On site Metal stitching and metal locking is a precise mechanical method of making permanent repairs to broken casting and machine parts.
No heat is used, thus no stresses are introduced and no post-repair machining is necessary to correct misalignment and warpage. Since there is no heat, metal locking and metal stitching repairs can be made in restricted areas where flames or welding arc is prohibited Repairs are done on location in the plant, without the necessity of major dis-assembly.
Maintaining production and reducing down time of broken equipment presents many new challenges. Solutions are arrived at after a careful analysis and then applying our experience to make a proper, dependable repair by on site Metal Locking Process. The quality and craftsmanship thus achieved have earned for us the recommendation and endorsement of equipment manufacturers, insurance underwriters and inspection services.
Main Area of Application of On site Metal Locking and On site Metal Stitching:
On site Repair of damaged Crankcase, Turbine Casing, Castings by Metal Stitching and Metal Locking Process and metal stitching process.
On site Repair of Cracked, Broken Casting of Pillars, Hammers, Heavy Machine Tools, Forging Presses.
On site Metal Stitching or Metal Locking of Cement, Fertilizer, Steel, Sugar Plants, Machinery which get damaged due to accident.
In situ Metal Stitching and metal locking of Engine Block of Cast Iron
Procedure of On site Metal Stitching and Metal Locking
Drilling fixture is attached of right angles to the crack. A hole pattern is drilled and this is repeated at intervals from ¾ to 1 ¼ inches apart.
Metal between each drilled hole is removed by ripping it away with pneumatic tools to form a slot. The stock thus removed is narrower than the drilled hole, thus forming a serrated opening.
Preformed locks of high tensile alloy are inserted in to the slot. These locks are peened into the slots, one on top of the other, to a depth limited by the casting thickness and determined by the strength required.
After the locks are installed, holes are drilled, tapped and threaded, fasteners are applied. These are spotted along the entire length of the crack, overlapping one another. Their purpose, in part, is to fill the fracture with new metal and provide a pressure seal.
Entire repair area is peened, flush and finish ground.
In case of the broken casting, the new casting is manufactured in accordance to the metallurgy of the parent casting. The assistance of pattern maker is taken to manufacture the casting strictly as per the profile of the damaged area.
The necessary care is taken even for aesthetic look of the new casting which fully gets merged with the old one.
I) Crack Repair in Engine Block, Entablature or Repair of Broken Casting by metal locking and metal stiching. II) Checking of main journal housings and correction by metal stitching and metal locking process. III) Repair of damaged threads by metal stitching/metal locking and use of helicoil.