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Metal Stitching & Metal Locking Services for Marine and Power Plants

Metal Stitching And Metal Locking Services

Metal Stitching, also known as Cold Metal Repair or Metal Locking, is a means to restore broken cast iron, cast steel, or aluminum without welding or heat.
Instead of melting the metal like welding does, this method uses specially designed metal keys and stitching pins (locks) to pull the cracked edges together and seal the fracture permanently.

It’s a common fix in heavy industries like,

Marine engine blocks and crankcases
Turbine casings and power plants
Covers for pumps, compressors, and generators
Big machines are used in industry

Why Not Just Weld It?

It sounds straightforward to weld on cast parts, but in reality, it’s not:

Heat makes things bend.
The metal gets weaker because the way its parts work changes.
There may be new cracks around the welded area.
Metal stitching doesn’t have any of that because there is no heat.
The casting’s original strength stays the same.

How the locks and keys really work

The magic of metal stitching lies in installing metal keys and stitching pins directly into the crack.

How to do metal stitching step by step

Step 1: Stop the Crack from Spreading

Small holes are drilled at each end of the crack.
This freezes the crack in place.

Step 2: Install Metal Keys (Locks)

Slots are carefully machined along the crack.
Precision metal keys are inserted into the slots.

What the keys do:

Pull both sides of the crack tightly together
Distribute stress across the repaired area
Restore strength equal to — or even stronger than — the original casting

Step 3: Install Stitching Pins

Small holes are drilled which are perpendicular to the crack.
To seal the crack, metal stitching pins were screwed.

What the pins do:

Hold the area in compression
Make the repair pressure-tight (no leaks — oil, gas, or coolant)

Step 4: Finishing

The repaired surface is machine-smooth and flush.
After finishing, you can barely tell the crack existed.

Why Metal Stitching is a Game Changer

Benefit: What it means

No heat involved, no distortion, no internal metal damage
Strong reinforcement: Strength equal to or greater than the original casting
Leak-proof, Perfect for high-pressure applications
Work done on-site. No dismantling, minimal downtime
Saves money: 60–80% cheaper than replacing the component

Where We Typically Use It

Cracked diesel engine blocks
Turbine or pump casings
Compressor housings
Marine engine frames and bedplates
Generator casings

Metal Stitching And Metal Locking Services uses precision tools, keys, and locks to repair cracks in damaged engine blocks without heat, without distortion, and without messing with the metal’s original strength.

Why R A Power Solutions?

We’re not new to this — we’re experts at this.
With 45+ years of experience and thousands of successful repairs globally, R A Power Solutions repairs:

Engine blocks
Turbine and pump casings
Cylinder liners
Compressor housings

For more information , see the metal stitching and metal surgery process, Metal Stitching And Metal Locking Services, crack casting repair, turbine casing crack repair on site, and crack repair and damaged casting rectification. We also provide crankshaft grinding repair services, crankshaft grinding machines, rebabbitting bearings, etc. Contact us at rajshahani@rapowersolutions.com, info@rapowersolutions.com, or call us at +91 9582647131 or +91 9810012383.

Metal Stitching And Metal Locking Services Metal Stitching, also known as Cold Metal Repair or Metal Locking, is a means to restore broken cast iron, cast steel, or aluminum without welding or heat.Instead of melting the metal like welding does, this method uses specially designed metal keys and stitching pins (locks) to pull the cracked … Continue reading “Metal Stitching & Metal Locking Services for Marine and Power Plants “

Crack Repair Using Metal Stitching and Metal Locking | RA Power Solutions

Cracks in cast iron and other metal components can lead to significant operational challenges in the power generation, marine, manufacturing, and heavy engineering industries. Traditional repair methods, like welding, often introduce thermal stress, weakening the material over time. With over 44 years of experience, RA Power Solutions specializes in metal stitching and metal locking, two highly effective cold repair techniques that restore the integrity of cracked components without causing additional damage.

What is Metal Stitching?

Metal stitching is a cold repair method for mending cracks in cast iron, aluminum, and other metals without welding. It involves drilling precise holes along the crack, inserting metal stitching pins, and locking the pieces together to restore the component’s original strength. This technique is ideal for engine blocks, turbine casings, compressors, and other high-stress industrial machinery parts.

What is Metal Locking?

Metal locking is a reinforcement method used alongside metal stitching. Custom-designed locks are inserted into the stitched area to provide additional support, preventing further crack progression and ensuring a long-lasting repair. This method enhances the durability of the repaired component, making it as strong as or even stronger than the original structure.

Why Choose Metal Stitching and Metal Locking?

Compared to traditional welding, metal stitching and locking offer several advantages:

Cold Repair Process: No heat is applied, preventing material distortion, stress buildup, and further cracking.
Onsite Repairs: No need to transport heavy machinery; repairs can be performed at the client’s location, reducing downtime.
Retains Original Strength: Unlike welding, which can weaken cast iron, metal stitching and metal locking maintain or even improve the structural integrity.
Cost-Effective: Eliminates the need for expensive replacements and reduces overall maintenance costs.

