Niaz presentation1

FORGING DEFECTS AND IT's REMEDIES

1. FORGING DEFECTS & IT’s REMEDIES UNDER THE GUIDANCE OF VINEET CHAK BY – NIAJ AHMED ROLL No - 44201

2. FORGING Forging is defined as a metal working process in which the useful shape of work piece is obtained in solid state by compressive forces applied through the use of dies and tools.

3. DEFECTS Something that detracts from perfection . MAN MACHINE MATERIAL METHOD

4. CONTENTS 1 UNDERFILLING 2 MISMATCH 3 SCALE PITS 4 COLD SHUTS 5 SURFACE CRACKING 6 OVERLAPPING 7 DENT

5. UNDERFILLING FISH BONE DIAGRAM FOR ROOT CAUSE OF UNDERFILLING Reason :- Remedies :- Less stock volume. Poor die design a. Not proper selection of parting line. Proper billet temp. b. Improper dimension of flash width Proper die design like parting line, flash width & thickness. & thickness no of preform die. c. Insufficient no of impression. Pre heated the die. Less billet temperature. Proper load calculation. Low preheating of die. Correct lubricant Insufficient load. Improper lubrication. Presence of gas in deeper cavity.

6. MISMATCH MISMATCH CALCULATION

7. SCALE PITS FISH BONE DIAGRAM FOR ROOT CAUSE OF SCALE PITS PITTING Pitting looks like a hole in the forging surface. Reason :- Presence of scale in the dies. Presence of scale on the billet. Remedies :- Billet & dies must be free form scale.

8. COLD SHUTS Cold Shut include small cracks at corners. REMEDIES:- The fillet radius of the die should be increased to remove these defects Chilling should me minimized. Reason:- Due to improper design of forging dies and it maybe due to sharp corner, excessive chilling in forge product.

9. SURFACE CRACKING Remedies :- Properly heat the billet. Reject defected raw material. Proper equipment selection. Reason :- Non uniform distribution of billet temp. Input material defect. Not proper deformation rate.

10. OVERLAPPING Reason :- If the fillet radius is too small, due to poor die design. Dies are not preheated. Not sufficient preform impression. Remedies :- Fillet radius is as large as possible. Accurate billet temperature. Dies must be pre heated. More preform impression.

11. DENT Reason :- It is caused due to careless handling of jobs during or after forging. Improper positioning of stock on the die. Remedies :- Proper placement of stock in dies and proper handling of hot forging.

12. CONCLUSION A failure in a forging may have been caused by material selection, deficiency in design, improper processing , fabrication or deterioration resulting from service condition. During forgings operations, several types of defects may be developed. Among them laps, folds, seams, cracks tears and forged in all pipe is solidification shrinkage defect carried through Ingot stage and detected as a small round cavity located near the centre of an end surface.

13. THANKYOU HAVE A GOOD DAY.