Drilling

Peening

Pre heating

Post heating

To decrease the mechanical property

To increase labour cost

To increase idle time

To increase mechanical operating efficiency

Procedure Qualification Record (PQR)

Welder Procedure Specification (WPS)

Welding Procedure Qualification (WPS)

Welder Performance Qualification (WPQ)

To get brittleness

To reduce mechanical operating efficiency

Instead of buying new repairing of old parts

To increase labour cost

Abrasion

Erosion

Impact load

Friction