Brass, 228 table

The use of Nansen bottles has some disadvantages, one being based on their construction. The closing mechanism impairs flushing of the sampler due to dead volumes and turbulent mixing. Modern samplers of the Nansen type are usually made of plastic materials such as polycarbonate (PC) and poly (vinyl chloride) (PVC) instead of brass (Table 1-2). Such samplers are less robust, but lighter, they are non-corrosive, greasing of the valves becomes unnecessary and interference with sample composition is minimized. 

Gluodenis describes the use of ICP to analyze samples containing Pb and Ni in brass. The analysis for Pb uses external standards prepared from brass samples containing known amounts of lead. Results are shown in the following table. ... 

What is the %w/w Pb in a sample of brass that gives an emission intensity of 9.25 X lO" The analysis for Ni uses an internal standard. Results for a typical calibration are shown in the following table. ... 

Fluorine can be handled using a variety of materials (100—103). Table 4 shows the corrosion rates of some of these as a function of temperature. System cleanliness and passivation ate critical to success. Materials such as nickel, Monel, aluminum, magnesium, copper, brass, stainless steel, and carbon steel ate commonly used. Mote information is available in the Hterature (20,104). 

Zinc consumption is categorized in five semifabricating markets (see Table 15). Galvanizing was the main market for zinc in the 1970s followed by zinc-base casting alloys and brass and bronze. Depressed constmction and automotive industries caused a decline from 1979 to 1980 of ca 18%, and the die-casting business declined 34% and galvanizing 24%. 

Phosphorized deoxidized arsenical copper (alloy 142 (23)) is used for heat exchangers and condenser tubes. Copper-arsenical leaded Muntz metal (alloy 366), Admiralty brass (alloy 443), naval brass (alloy 465), and aluminum brass (alloy 687), all find use in condensers, evaporators, ferrules, and heat exchanger and distillation tubes. The composition of these alloys is Hsted in Table 5. 

Table 16 illustrates the property enhancements and tradeoffs seen when tin is added to a copper—zinc brass base composition. The most commonly used alloys for electrical connectors are the Cu—10 Zn—Sn brasses, such as C411, C422, and C425. These lower level zinc—tin alloys offer good corrosion resistance along with the good formabiHty, conductivity, and strength levels of brass. 

Table 16. Conductivity and Wrought Tensile Strength of Tin-Brasses Showing the Hardening Effect of Tin Additions...

This computation is also referred to as calculating the zinc equivalent of the alloy. The increase in strength in this alloy series is caused by increased amounts of beta phase in the stmcture. The silicon brasses show similar hardening effects accompanying a second phase. Typical mechanical properties and electrical conductivity for various cast alloys are shown in Table 2. 

Properties of red brass alloys are given in Table 9. The members of this group are cast using the centrifugal, continuous, investment, and sand molding methods. General tensile strengths vary from 170 to 210 MPa (25,000—30,000 psi) minimum as cast in sand molds. 

Table 11. Properties of High Strength Yellow Brass ...

Table 13. Properties of Silicon Bronze and Silicon Brass Alloys...

Table 14. Properties of Copper-Nickel Alloys and Leaded Nickel Bronze and Brass...

TABLE 10-33 Copper and Red-Brass Pipe (ASTM B42 and B43) Standard Dimensions/ Weights/ and Tolerances... 

As you can see from the tables in Chapter 1, few metals are used in their pure state -they nearly always have other elements added to them which turn them into alloys and give them better mechanical properties. The alloying elements will always dissolve in the basic metal to form solid solutions, although the solubility can vary between <0.01% and 100% depending on the combinations of elements we choose. As examples, the iron in a carbon steel can only dissolve 0.007% carbon at room temperature the copper in brass can dissolve more than 30% zinc and the copper-nickel system - the basis of the monels and the cupronickels - has complete solid solubility. 

Plain tubes (either as solid wall or duplex) are available in carbon steel, carbon alloy steels, stainless steels, copper, brass and alloys, cupro-nickel, nickel, monel, tantalum, carbon, glass, and other special materials. Usually there is no great problem in selecting an available tube material. However, when its assembly into the tubesheet along with the resulting fabrication problems are considered, the selection of the tube alone is only part of a coordinated design. Plain-tube mechanical data and dimensions are given in Tables 10-3 and 10-4. 

For most practical purposes, the onset of plastic deformation constitutes failure. In an axially loaded part, the yield point is known from testing (see Tables 2-15 through 2-18), and failure prediction is no problem. However, it is often necessary to use uniaxial tensile data to predict yielding due to a multidimensional state of stress. Many failure theories have been developed for this purpose. For elastoplastic materials (steel, aluminum, brass, etc.), the maximum distortion energy theory or von Mises theory is in general application. With this theory the components of stress are combined into a single effective stress, denoted as uniaxial yielding. Tlie ratio of the measure yield stress to the effective stress is known as the factor of safety. 

The results of tests on copper alloys have been given by Tracy , Thompson , Mattsson and Holm and Scholes and Jacob , the first two of these investigations being made under the aegis of the American Society for Testing and Materials. The tests of Tracy, and Scholes and Jacob were both for periods up to 20 years in those of Thompson, and Mattsson and Holm specimens have been removed after 2 years and 7 years and further specimens remain exposed for removal after 20 years. The numbers of materials tested are given in Table 4.11 they included brasses, nickel silvers, cupro-nickels, beryllium coppers and various bronzes. Mattsson and Holm tested 14 alloys in the form of rod in addition to the sheet materials, the results for which are given in Table 4.11. 

In the tests described by Tracy, a high-tensile brass suffered severe dezinc-ification (Table 4.11). The loss in tensile strength for this material was 100% and for a non-arsenical 70/30 brass 54% no other material lost more than 23% during 20 years exposure. In Mattsson and Holm s tests the highest corrosion rates were shown by some of the brasses. Dezincification caused losses of tensile strength of up to 32% for a P brass and up to 12% for some of the a-P brasses no other materials lost more than 5% in 7 years. Dezinc-ification, but to a lesser degree, occurred also in the a brasses tested, even in a material with as high a copper content as 92%. Incorporation of arsenic in the a brasses consistently prevented dezincification only in marine atmospheres. 

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