Advances in technology have their counter effects too good or bad. Increasing automation leads to arduous demands from an engineering component and the cost of downtime is mind boggling. Particularly for core sector industry like power, cement, sugar, paper, mining, petrochemicals etc. the consequences of wear of part or breakage directly effect the bottom line. Since the investment in this sector is phenomenal the prolongment of machine availability or reduced downtime is critical for the maintenance Engineers. This is because the value of the output per hour in these instances is an enormous as is the toll with every hour of breakdown. An hour of downtime in some industries may cost lacs of rupees. The OEM's of late have been designing components with a average life before failure. This enables the user to plan the replacement of the same before that period. However, by accepting the ways of OEM's the user can do little with his profitability and productivity. To relay on spare parts or resort to cannibalism proves very costly to the industry. Heavy inventory cost and the machine cost due to cannibalism cuts down on profits.

However, clever manager do not rely on these techniques but actively endeavor to use his engineering skills to either prolong the life of the component or resort to maintenance and repair welding. Maintenance welding is unlike production welding wherein the parameters and conditions are all known. For example the base materials are known, required equipment is provided for, parameters are controlled from tests because repetitive jobs have to be carried out. The prototypes developed before commencing main line production are subjected to all sort of destructive and non-destructive tests to confirm required properties in the welds. However, in maintenance welding the Engineer come across a variety of unpredictable factors, limitations and doubts. The consumables should possess special features to overcome handicaps like welding temperature, warping, cracking, bond strength, weldability and solidification rate. Maintenance welding may come across applications wherein the part is poor designed or else may involve improvement in design by strengthening, reinforcing etc. as also fatigued component which have been overworked in capacity to satisfy the production needs. Identifying these difficulties special coatings have been developed for stick electrodes and gas rods to aid the maintenance welders. Special additives are developed to provide better weldability to result into proper orientation of weld constituents/grain refinement. Some electrodes have a low melting core wire and the alloys added through the flux. This results in a circumferential are where are heat is not concentrated on the base metal. In fact most of the heat is utilized in melting the alloys in the flux thereby a minimal energy goes into the base material. The base metallurgy is thus not affected much.