metal stitching engine block Archives

What Is Metal Stitching and Metal Locking? A Trusted Cold Repair Technique: RA Power Solutions

When a metal component cracks—especially in large equipment like engine blocks, compressors, or turbines—repair options can be costly, time-consuming, and risky if not done correctly. One highly effective method that avoids heat, preserves alignment, and restores structural integrity is metal stitching, also known as metal locking.

Understanding Metal Stitching

Metal stitching is a cold mechanical repair process used to fix cracks or breaks in cast metals such as cast iron, aluminum, steel, and bronze. Unlike welding, which uses high heat, metal stitching relies on precision-drilled holes, specially designed stitching pins a nd locks to seal and reinforce the damaged area.
This technique is ideal for industrial applications where heat could distort components or where disassembly isn’t feasible.

Damaged Crankshaft before metal stitching

How the Process Works

Here’s a simplified breakdown of how metal stitching is done:

Crack Detection: Identify and inspect the full extent of the crack.
Drilling Pattern: A series of holes is drilled along and across the crack.
Slot Cutting: A slot is formed to fit stitching locks or keys.
Installing Locks: Metal locks are inserted into the slots to mechanically bind both sides of the crack.
Threaded Studs: In some cases, overlapping threaded studs are used to seal the crack.
Sealing & Finishing: The surface is peened and machined smooth to match the surrounding area.

Why RA PowerSolutions?

At RA PowerSolutions, we specialize in on site metal stitching and metal locking for all types of cast components. There is no need for dismantling or transporting the part.
With decades of experience and hundreds of successful global repairs. We help industries reduce downtime, avoid expensive replacements, and restore strength and performance efficiently.

Our services include:

Metal stitching of engine blocks, compressors, pumps, etc.
On site machining and grinding
Repair of crack-prone components like turbine casings and gearbox housings
ISO-certified technicians and portable tools

If you’re facing a critical breakdown or seeking long-term solutions for metal cracks, RA PowerSolutions is ready to assist with expert, onsite support. Contact us today to learn more or schedule an inspection.

For more details on the Metal Stitching and Metal Locking , Crack Repair by Metal Stitchng email us at info@rapowersolutions.com. Call at +91-9582647131,+91 9810012383.

FAQs:

1. What is metal locking?

Metal locking crack repair process – Metal-lock or metal stitching is a method of repairing fractures to castings, onsite without the use of heat. It involves sinking Metal-lock keys, perpendicular to a fracture. The fracture is then sealed and held rigid by Metal-lace studs

2. How is metal stitching better than welding?

Metal stitching does not use heat, so there’s no distortion or weakening of the material. It preserves the original shape and alignment of the part and is ideal for cast iron, which is prone to cracking when welded.

3. Can metal stitching be done on-site?

Yes, RA Power Solutions specializes in on site metal stitching, allowing us to repair damaged equipment without dismantling or transporting it—saving time, cost, and downtime.

Overhauling of Main Engine Repair | Repair of Engine Metal Stitching of Damaged Block

RA Power Solutions received an emergency call from a Steel Company based in Indonesia regarding damage of their Engine SULZER 6RND68.

On arrival of our team of engineers, it was observed that lower engine block of SULZER 6RND68 was damaged badly. Hence it required disassembly of complete engine, overhauling and repair of engine block by metal stitching & metal locking.

Following is the brief of job description executed:

Inspection and overhaul of the cylinder covers including the fuel and starting valves located in the covers. The cylinder covers cooling spaces were also inspected, cleaned and fitted back with new O-rings.
Dismount, Inspect and overhaul the exhaust valves, renewed the seals and grinding the valve spindles.
The cylinder liners were cleaned, calibrated and honed in order to restore the liners running surfaces and remove ovality. This ensured that the piston rings perform better and this will lead to a better overall cylinder condition, compared to if honing had not been done. The cylinder liners cooling spaces were also inspected, cleaned and fitted back with new o-rings.
Replacement of thrust block pads and correction of end play.
Metal locking of damaged Engine block by our technicians.

Special Keys & Locks Used in Metal Stitching Process

Repair of Engine Block by Metal Stitching is in Process

Inspected and adjusted the chain drive.
Retightened the stay-bolts, holding down bolts end chocks.
Took bearing clearances with a telescopic feeler gauge and checked bearing edges by wire gauges.
Crankshaft alignment measurement was taken with dial gauge (autolog method)
Conclusion: The engine was tested on full load for 72 hours & all the parameter were recorded. The engine is performing satisfactorily.

Repair & Overhauling of Engine is in Process

Inspection of Engine Spare Parts is in Process

For more details regarding Metal Stitching of Damaged Block, overhauling of engine, repair of engine metal stitching of damaged block, crankshaft grinding, and engine block repair please email us at rajshahani@rapowersolutions.com, or info@rapowersolutions.com, or call us at +91 9582647131 or +91 9810012383.

Metal Stitching and Metal Locking of Engine Blocks – RA Power Solutions

Engine blocks, casting and most of the parts are manufactured of common material like cast iron. Cracks developed in cast iron parts are most difficult to undertake repair by welding process as it needs pre-heating of the cast iron prior to the welding. In certain cases it can cost additional stresses resulting to the damage of casting.

It is proven that metal stitching and metal locking have the advantage of repairing cracks in cast iron casting due to the cold process using different profiles and materials of stitching pins and locks without applying any heat, as in the case of welding.

RA Power Solutions Pvt. Ltd. undertakes metal stitching and metal locking of casting and has successfully repaired various major components of a high-capacity diesel engine.

Application includes repair of Engine Block, Cylinder Head, Generators. Turbo Chargers, Turbine Casing, Gear Box Housing, Pump Casings, Compressor Crank Cases, Forgings Hammer, Lathe / Press/ Milling/Boaring etc .M/c. Other all Casting equipment etc.

In the last 45 years, more than 10,000 jobs of crack repair have been successfully executed.

Stitching Pin Used in Metal Stitching Process

Metal Stitching Done in Broken Area of Generator

RA Power Solutions is proud to say that we have a dedicated team of specialists who specialize in metal lock and metal stitching repairs. We promise good performance on all of our jobs. We have shown to be cost-effective and can deploy our team of professionals and consumables on short notice. We have recently expanded these services to Dubai, Greece, Maldives, Malaysia, Singapore, Madagascar, Nigeria, South America, UAE, Germany, Monaco, Qatar, Sri Lanka, Bangladesh, Italy, Spain, Czech Republic, UK, Nepal, Philippines, Jordan, Libya, Kuwait, Egypt, Morocco, Yemen, Bahrain, Tunisia, Sudan, Oman, Algeria, Saudi Arabia, Iraq, and others.

For more details regarding crack repair by metal stitching, engine block repair, cold metal lock stitching, and cast iron by metal lock & metal stitching, please email us at rajshahani@rapowersolutions.com, or info@rapowersolutions.com, or call us at +91 9582647131 or +91 9810012383.