The Metalock method is used for cold repairs to cast iron/cast steel and non-weldable metals.
This method is based on limitation and locking of cast cracks, as well as reconditioning of damaged casts. A crack in a cast iron component is locked using a key which takes up both tensile and compressive stresses. Screws called METALACE are driven in along the crack in order to take up shear stresses. This is a cold repair process, superior to welding in the case of crack sensitive materials.
The Metalock Process is a repair system based on fundamental engineering principles, an emergency service on offer throughout the marine and industrial world.
Breakages occur generally because of overloading, misuse of equipment, or flaws in the castings. Fractures are inclined to follow certain patterns depending on the type of equipment involved and the environment in which they are used. This repetition provides Metalock engineers with a wealth of information, on the one hand to be absolutely confident in the repair and also to complete the work within the minimum of time. This long experience also provides the engineer with many techniques, and special fixtures and tools to facilitate the repair have been developed over the years.
1 The fracture, after a survey and report has been presented to the customer, is positioned, realigned, and firmly held together by special fixtures and clamps. 2 By the use of special Jigs, groups of holes are drilled across the line of fracture to the tool depth of thecasting. 3 The Metalock Key is a multi-dumbell shaped section of highly ductile alloy, the size and length being selected to suit thetype of fracture. 4 The holes are then joined by the use of pneumatic chisels to conform to the shape of the Metalock Keys. 5 Individual layers of Keys are inserted in the apertures and peened into a metal-to-metal condition, which becomes almost integral with the parent metal. 6 Holes are then drilled along the line of the fracture, then tapped 7, and filled with studs 8, each stud biting into it's predecessor, resulting in a pressure-tight join and restoring a rigidity to the casting. 9 A Metalock stud is an important aspect of the Metalock process, bearing in mind that pressure repairs are often required. 10 The studs are then run down till the heads shear, the remaining rough metal being removed by pneumatic chisels. Finally the whole repair receives treatment from handgrinders 11 prior to it's final coat of paint 12.