Unit V. Forms of materials

A. Starting point

• What forms of materials do you know?

• What peculiarities of any materials are you aware of?

• Does the quality of a finished product depend on the materials?

Working with words

I. Study the table and think of the Russian equivalents

1. Bag	generally made of paper, linen, canvas, rubber, or plastic.
2. Sack	a larger, strong version of a bag usually made of jute.
3.Carton	made of light but strong cardboard, or fibreboard, it has double lids and bottoms which are fixed together.
4. Box	stronger than a carton, made of wood, cardboard or metal, sometimes with a folding (hinged) lid.
5.Case	a strong container made of wood. For extra strength, cases may have battens fixed to their tops, bottoms and sides.
6.Crate	this is like a case, but is not fully enclosed. It has a bottom and a frame, and is sometimes open at the top.
7.Container	a very large, robust, metal construction, varying in length from about ten to about forty feet. It is normally sealed at the consignor’s factory and transported unopened until it reached its destination.
8.Drum	a cylindrical container for liquids and powders usually made of metal or plastic, but sometimes wood or strong cardboard.
9.Barrel	a wooden drum. Hoops are used to strengthen barrels. There are various sizes of barrels, and some are known as casks, hogsheads and kegs.
10.Bale	a package of soft goods (usually textiles) wrapped in protective material.
11.Tin	a small metal container which paint, oil and a variety of foodstuffs are packed in.
12.Carboy	a glass container, used for chemicals, protected in a padded or wicker cage.
13.Bundle	miscellaneous goods packed without a container.

II. Make up sentences using the words from the table above

Reading

I. Before reading the text fill in the first two columns of the kwl Chart.

II. Read the text using the dictionary. Pay attention to the words in bold. After reading the text fill in the third column of the kwl Chart. Kwl Chart

Know	Want	Learnt

Forms of materials

Here for consideration are: packing materials, consumable materials, process materials, maintenance materials, tools and patterns.

The term “packing materials” is self-explanatory; it denotes materials, used for protection and compact packaging to facilitate transit to a destination. In general they comprise strong paper binding or cartons to take standard quantities of an article, wooden cases and stuffing such as wood-wool, greaseproof paper, nails or binding wire, string, hessian, plastic or paper bags. In the main these materials are common over a range of similar products and the amount consigned within a package may vary according to the amount of the order and the method of transport. From a costing point of view the ratio of packing materials to a unit of a product may be haphazard and therefore such costs are classified as indirect materials.

Some packaging, however, may be special or peculiar to a particular product and thus the costs can be measured and identified. Examples will include bottles and plastic containers, tins, product labels and individual cartons for each unit of the product, often specially printed and forming a display medium as part of the process of marketing. These costs are classified as direct materials.

Consumable materials are used to destruction as a general aid in manufacture but do not appear in the finished product. They are by their very nature indirect materials and include:

• Machining oil, used in some engineering machine operations as a cooling agent when a fine finish is required.

• Suds-cooling agent, a form of soap fluid used similarly but when the fine finish is not required.

• Rags and brushes for cleaning.

• Emery paper and powder for improved finishes.

• Chemical cleaning agents.

• Some paints and chemicals.

Process materials. Production materials may sometimes be subjected to processes which change the form, qualities or appearance, such processes needing special agents, liquids or solids, to bring this about. Electroplating needs anodes from which the appropriate finish is transferred to the article in a chemical bath. A process for hardening a metal may call for it to be heated to high temperatures whilst surrounded by carbon granules, and heat treatment of metals may require sudden cooling by immersion, whilst white-hot, in a bath of cold oil. These materials are not necessarily used to destruction at each operation and are therefore classified as indirect materials.

Maintenance materials are used as an aid to production but a stage further removed from the product itself in that they are used in the repair and maintenance of the plant or equipment employed to convert production materials into the finished product. These materials are vital to production and provide the means of ensuring that the plant is kept in good order to guarantee continuity of production, and waiting due to breakdowns is kept to a minimum. Maintenance materials include raw materials in metal created to requirements by the maintenance staff, or ready-made spare parts, such as gear, spindles, bushes and bearings, or sub-assemblies such as gear-boxes, electric motors or headstocks. It is part of the task of the maintenance staff to know the stresses and vulnerable parts of a particular plant and to stock various types of materials in advance of requirement, to minimize the time when the plant is not available for use.

Tools. Small tools are standard tools which can be bought ready-made for the purpose required, and which are for common use in the manufacture of more than one article. They include drills, reamers, plugs and general cutting tools for lathes, milling machines, shapers and the like. They are mainly used to ultimate destruction but can last some time, especially with grinding and sharpening, but during their life they can serve and benefit an extensive range of products. Special tools are obtained for one particular job or product because the expenditure can be measured and related to the product which will receive the exclusive benefit from the use of the tool.

Patterns are used in foundry work, where molten metal, usually cast iron, is poured into moulds which are of a temporary nature but made of special foundry sand sufficiently adhesive to remain in the required shape for the pouring operation. The pattern is the outside master-shape of the product, usually made from wood by a skilled worker. The patterns are virtually permanent are made of metal for durability.