tailieunhanh - Engineering Drawing for Manufacture phần 2

Các tiêu chuẩn cao nhất "là những người quốc tế kể từ khi họ cho phép các công ty hoạt động trong thị trường toàn cầu. Các tổ chức chịu trách nhiệm cho các quy tắc quốc tế là Tổ chức tiêu chuẩn quốc tế (ISO). Có hàng trăm tiêu chuẩn ISO trên bản vẽ kỹ thuật và lý do là bản vẽ là rất phức tạp và chuyển giao chính xác của thông tin phải được đảm bảo. | Principles of engineering drawing 11 the only one that provides a full specification which allows contracts to be issued and has the support of the law in the servant-master sense. To put it in the words of a BSI drawing manual National and international legal requirements that may place constraints on designs and designers should be identified. . These may not only be concerned with the aspect of health and safety of material but also the avoidance of danger to persons and property when material is being used stored transported or tested Parker 1991 . Representation and specification In Section it was stated that engineering drawing was the equivalent of a language. A language has to have a set of rules and regulations for it to operate correctly. The same is true of engineering drawing. In the English language there are two basic rules. The first is the word order that gives information on subject and object. The second is spelling which gives information on the words themselves in terms of the spelling . the nouns verbs etc. Considering the word order the phrase the cat sat on the mat is very different from the phrase the mat sat on the cat . All that has happened is that the words cat and mat have been swapped. Previously the phrase described a perfectly feasible situation whereas it now describes an impossible situation. Thus the word order gives information on which is the subject and which is the object. The second set of rules concern sections and cutting planes auxiliary projections views tolerances surface finish assembly Typical standards IS0128-1982 130128-34 2001 ISO-44 2001 130128-50 2001 ISO7573 1983. Typical standards IS015768 2OO1 2001 ISO128-22 1999 ISO406 1987 ISO1101 1983 IS01302 2001. Figure Representation visualization and specification 12 Engineering drawing for manufacture spelling and thus the phrase the cat sat on the mat is very different from the bat sat on the mat and yet this difference is the result of only