To keep your home comfortable and save energy costs, make sure it is well-insulated and has an efficient heating system. This includes, among other things, installing and maintaining your plumbing system correctly, especially when it comes to copper pipes. Correct soldering of copper pipes is necessary to ensure leak-free connections, regardless of whether hot or cold water lines are involved. We’ll take you step-by-step through the process of successfully soldering copper pipes in this tutorial, covering both hot and cold soldering techniques.
Soldering copper pipes may seem like a difficult task at first, but with the correct equipment and methods, it can be quite simple. Soldering provides strong, long-lasting connections for plumbing repairs and installation, such as leak detection and repair. It is crucial to comprehend the distinctions between hot and cold soldering techniques in order to select the best strategy for your project.
Sweat soldering, or hot soldering, is a technique that involves heating the joint between two copper pipes with a torch. In order to guarantee that the solder flows evenly around the joint, the pipes must be kept clean, and sufficient flux must be applied. For larger diameter pipes and connections where a stronger bond requires higher temperatures, hot soldering is usually utilized.
In contrast, cold soldering eliminates the need for a torch by using solder paste or gel in conjunction with heat-resistant PTFE tape to create a leak-proof seal. This technique works well in places where it is unsafe or impractical to use a torch, like small spaces or areas near flammable objects. For minor installations or repairs, cold soldering can be a practical substitute because of its simplicity and user-friendliness.
Threaded connection – copper fittings under pressing
Throughout operation, it will require constant observation. It will need to be tightened constantly because it cannot withstand high pressure.
Cut the blanks to the appropriate size first. In the end, any insulation that may have been applied is removed. Get rid of the burrs on the end piece.
Finally, the crimp ring and union nut are attached to it. The connection-thread is tightened after the nut and fitting are connected.
Fumed tape is used for sealing if steel-to-copper adapters are utilized. It is screwed into the fitting after being threaded.
These joints are suitable for locations where ongoing inspections are possible.
Features of soldering
It’s best to become familiar with the ins and outs of this process in order to solder copper water and heating pipes correctly.
In order to visually inspect the joints, such a joint is used in locations where the pipes pass through the floor or wall as well as in other areas with restricted access.
The capillary effect is the fundamental component of the brazing process. Over the cross-section of the pipe, an even layer of solder is applied. Special fittings are also used in the process; these are chosen specifically for each pipe work diameter.
Crucial! For open flame soldering, a gap of between 0.01 and 0.0015 cm is recommended.
Use flux and solder as part of the action as well. There are two subspecies within the soldering technique itself:
- high-temperature;
- low-temperature.
Soft, low-temperature soldering. It is employed in the building of gas and liquid transportation pipe mains.
Throughout the process, the operating temperature rises above 110 degrees Celsius. The range covered by this method is 0.7 to 11 cm. Welding is used to join pipes with wall thicknesses more than 0.16 cm and volumes more than 11 cm.
Hard (high-temperature) soldering. Soldering of this type is essentially non-existent in domestic pipelines. Workpieces for networks operating in high-temperature mode are joined using this technique.
- A properly sized element is prepared with the heat insulation removed and burrs removed.
- Docking area and fitting is cleaned from oxide film.
- Dust is removed and flux is applied to the top part.
- The end of the workpiece is inserted into the fitting (the gap remains no more than 0.04 cm).
- The joint is heated with a torch and the joints are soldered with solder.
Solders
For the purpose of creating a sturdy and superior joint, copper pipes are soldered using both hot and cold solder.
It is composed of paste, rods, wire, and powder. It is important to consider both the soldering technique and the operating temperature when making a choice.
L-SN AG5 and L-SN SB5 are the soft types that are most frequently utilized for copper products. Tin variations with a tiny bit of silver and antimony added are very popular.
These products have an operating temperature range of 240 to 260 degrees. They are permitted for use in food industry heating networks and water supply systems.
These types’ percentage composition of tin is indicated by the numbers 40, 50, and 60. At 190, 210, and 235 degrees Celsius, they melt. The melting point at soldering decreases with increasing alloy tin content.
