Answer to Question #186696 in Mechanical Engineering for Hannah

Question

Explain why it is important to have access to design reference material which is accurate and up to date when working on design proposals. You should make reference to sources of information such as manufacturers’ catalogues, mechanical and physical properties databases and design databases. You must address the following points:

 How can you determine if reference material is accurate?

 What system should a company have in place to ensure that its engineers have

access to reference material which is accurate and wide ranging?

 What are the technical implications if design calculations are flawed because they

are based on incorrect information?

 What are the financial implications for a business if designers use inaccurate

reference material?

Answer 1

It is very essential aspect for the mechanical system to be manufacture. Design is the first step of the final product to be produced. We will consider boiler chimney design as an example for the ease of understanding.

Now a days boilers are used in many industries such as Commercial Laundry Facilities, Textile Manufacturing Facilities, Automotive Manufacturing, Sugar industry, milk industry etc. Chimney is the part of boiler which releases exhaust gases from boiler to outside environment. Before erection of chimney, design with updated material is very much important for the chimney.

Various standards and codes for design of chimneys in India are as below:

1.   IS 6533: Code of practice for design and construction of steel chimney.

2.   IS 2062 Specification for carbon steel plate's fusion welding quality.

3.   ASTM A 240 Specification for Stainless steel sheets / plates.

4.   IS 814: Welding electrode specification.

5.   IS 875: Code of practice for structural safety of loading standard.

6.   ASME Section VIII Div. 1 Code of practice for unfired pressure vessel.

7.   IS 1367/ASTM A193 Fr B7/ASTM A194 Gr2H: Specification for high tensile bolts & nuts.

8.   IS 3757: High strength fabrication grip tools.

9.   IS 2039: Standards for lightening conductors.

10. IS 158: Specification for temperature resisting and for anti- corrosive paint.

11. IS 808: specification for rolled steel sections (Angle, beams, channel)

12. ANSI B 16.5: For steel pipe flanges and flanged fittings

13. ASTM E 165 Specification for DP testing

For chimney there is requirement of Mild steel and stainless steel material. It is also mentioned in reference design booklet that which grade of CS plates and stainless steel we have to use as a material for chimney. So we have to follow these booklets to choose material of the chimneys.

·        How can you determine if reference material is accurate?

For any product to be manufacture, In each country there are special codes and standards are designed. We have to follow these standards to determine the reference material for the material. Also after material determined, to check whether it is of required grade or not, there are certain type of test available. These tests give full properties of the material which we can study and decide for the further procedure.

• What system should a company have in place to ensure that its engineers have access to reference material which is accurate and wide ranging? 

Company should study about the codes and standards for the materials of the product to be manufacture. Also there are catalogues available everywhere from which also we can determine which grade is now a days applied for specific product.

• What are the technical implications if design calculations are flawed because they are based on incorrect information? 

Quality assurance planning is the main key to avoid such problems in the company. If anyhow, design calculations are flawed, then definitely first sample model which we are going to manufacture will become faulty. If we have a strong quality assurance team then the faulty product will be detected in the first stage and according to that, we can consider that our calculations are wrong. The trial and error method also applies in industries sometimes where sample products are first manufactured and then assured for fitting. If it is not fitted then again recalculations did and the same method repeated till accuracy.

• What are the financial implications for a business if designers use inaccurate reference material?

Definitely, financial losses are going to happen if inaccurate material is chosen as material. Sometimes materials to be used are required with properties like high heat resistant, high hardness, etc. to withstand high heat or loading application. In this case, if we use material with soft grade then definitely in working conditions, it is going to fell in less span of time. So this will add cost to maintenance and restructuring.