AWS F4.2:2020 pdf free download

AWS F4.2:2020 pdf free download.Safety Guidelines for Proper Selection of Welding Cables.
(2) For long cable runs on construction sites, aluminum may he chosen for ease of handling. Aluminum is less than one-third the density of copper. but has less than twice the resistivity, so a cable capable of carrying the same current is lighter.
6.3.2 As noted in 6.2, the resistivity of aluminum is greater than that ot copper. A capacity table specifically for aluminum (such as Table B2 in Annex B) must be used to size conductors. Aluminum may he coated with copper to decrease oxidation and improve contact resistance, and so will be copper colored, but its electrical resistance remains that of aluminum.
6.3.3 Aluminum conductors are susceptible to oxidation at joints, which can lead to loosening, increased resistance. and overheating. For this reason, special devices and techniques are required when assembling aluminum cable sysLems. Users should refer to specific standards such as Section 110.14 of NFPA 70. National Electrical Code.
7. Insulation Materials
7.1 Several insulation material types are suitable for use on welding cables. The choice of insulation is generally specified by the equipment manufacturer or the end-user but can be substantially impacted by the work environment.
(I) Ethylene propylene rubber (EPR), ethylene propylene diene monomer (EPDM) and chlorinated polyethylene (CPE) are synthetic rubber materials, most widely used in heavy industrial applications. The advantages of synthetic rubber are better abrasion and chemical resistance, extreme temperature ranges [typically —58°F to 194°F (—50°C to 90°C) or 22 1°F (105°C)1, and superior resistance to slag and spatter.
(2) Thermoplastic elastomers (TPE) and polyvinyl chloride (PVC) are synthetic plastic materials, widely used in light industrial applications. The advantages of synthetic plastic are lighter weight cables which slide more easily on metal. They are, however, less flexible than synthetic rubber cables, do not perform as well in extreme temperature ranges and are more prone to tears in the insulation.
7.2 All insulation materials should he flame retardant (as indicated in NFPA 70, Article 630) and self-extinguishing.
7.3 The cable insulation should have the appropriate temperature rating for the work environment.AWS F4.2:2020 pdf free download.