Write an account of tinning of copper vessels and Annodization of Aluminium articles.Also write an account of different type of Anodized vessels available in the market which are required for daily use
Answers
Answer:
Tinning is the process of thinly coating sheets of wrought iron or steel with tin, and the resulting product is known as tinplate. The term is also widely used for the different process of coating a metal with solder before soldering.[1]
Tin layer on the inside of a tin can
It is most often used to prevent rust, but is also commonly applied to the ends of stranded wire used as electrical conductors to prevent oxidation (which increases electrical resistance), and to keep them from fraying or unraveling when used in various wire connectors like twist-ons, binding posts, or terminal blocks, where stray strands can cause a short circuit.
While once more widely used, the primary use of tinplate now is the manufacture of tin cans. Formerly, tinplate was[clarification needed] used for cheap pots, pans, and other holloware. This kind of holloware was also known as tinware and the people who made it were tinplate workers.
The untinned sheets employed in the manufacture are known as black plates. They are now made of steel, either Bessemer steel or open-hearth. Formerly iron was used, and was of two grades, coke iron and charcoal iron; the latter, being the better, received a heavier coating of tin, and this circumstance is the origin of the terms coke plates and charcoal plates by which the quality of tinplate is still designated, although iron is no longer used. Tinplate was consumed in enormous quantities for the manufacture of the tin cans in which preserved meat, fish, fruit, biscuits, cigarettes, and numerous other products are packed, and also for the household utensils of various kinds made by the tinsmith.[2]
History Edit
The practice of tinning ironware to protect it against rust is an ancient one. According to Pliny the Elder tinning was invented by the Gallic Bituriges tribe (based near modern Bourges), who boiled copper objects in a tin solution in order to make them look as if they were made from silver.[3] The first detailed account of the process appears in Zosimus of Panopolis, Book 6.62, part of a work on alchemy written in Roman Egypt around 300 AD. Aside from an attestation in 14th century England, the process is not attested again in Europe until the description in Lazarus Ercker's Das Kleine Probierbuch (1556)[4]
The manufacture of tinplate was long a monopoly of Bohemia, but in about the year 1620 the industry spread to Saxony.[2] Tinplate was apparently produced in the 1620s at a mill of (or under the patronage of) the Earl of Southampton, but it is not clear how long this continued.
Andrew Yarranton, an English engineer and agriculturist, and Ambrose Crowley (a Stourbridge blacksmith and father of the more famous Sir Ambrose Crowley III) were commissioned to go to Saxony and if possible discover the methods employed.[2] They visited Dresden in 1667 and found out how it was made. In doing so, they were sponsored by various local ironmasters and people connected with the project to make the River Stour navigable. In Saxony, the plates were forged, but when they conducted experiments on their return to England, they tried rolling the iron. This led to two of the sponsors, the ironmasters Philip Foley and Joshua Newborough, erecting a new mill, Wolverley Lower Mill (or forge), in 1670. This contained three shops: one being a slitting mill, which would serve as a rolling mill, the others being forges. In 1678 one of these was making frying pans and the other drawing out blooms made in finery forges elsewhere. It is likely that the intention was to roll the plates and then finish them under a hammer, but the plan was frustrated by one William Chamberlaine renewing a patent granted to him and Dud Dudley in 1662. Yarranton described the patent as "trumped up".[5][6]
The slitter at Wolverley was Thomas Cooke. Another Thomas Cooke, perhaps his son, moved to Pontypool and worked there for John Hanbury (1664–1734).[7] According to Edward Lhuyd, by 1697, John Hanbury had a rolling mill at Pontypool for making "Pontypoole Plates" machine.[8][9] This has been claimed as a tinplate works, but it was almost certainly only producing (untinned) blackplate. However, this method of rolling iron plates by means of cylinders, enabled more uniform black plates to be produced than was possible with the old plan of hammering, and in consequence the English tinplate became recognised as superior to the German.[2]
Treforest tin works, Glamorganshire c. 1840
Tinplate first begins to appear in the Gloucester Port Books (which record trade passing through Gloucester, mostly from ports in the Bristol Channel) in 1725. The tinplate was shipped from Newport, Monmouthshire.[10] This immediately follows the first appearance (in French) of Réaumur's Principes de l'art de fer-blanc, and prior to a report of it being published in England.