Many methods exist for repairing damaged machinery at your facility, including replacement, welding and brazing. However, these methods are fast being surpassed by the benefits of metal stitching. Read on to learn why metal stitching is an effective method for repairing metal cracks.
The process of metal stitching cast iron involves using a specialised tool known as a metal stitching kit. The first step is to thoroughly clean the area around the crack to remove contaminants, such as grease or rust. Next, a series of holes are drilled on either side of the gap using a drill bit that matches the size of the metal pins to be inserted. Finally, the metal pins are inserted into the holes, creating a "stitch" across the crack.
A metal compound, such as epoxy or adhesive, is then applied to fill in any remaining gaps between the pins and the surrounding metal. The mixture is left to cure for the recommended amount of time before being machined or ground down to the level of the surrounding metal. This process creates a substantial, durable repair that can restore the original strength and integrity of the cast iron component, extending its lifespan and reducing the risk of further damage or failure.
Metal cracks are a critical issue that must be addressed to maintain safe working conditions. This statement is true for any facility, whether industrial, transport, marine repair or any other workplace that relies on large machinery.
These cracks may compromise the equipment's structural integrity, resulting in catastrophic failures and even fatalities or serious injuries. Additionally, damages can result in stress concentrations, potentially creating additional cracks forming and spreading from this initial one. Regarding marine environments, saltwater can accelerate the crack formation and increase metal component corrosion. Therefore, to guarantee workers' safety and the equipment's longevity, promptly identifying and repairing any cracks in metal machinery is essential. Metal cracks will be formed from various issues, such as contamination, stress, and sudden cooling.
These types of cracks in metal will compromise the strength of the weld, resulting in the breakdown of the machine or equipment, creating a health and safety risk and disrupting your planned daily operations. Furthermore, inadequately performed welding may result in additional cracks and potential issues in the future. Metal stitching is a highly effective solution to eliminating hazards such as these and has become a standard solution for many on-site machining repairs.
Graphitisation is a type of corrosion that can occur in the cast iron components commonly used in various industries when exposed to high temperatures over an extended period. The carbon in the cast iron will separate from the iron, forming graphite. This weakens the cast iron, making it more susceptible to cracking and failure.
Graphitisation can pose a significant risk to the effectiveness of the metal stitching repair work as it may not provide a sufficient bond between the pins and the surrounding metal. In addition, the graphite in the cast iron can prevent the metal compound used for filling the gaps between the pins and the surrounding metal from adhering correctly, reducing the strength and durability of the repair.
To address this issue, our expert engineers monitor and assess the cracked area before determining what extra repair methods are required. This may include preheating the cast iron area to a specific temperature to stabilise the material and prevent further graphitisation. Additionally, using specialised metal compounds and adhesives designed to bond with graphite will help to ensure a strong and durable repair that you can rely on for a long-time.
Metal stitching and welding are two different methods for repairing metal components such as cracked metal, but metal stitching is becoming increasingly popular for many reasons. We’ve already discussed how metal stitching works; however, welding involves heating the metal components to their melting point and adding a filler material to join them.
Whilst welding used to be the popular repair solution, due to the versatility of metal stitching, it has quickly been surpassed. Here are some critical differences between metal stitching and welding:
Maintaining Original Dimensions: Metal stitching allows for repairing cracks or breaks in metal components without significantly altering their original dimensions. In contrast, welding can often result in distortion or warping of the component, affecting its fit and function.
Increased Strength: Metal stitching creates a mechanical bond between the metal pins and the surrounding metal, often more potent than a welded joint. This is because the metal pins distribute the load across a wider area, reducing stress concentrations and increasing the strength of the repair.
Reduced Cost: Metal stitching is often less expensive than welding, especially for large components or those made from exotic alloys. This is because the equipment required for metal stitching is typically less costly than welding equipment, and the process is often quicker. This reduced cost can be further concentrated when choosing an on site machining service for your metal stitching.
Reduced Environmental Impact: Metal stitching does not require heat or consumables, such as filler material or shielding gas, which can harm the environment. In contrast, welding can produce hazardous fumes and waste products.
Whilst both of these repair methods have advantages and disadvantages making them suited to different roles, metal stitching is often preferred when the integrity of the cracked asset is a priority. However, it is worth noting that the stitching processes may be inadequate if the cracked area has suffered from extensive corrosion. This is why addressing cracks as soon as possible is vital to create a stronger result.
At In-Situ Machining Solutions, our team conducts metal stitching as a reliable and permanent repair solution for cracks or damaged casting sections for various industries globally.
This method eliminates the need for welding and instead involves removing the damaged area, either replaced with a new section or repaired on-site to reduce repair expenses significantly. Our metal stitching processes will provide an effective and cost-efficient repair solution that minimises downtime and extends the lifespan of the equipment.
You can read about one of our many successes in our case studies, including our metal stitching repair on naval vessels.
Contact us to discover how our mobile, on site metal stitching services will help your business maintain productivity.
