FAILURE ANALYSIS OF STEEL – PROCEDURE

Posted on: February 23rd, 2018  /  By:  /  Posted in: #QUALiTYViVA, Quality, SteelFailure, Steelprocess  /  Comment: 0

To investigate the failure of the steel, following general procedure to be followed for systematic analysis of failure and corrective action through study of root cause can be taken, so that chances of failure in future can be eliminated by proper design and use of correct specification. For evaluation of the failure, categorized the failed part in two category and they are:
  1. Finished product use in operation(s).
  2. Semi-finished products which required further processing to convert them in final product.
We will see the above two categories in details: Finished product use in operations. E.g. are Shafts, Bearing, Coupling, Gears and Tools and many more. Points to be check for:
  • Life of the part failed.
  • Date of manufacturing.
  • Design data of part and cross verification for any deviation of application as it is design for and suitable for use.
  • Study the physical condition of the failure part where it was in use.
  • See the environment where it is being working, is other that design for.
Semi-finished products which required further processing to convert them in final product. E.g. are Hot Rolled plates, Hot Rolled coils, Cold rolled products and Galvanized products. Points to be check for:
  • Date of manufacturing.
  • Check the condition of the equipment where product passed through for next process.
  • Check the process capability of the equipment, manufacturing process where it is further processed.
  • Check the competency of the working personal who operate the process where part fail.
Categorizations of the failure on the basis of defects origination, i.e. from process of manufacturing and they are: Defects arising from steel making process
  1. Inclusion
  2. Centre line segregation.
  3. Piping
  4. Seams
  5. Non-metallic inclusion.
Defects arising from rolling process
  1. Oxidation
  2. Scale of oxide
Keeping in mind the above detailed categorization, the failure analysis to be carried out on the basis of four methodology and they are
  1. Primary Investigation
  2. Gathering the related data
  3. Evaluation of failed sample
  4. Data study and root cause analysis
For above four types author acronyms first time as PiGEDA hope this will help to remember easily. Pigeda
  1. Primary Investigation:
Whenever there is failure do the primary analyses of failed piece(s) by involving the cross functional team, constituting of the concern members and their observation, suggestion and comments are to be noted. All the observation, suggestion and comments from the member involved are to be recorded for future discussion and analysis. The observation shall be pertaining to the nature of failure and reasons if any.
  1. Gathering the related data:
The data related to part that fail to be gathered / collected from the related process and form route the product/part manufactured, do the statistical analysis and study for any correlation with respect to failure of part.
  1. Evaluation of failed sample:
For the various defects sample to be evaluated because of which product fail. Carry out the various tests in the laboratory and note the details and findings. As per requirement and nature of defects and part where it fail following test can be carried out:
  • Destructive Test
  • Non- destructive Test
  1. Data study and root cause analysis:
Carry out the study of the data which are results of various test carried out and to be studied for any relationship so that root cause for failure can be ascertain.