Our focus in this guide on home insulation and heating is keeping your home warm while using less energy. We cover many important topics, including the proper way to solder copper pipes using both hot and cold soldering techniques. Plumbing jobs like leak repairs and fixture installations require the soldering of copper pipes. You’ll learn the correct methods for both hot and cold soldering, guaranteeing safe and leak-free connections, with our simple-to-follow instructions. Gaining confidence and reducing the cost of professional services are two benefits of learning these soldering techniques, regardless of whether you’re a do-it-yourself enthusiast or a homeowner attempting small repairs.
Hard solder
On the aluminum basis, low-melting versions are widely used. It is recommended to utilize the species L-AL SL12 when conducting activities involving copper products on the installation gap.
Products that contain at least 25% silver in their composition fall under this category as well. This material melts between 600 and 800 degrees.
The type of L-AG 40CD is another item to consider. Additionally, 20% of it is silver. The melting point spectrum falls between 600 and 635 degrees Celsius. It occurs when working with other metals in addition to copper workpieces.
When using soft copper and silver alloys, it is recommended to leave an installation gap of 0.02-0.04 cm in order to create the strongest joints possible.
You can consult a qualified craftsman for advice or look up DIN markings for more comprehensive information on how alloys work.
A crucial component when soldering copper pipes with hard solder is flux. Boron compounds make up its major constituents. They are supplemented with fluorine compounds to increase their activity.
Pure borax can be used for copper soldering. It is a universal fluxer for the high-temperature variety.
Fluxes can be found in various forms:
- powdered;
- liquid;
- crystalline.
| Step | Description |
| Clean the Pipes | Start by cleaning the ends of the copper pipes thoroughly to remove any dirt, debris, or oxidation. Use sandpaper or a wire brush for this task. |
| Apply Flux | Apply a thin layer of flux to the cleaned surfaces of the pipes. Flux helps the solder flow smoothly and creates a strong bond. |
| Assemble the Joint | Fit the pipes together in the desired configuration, ensuring they are aligned properly. Use a pipe cutter to achieve clean, straight cuts if necessary. |
| Heat the Joint | Using a propane torch, evenly heat the joint where the pipes meet. Heat the joint until the flux begins to bubble and turn brown. |
| Apply Solder | Once the joint is heated sufficiently, touch the tip of the solder wire to the joint. The solder should melt and flow into the joint by capillary action, creating a secure seal. |
| Cool and Inspect | Allow the soldered joint to cool naturally. Once cooled, inspect the joint for any leaks or defects. If necessary, reheat and apply more solder to achieve a proper seal. |
In order to perform plumbing installations or repairs, a homeowner must be able to solder copper pipes. To ensure a safe and successful outcome, it’s imperative to comprehend the process, regardless of whether you’re working with hot or cold soldering techniques.
The technique of joining metals at room temperature without the use of a heat source that reaches a high temperature is called cold soldering, or cold welding. This technique is especially helpful for minor repairs or in confined areas where using a torch might not be practical. It’s crucial to remember, though, that in order to achieve a solid bond, cold soldering calls for clean surfaces and the right setup.
Conversely, hot soldering depends on the use of heat to melt solder and form a connection between copper pipes. When done correctly, this method, which is frequently employed in larger plumbing projects, offers a strong and long-lasting connection. To prevent damaging the pipes or creating leaks, it is imperative to use a propane torch or a soldering iron with the proper temperature settings.
A successful outcome depends on adequate preparation, regardless of the soldering technique employed. To ensure a strong bond, this involves cleaning the surfaces of the pipes that need to be joined, applying flux to encourage solder flow, and evenly heating the joint. To further reduce mishaps and injuries, it is imperative to follow proper safety procedures, such as donning protective gear and operating in an area with adequate ventilation.
In conclusion, copper pipe soldering is a useful skill that any homeowner can acquire. Knowing the differences between hot and cold soldering techniques and adhering to the correct procedures will help you achieve professional-quality results and preserve the integrity of your plumbing system for years to come, whether you’re taking on a minor repair or a major installation.
