Lead Cable Sheathing Alloys

Copper and Copper Alloys 296 3.1.11.9 3.1.11.10 Lead Cable Sheathing Alloys Other Lead Alloys A21 A21... 

The applications of arsenic as a metal are quite limited. Meialluigically, it is used mainly as an additive. The addition of from to 2% of arsenic improves the sphericity of lead shot. Arsenic in small quantities improves the properties of lead-base bearing alloys for high-temperature operation. Improvements m hardness of lead-base battery grid metal and cable-sheathing alloys can be obtained by slight additions of arsenic. Very small additions (0.02 - 0.05%) of arsenic to brass reduce dezincdfication. 

Lead is soft and malleable, and possesses an excellent resistance to corrosion. It has been used for water pipework and waste disposal systems, but nowadays is replaced by other materials. A major application for lead is in the manufacture of lead-acid storage batteries which account for almost 30% of the annual world consumption of lead. Cable sheathing, soft solders, and fusible plugs in the sprinklers of fire-fighting systems are other applications of lead alloys (see Table 4.14). 

Only lead alloys containing copper below 0.08% have practical appHcations. Lead sheet, pipe, cable sheathing, wine, and fabricated products are produced from lead—copper alloys having copper contents near the eutectic composition. Lead—copper alloys in the range 0.03—0.08 wt % copper are covered by many specifications ASTM B29-92 (7), QQL 171 (United States), BS 334, HP2 Type 11 (Canada), DIN 1719 (Germany), and AS 1812 (Austraha). 

Lead—copper alloys are the primary material used in the continuous extmsion of cable coverings for the electrical power cable industry in the United States. Other alloys, containing tin and arsenic as well as copper, have also been developed for cable sheathing in the United States to provide higher fatigue strength. 

The major uses are in metallurgy, primarily as an additive to lead, copper, brass and many lead-base bearing alloys to improve their mechanical and thermal properties. Small amounts are added to lead in the manufacture of lead shot to improve its sphericity also added to lead-base cable sheathing and battery grid metal to improve hardness. Addition of very small quantities to copper enhances the corrosion resistance. It prevents cracking in brass. 

Lead acid batteries solder alloys cable sheathing pigment rust inhibitors ammunition glazes plastic stabilizers antiknock compounds in petrol plumbing fittings solder lead pipes 23, 3513,3529, 353,361,372, 38... 

Sb and Cu. Its resistance to atmospheric corrosion and to attack by acids leads to employment in chemiceil plant, for pipes and cable sheathing. The presence of 0.050—0.065% of tellurium improves the properties desirable for thes(i purposes, such as grain-size, hardness, tensile strength and corrosion resistance. Alloyed with a little Sb, it is used in large quantities for the electrode grids in lead-acid storage batteries. 

Use Hardening alloy for lead, especially storage batteries and cable sheaths bearing metal type metal solder collapsible tubes and foil sheet and pipe semiconductor technology (99.999% grade) pyrotechnics. 

The lead is often alloyed with small amounts of tin and antimony to improve its ability to withstand mechanical fatigue, such as fatigue experienced in long distance transportation to site. Lead sheathed cables should not be installed where regular cyclic physical movement will be experienced. Table 9.4 shows some of the electrical properties of metallic lead used for sheathing cables. 

Antimony/lead alloys are used in bearings and electrical cable sheathing. 

Uses Metallic form Alloying additive for metals, esp. lead and copper as shot, battery grids, cable sheaths High-purity semiconductor grade Mfg. of gallium arsenide for dipoles and other electronic devices doping agent solders medicine... 

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