Corrosion telecommunications

In 1929, an international commission, the Commission Mixte Internationale pour les experiences relatives a la protection des lignes de telecommunication et des canalisations souterraines (C.M.I.), was enlarged and its scope extended for the purpose of making experimental studies concerning the corrosion of pipes and cables. The C.M.I. membership was composed of international technical experts from learned bodies, research laboratories and manufacturers of electrical equipment, and representatives of authori-... 

These terms are derived from various sources, principally from the List of Definitions of Essential Telecommunications Terms (Part I, Corrosion), International Telecommunications Union, Geneva, 1957, 1st Supplement, I960, and the B.S.I. Code of Practice for Cathodic Protection, CP102I 1973 terms taken from the Code of Practice are marked with an asterisk. 

Magnesium is a very important metal that may have great applications in portable microelectronics, telecommunications, and aerospace industries, due to its low density. However, a poor corrosion resistance of magnesium limits its applications. On the other hand, coating of magnesium surfaces with other metals via electroless deposition can be quite difficult due to its reactivity with the most of the plating solutions. 

Utilities Utilities consist of gas, water, electricity, and telecommunications services and account for the largest portion of industrial corrosion costs. The total direct corrosion costs amount to 47.9 billion. These costs are partitioned into sectors of gas distribution, drinking water and sewer systems, electrical utilities, and telecommunications (Fig. 2.4). 

This sector describes the impact of corrosion on the telecommunications infrastructure. Telecommunications hardware consists of switch boards, electronics, computers, data transmitters, and receivers. Delicate electronic components... 

Most of the telecommunication hardware is placed and used in buildings and thus not exposed to corrosive atmosphere. In addition, electronic hardware has a limited lifetime and becomes obsolete in a few years. The actual service life of consumer is often limited by rapid technological changes rather than material degradation issues. 

Telecommunication equipment with a longer design life consists of cables, connectors, and antennas for the transmission and reception of electronic signals. These components may be placed and buried so that they become exposed to environments such as soils and water or they may be exposed to air and moisture conditions. There is no report on the percentage of failures because of corrosion for each category. 

A large majority of telecommunication towers are of the self-supporting type. These have been constructed since the early 1960s and are made from hot-dipped galvanized steel. For about 40 years, there is hardly any corrosion. 

The copper cables used in the telecommunications industry s electrical supply are encapsulated in plastic to prevent electrical shorts. The plastic cover also provides corrosion protection to the wires. The following anticorrosion protection measures are recommended ... 

Telecommunications hardware consists of switchboards, electronics, computers, data transmitters, and receivers. Delicate electronic components must be protected from human actions and weather for smooth operation over long periods of time. Most failures of this type of equipment are caused by environmental factors. If left unprotected from moisture, corrosion of delicate small parts results in malfunction. Most of the telecommunications hardware is placed in buildings and hence are not exposed to corrosive environments. Telecommunications equipment with a longer design life such as cables, connectors, and antennas may be placed outside and buried and are exposed to soils, water, air, and moist weather conditions. 

A wet cell battery has a liquid electrolyte. It is also called as flooded cell, since the liquid covers all internal parts. Wet cells were a precursor to dry cells and are commonly used as a tool for electrochemistry. A particular type of wet cell known as a concentration cell is important in imderstanding corrosion. Wet cells may be primary or secondary cells. Some other primary wet cells are the Leclanche cell. Grove cell, Bunsen cell, chromic acid cell, etc. Wet cells are used in automobile batteries and telecommunication. 

In the past the copper conductor pairs in telecommunication cables were insulated with paper pulp, and the outer sheath, which serves as an electric shield and provides corrosion-resistant physical protection, was made of a lead alloy containing 1.0 mass% antimony. The connections (splices) between the individual conductors were enclosed either in lead sleeves or in closures consisting of two galvanized half shells of gray cast iron, held together with stainless steel bolts and nuts. Although there is still a considerable amount of lead-sheath cable, lead sleeves, and galvanized cast iron closures, the modem telecommunication cable plant relies heavily on plastics as the material of constmction. 

---