Piping nonmetals

Nonmetals The following are specific considerations to be evaluated when applying certain nonmetals in piping ... 

Table 10-56 gives values for the modulus of elasticity for nonmetals however, no specific stress-limiting criteria or methods of stress analysis are presented. Stress-strain behavior of most nonmetals differs considerably from that of metals and is less well-defined for mathematic analysis. The piping system should be designed and laid out so that flexural stresses resulting from displacement due to expansion, contraction, and other movement are minimized. This concept requires special attention to supports, terminals, and other restraints. 

Displacement Strains The concepts of strain imposed by restraint of thermal expansion or contraction and by external movement described for metallic piping apply in principle to nonmetals. Nevertheless, the assumption that stresses throughout the piping system can be predic ted from these strains because of fully elastic behavior of the piping materials is not generally valid for nonmetals. 

Elastic Behavior The assumption that displacement strains will produce proportional stress over a sufficiently wide range to justify an elastic-stress analysis often is not valid for nonmetals. In brittle nonmetallic piping, strains initially will produce relatively large elastic stresses. The total displacement strain must be kept small, however, since overstrain results in failure rather than plastic deformation. In plastic and resin nonmetallic piping strains generally will produce stresses of the overstrained (plasfic) type even at relatively low values of total displacement strain. 

Table A-2 Boiling and freezing point properties 843 Table A-3 Properties of solid metals 844 846 Table A-4 Properties of solid nonmetals 847 Table A-5 Properties of building materials 848-849 Table A-6 Properties of insulating materials 850 Table A-] Properties of common foods 851-852 Table A-8 Properties of miscellaneous materials 853 TableA-9 Properties of saturated water 854 Table A 10 Properties of saturated refrigerant-134a 855 Table A-11 Properties of saturated ammonia 856 Table A-12 "Properties of saturated propane 857 Table A-13 Properties of liquids 858 Table A-14 Properties of liquid metals 859 Table A- 5 Properties of air at 1 atm pressure 860 TableA-16 Properties of gases at 1 atm pressure 861-862 Table A-17 Properties of the atmosphere at high altitude 863 Table A-18 Emissivities of surfaces 864-865 Table A-19 Solar radiative properties of materials 866 Figure A-20 The Moody chart for friction factor for fully developed flow in circular pipes 867...

Metals are distinguished from nonmetals by their strength, toughness, electrical conductivity and thermal conductivity. However, the dominant property that causes metals to be preferred over most nonmetals is their ability to deform in the presence of excessive stress rather than fracture catastrophically. This is the prime reason for the widespread use of metals for structural applications such as plant equipment, piping and pressure vessels. 

A Figure 2.17 Some familiar examples of metals and nonmetals. The non metals (from bottom left) are sulfur (yellow powder), iodine (dark, shiny crystals), bromine (reddish brown liquid and vapor in glass vial), and three samples of carbon (black charcoal powder, diamonds, and graphite in the pencil lead). The metals are in the form of an aluminum wrench, copper pipe, lead shot, silver coins, and gold nuggets. 

Corrosion Protection Handbook Second Edition, Revised and Expanded, edited by Philip A. Schweitzer Corrosion Resistant Coatings Technology, Ichiro Suzuki Corrosion Resistance of Elastomers, Philip A. Schweitzer Corrosion Resistance Tables Metals, Nonmetals, Coatings, Mortars, Plastics, Elastomers and Linings, and Fabrics Third Edition, Revised and Expanded (Parts A and B), Philip A. Schweitzer Corrosion-Resistant Piping Systems, Philip A. Schweitzer Corrosion Resistance of Zinc and Zinc Alloys Fundamentals and Applications,... 

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