History plumbing

The word "plumber" dates from the Roman Empire. [2] In Roman times lead was known as plumbum in Latin which is why the periodic table of the elements uses the symbol of 'Pb' for lead. Roman roofs used lead in conduits and drain pipes[3] and some were also covered with lead, lead was also used for piping and for making baths.[4] In medieval times anyone who worked with lead was referred to as a plumber as can be seen from an extract of workmen fixing a roof in Westminster Palace and were referred to as plumbers "To Gilbert de Westminster, plumber, working about the roof of the pantry of the little hall, covering it with lead, and about various defects in the roof of the little hall".[5] Thus a person with expertise in working with lead was first known as a Plumbarius which was later shortened to plumber.

Plumbers install and repair pipes, fittings, fixtures, and other plumbing equipment used for water distribution, waste water disposal, and venting in residential, commercial, institutional, and industrial buildings. Many plumbers begin their careers in plumbing as helpers to established plumbers; others enter formal training institutes.
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Some needed skills, interests, and values
• Reading blueprints, drawings, and specifications to determine layout of water supply, waste, and venting systems
• Installing, repairing and maintaining domestic, commercial, and industrial plumbing fixtures and systems
• Locating and marking positions for pipe connections, passage holes, and fixtures in walls and floors
• Measuring, cutting, bending, and threading pipes using hand and power tools or machines
• Testing pipes for leaks using air and water pressure gauges
• Awareness of legal regulations and safety issues

Welding

Welding is a fabrication or sculptural process that joins materials, usually metals or thermoplastics, by causing coalescence. This is often done by melting the workpieces and adding a filler material to form a pool of molten material (the weld pool) that cools to become a strong joint, with pressure sometimes used in conjunction with heat, or by itself, to produce the weld. This is in contrast with soldering and brazing, which involve melting a lower-melting-point material between the workpieces to form a bond between them, without melting the workpieces.
Many different energy sources can be used for welding, including a gas flame, an electric arc, a laser, an electron beam, friction, and ultrasound. While often an industrial process, welding can be done in many different environments, including open air, under water and in outer space. Regardless of location, however, welding remains dangerous, and precautions are taken to avoid burns, electric shock, eye damage, poisonous fumes, and overexposure to ultraviolet light.
Until the end of the 19th century, the only welding process was forge welding, which blacksmiths had used for centuries to join iron and steel by heating and hammering them. Arc welding and oxyfuel welding were among the first processes to develop late in the century, and resistance welding followed soon after. Welding technology advanced quickly during the early 20th century as World War I and World War II drove the demand for reliable and inexpensive joining methods. Following the wars, several modern welding techniques were developed, including manual methods like shielded metal arc welding, now one of the most popular welding methods, as well as semi-automatic and automatic processes such as gas metal arc welding, submerged arc welding, flux-cored arc welding and electroslag welding. Developments continued with the invention of laser beam welding and electron beam welding in the latter half of the century. Today, the science continues to advance. Robot welding is becoming more commonplace in industrial settings, and researchers continue to develop new welding methods and gain greater understanding of weld quality and properties.

Pipe fitting/ Gas fitting

Pipe fitting is the occupation of installing or repairing piping or tubing systems that convey liquid, gas, and occasionally solid materials. This work involves selecting and preparing pipe or tubing, joining it together by various means, and the location and repair of leaks.
Pipe fitting work is done in many different settings: HVAC, manufacturing, hydraulics, refineries, computer chip fab plants, power plant construction and other steam systems.
Fitters work with a variety of pipe and tubing materials including several types of steel, copper, iron, plastic, aluminium. Pipe fitting is not plumbing, the two are related but separate trades. Pipe fitters who specialize in fire prevention are called Sprinklerfitters, another related, but separate trade.
A pipefitter (also called steamfitter) is a tradesman who lays out, assembles, fabricates, maintains and repairs mechanical piping systems. Pipefitters usually go through a mix of apprentice and trade school training. Journeyman pipefitters/steamfitters deal with industrial process piping and heating/cooling systems. Typical industrial process pipe is under high pressure, which requires metals such as carbon steel, stainless steel, and many different alloy metals fused together through precisely cutting, threading, grooving, bending and welding, whereas a plumber concentrates on piping systems for heating/cooling as well as utility liquids potable water, sewage, drains, etc. in the industrial/commercial/institutional or residential atmosphere operating at lower pressures. Utility piping typically consists of copper, PVC, CPVC, polyethylene, and galvanized pipe which is typically glued, soldered, or threaded. Other types of piping systems include steam, ventilation, hydraulics, chemicals or fuel.[1]