The heat exchanger is leaking; seeking advice on ways to fix the leak

With different materials, electrochemical corrosion will definitely occur. If the two materials are not very different from each other, the corrosion should not be severe. And anyway, it’s already blocked; just block it again if there’s a leak

As long as the welding is good and the medium is not highly corrosive, there should be no problems.

Corrosion won’t occur; it’s just a matter of whether your white steel is easy to weld or not.

This post was last edited by gn_1984 on 2015-11-29 at 19:20. Introduction to the special adhesive for plasticized composite leak sealing: This special adhesive is a high-tech repair material that features safety, efficiency, non-toxicity, and fast performance; it is an ideal emergency repair product for the chemical industry. XX Company, in collaboration with relevant domestic research institutions, has developed this product based on the actual conditions in chemical manufacturing facilities. It is designed for use in areas prone to fire and explosion, environments with corrosive substances, as well as in high- and low-temperature conditions, helping to reduce safety incidents and save labor and materials. Our company’s special leak-sealing adhesive is tailored specifically for chemical enterprises, combining multiple advantageous properties to eliminate concerns related to maintenance work. The product specifications are as follows: Operating temperature: up to 400°C at high temperatures, and 100°C at low temperatures. Working media: acidic substances, alkaline substances, oils, methanol, benzene, and other flammable and explosive hazardous materials. Operating pressure: below 4.0 MPa, with good insulation properties. Application range: Repair of pipes, tanks, and tower equipment made of various hard materials, as well as maintenance work such as leak sealing. It can also be widely used in the construction industry, shipbuilding industry, and automotive industry; it is an essential product for you. Compared to traditional methods, it has the following advantages: 1. No welding is required; operations can be carried out manually, which reduces the need for a large amount of labor, saves time and resources, and eliminates safety hazards associated with welding or other types of operations ； Simple, safe, and fast. 2. The operation method is simple and easy to learn; no training is required, and it can be operated by one person alone, saving labor costs. 3. Repairing certain special materials (such as alloy materials) does not require the hassle of acquiring special welding materials and equipment, **reducing maintenance costs. 4. The shelf life of this product is 5 years; any unused clay should be stored sealed to avoid further waste. Operation steps: 1. First, clean the oil stains and dirt from the leaking area or the part that needs repair to keep the working surface clean. (For some leaking pipes or tanks, pressure relief or sealing measures should be taken first; for materials such as gasoline and benzene, appropriate procedures must be followed.) If possible, use a file or other tools to roughen the surface to be repaired, thereby improving adhesion. Then, keep the working surface moist by spraying water as appropriate. 2. Take an appropriate amount of each type of clay in a 1:1 ratio, roll each type of clay into strips (a scale can be used if available; the more precise the ratio, the better the result). Then twist the two strips together to form a spiral shape. Keep your fingers moist – use clean water in summer and warm water in winter to wet your fingers. Keep rolling and mixing until the clays take on one uniform color. At this point, the clays should be warm, sticky, and shiny (if not, it’s a fake product); they are now ready for use. 3. Before applying the putty for repair, keep the area to be repaired moist; if it is dry, spray an appropriate amount of hot water on it. Then press the putty into the cracks or leakage points, adjusting its thickness as needed depending on the requirements, but make sure it isn’t too thin. Keep your fingers moist while pressing the surface firmly to level and smooth it out, and finally wipe it clean with a clean, wet cloth to complete the task. Precautions: 1. The mixing and kneading of the clay must be completed within 15 minutes from the start of application; if too much time passes, it will lose its stickiness and become unusable for construction ； 2. After construction, it takes 2 hours for the material to cure in summer, 4 hours to harden, and 8 hours before it can be used. If there is no sunlight, the curing time needs to be increased accordingly. During winter construction, if the clay-like material is not soft enough, it can be heated using a hair dryer or hot water. In areas that are not flammable or explosive, moderate heating can be applied after the work is completed to accelerate curing (but direct heating with fire should be avoided; a hair dryer is sufficient). In winter, without heating, it takes 4 hours for the material to cure, 8 hours to harden, and 18 hours before it can be used. 3. If operation is to be carried out under pressure, the company’s specialized clamps can be used first to seal the area, followed by applying adhesive; once the adhesive has cured, the clamps can be removed. These specialized clamps can be reused. If there are no professional maintenance personnel on site, contact our company, which can send professionals to provide guidance or resolve the issue on-site ； Please contact us promptly in case of special operating conditions. Product specifications: Our company’s products are available in the following specifications: A50g + B50g – packaged at 100g; A100g + B100g – packaged at 200g; A250g + B250g – packaged at 500g. We welcome you to use our products; your satisfaction is our constant goal.

Please do not leave the company name or contact information.

1 The same material should be used; welding different types of steel can lead to quality issues. 2 Plugging leaks should generally be entrusted to specialized companies, as it is not something that ordinary enterprises can handle properly.

Our experience shows that blocking is possible, but special care must be taken to avoid any adverse effects on the surrounding heat exchange tubes during the blocking process. Since the mixing of the media in the tube side and shell side of our heat exchangers can lead to corrosion at the welds between the heat exchange tubes and the tube sheet, posing a potential risk, we generally seal off 6–8 adjacent heat exchange tubes as well. Of course, there is another very important issue, which is determining the cause of the leakage in the heat exchange tubes: whether it is due to welding defects between the heat exchange tubes and the tube sheet ； It’s still a defect in the heat exchange tube itself ； It’s still due to scaling in the tube bank and high temperatures ； It is still the vibration of the heat exchange tubes that causes the welds between the heat exchange tubes and the tube sheet to separate ； Or the vibration of the heat exchange tubes is blocked by the baffle plates, and so on. Generally, by removing the leaking heat exchange tubes, it is possible to identify the root cause of the leakage, allowing for more targeted corrective actions. This helps to prevent repeated blockages of the tubes, which could otherwise affect production.

It is also necessary to consider the impact of fins on heat transfer; the number of fin roots should preferably not exceed the available area of the heat exchanger, in order to meet the process requirements. Otherwise, too many blockages will occur and the process requirements won’t be met, so it needs to be replaced directly.