Benefits of Metal Stitching and Metal Locking

RA Power Solutions has successfully performed repairs for various industries, including:

Marine Industry: Repairs on ship engine blocks and connecting rods to avoid costly replacements.
Power Plants: Restoration of turbine casings, generators, and compressors to maintain efficiency.
Manufacturing Plants: Fixing cracks in heavy-duty machines and industrial equipment.

RA Power Solutions provides metal stitching and metal locking services in countries across Asia, the Middle East, Europe, Africa, and the Americas, including India, UAE, USA, UK, Saudi Arabia, Germany, Singapore, and Australia. With a strong global presence, the company offers onsite repair solutions for industries like marine, power plants, and heavy engineering, helping clients avoid costly replacements and downtime. Their expertise extends to Malaysia, Indonesia, Qatar, Oman, Kuwait, Bangladesh, Sri Lanka, the Philippines, Vietnam, Nigeria, Brazil, Germany, Singapore, Malaysia, Indonesia, and South Africa, ensuring reliable crack repair services worldwide.

For more information regarding repair cast iron, repair crack cast iron, or cast iron repair, crack repair by metal stitching and metal locking, contact us at rajshahani@rapowersolutions.com or info@rapowersolutions.com, or call us at +91 9582647131 or +91 9810012383.

Cracks in cast iron and other metal components can lead to significant operational challenges in the power generation, marine, manufacturing, and heavy engineering industries. Traditional repair methods, like welding, often introduce thermal stress, weakening the material over time. With over 44 years of experience, RA Power Solutions specializes in metal stitching and metal locking, two … Continue reading “Crack Repair Using Metal Stitching and Metal Locking | RA Power Solutions”

Cast Iron Crack Repair with Metal Stitching & Metal Locking

Experts highly recommend metal stitching and metal locking for repairing cracks in cast iron. Industries around the world use this cold repair technique because it delivers reliable and effective results when restoring cast iron components.

Broken cast iron pieces can also be replaced by a new piece of casting undertaking metal locking. This technology is as old as the introduction of cast iron casting in industry.

**Insertion of Casting Piece in Engine Block**

**Metal Stitching of Jenbacher Engine Block in Process**

Metal keys and metal locks are used to undertake crack repair in cast iron casting.

Metal keys and Metal Locks are used in Metal Stitching/Locking Process

RA Power Solutions Pvt. Ltd. has a team of trained technicians who carry out metal stitching of broken or cracked castings directly onsite. They bring all necessary tools, consumables, and, if needed, a replacement casting to the site. The team repairs the crack onsite and avoids any need to disassemble or transport the equipment.

**Metal Stitching Done in Broken Area of Generator**

Tests and experience show that metal stitching repairs can strengthen cracked castings. The repaired section often becomes even more durable after the process. We execute crack repairs on board the vessel, in power plants all over the world.

Why Choose Cold Repair Over Welding?

Traditional welding uses heat to damage alignment, change grain structure, and weaken cast iron components. Cold repair procedures such as metal stitching and locking maintain the original material integrity. This results in stress-free, distortion-free, and high-strength solutions.

What Is Metal Stitching & Metal Locking?

Metal stitching is a cold bolt-locking process that includes drilling precise holes along a crack and inserting metal “keys” and studs into a dovetailed pattern. These studs bite into one another, tightening the crack and restoring structural rigidity.
Metal locking supports stitched joints with custom-shaped metal inserts, inhibiting additional proliferation and boosting long-term endurance.

We extend metal stitching services all over the world, including countries like Madagascar, Oman, Qatar, Philippines, Bahrain, Srilanka, Bangladesh, Myanmar, Turkey, Nigeria, Greece, Saudi Arabia, UK, Dubai, Singapore, Malta, and Cyprus, etc.

For more information on crack repair by metal stitching, Cast Iron Crack Repair, cast iron stitching, repair cast iron, cast iron metal stitching services, crack repair in cast iron, and repairing cast iron metal lock, contact us at rajshahani@rapowersolutions.com or info@rapowersolutions.com or call us at +91 9582647131, or +91 9810012383.

FAQs:

1. What is metal stitching in cast iron repair?

Metal stitching is a cold repair process used to restore cracked or damaged cast iron components. It involves inserting special metal keys and locking pins across the crack to mechanically join and seal it—without using heat or welding.

2. How is metal locking different from metal stitching?

While both methods are used together, metal locking adds reinforcement by embedding strong metal locks or inserts that cross the crack. These locks increase structural integrity and prevent further crack propagation.

3. Why is metal stitching better than welding for cast iron?

Welding applies heat that can distort the casting and cause new cracks due to thermal stress. In contrast, metal stitching is a cold process, meaning there’s no heat, no distortion, and the original metallurgical properties remain intact.

Experts highly recommend metal stitching and metal locking for repairing cracks in cast iron. Industries around the world use this cold repair technique because it delivers reliable and effective results when restoring cast iron components. Broken cast iron pieces can also be replaced by a new piece of casting undertaking metal locking. This technology is … Continue reading “Cast Iron Crack Repair with Metal Stitching & Metal Locking”