ferrous materials and in (c) for nonferrous materiaLs.
(b) The basis of establishing basic allowable stress values for ferrous materials in this Code is as follows.
The mechanical properties for materials as developed by the ASME 131’V Code were used for establishing stress values.
At 100°F (38°C) and below, an allowable stress value was established at the lower value of stress obtained from using 29% of the specified minimum tensile strength at room temperature, or 67% of the specified minimum yield strength for 0.2% offset at room temperature.
At temperatures above 100°F (38°C) hut below 400°F (205°C), allowable stress values were established that did not exceed 67% of the average expected yield strength for 0.2% offset at temperature, or did not exceed 29% of the average expected tensile strength at temperature.
(c) The basis for establishing basic allowable stress values for nonferrous materials in this Code is as follows.
The basic allowable stress values for temperatures over 100°F (38°C) determined as the lowest of the following when the tensile and yield strengths are obtained from standard short-time tests made at the temperature under consideration:
(ii 29% of the tensile strength as adjusted to minimum
(2) 67% of the yield strength as adjusted to minimum
(3) the stress producing a creep rate of 0.01% in 1,000 hr
(4) the stress producing rupture in 100,000 hr
At 100°F (38°C) and below, an allowable stress value was established at the lowest value of stress obtained by using 29% of the specified minimum tensile strength at room temperature, or 67% of specified minimum yield strength at room temperature.