Press Fit Stainless Steel
What are Stainless Steel Press Fit Fittings?
Stainless Steel Press Fit fittings are a modern, reliable, and efficient method for joining stainless steel pipes without the need for heat, solder, threading, or welding. Instead, the joint is formed using a mechanical press tool that compresses the fitting onto the pipe, creating a permanent, leak-tight seal. This is achieved with the help of a specially designed EPDM o-ring, ensuring a secure and durable connection that can withstand high pressures and a wide range of temperatures.
Press Fit technology represents a major advancement in pipe jointing systems, offering several key advantages over other options:
- Faster Installation: Joints are completed in seconds, significantly reducing installation time compared to other methods.
- No Hot Works: As no heat is used, Press Fit eliminates the risks associated with flames, sparks, and combustible materials, making it ideal for occupied or confined spaces.
- Consistency and Reliability: Each press produces a uniform joint with consistent sealing pressure, reducing human error and the risk of leaks.
- Clean & Hygenic: No flux, solder or sealing compound means a cleaner installation, ideal for potable water systems.
How do Stainless Steel Press Fit Fittings Work?
The press fit fittings are designed in such a way that the socket profile deforms in a controlled manner when pressed, which in turn presses the o-ring down, providing a consistent and reliable seal to the pipe. Here's a basic overview of how to press a joint.
- Preperation
- The pipe should be cut square and the end deburred and cleaned to ensure a smooth surface. This prevents damage to the o-ring when inserting the pipe, which could affect the seal integrity.
- Marking
- The cut pipe should be laid next to the fitting, and a mark should be made on the pipe equidistant from the middle of the fitting; this marks the insertion depth, helping to ensure the pipe is fully inserted before the press is made.
- Insertion
- Insert the pipe all the way into the fitting; the o-ring may provide some resistance. Ensure the edge of the pipe reaches the marking. The joint is now ready for pressing.
- Pressing
- Using a press tool with the correct profile jaws, position the jaws around the fitting; it should slot into place.
- Activate the pressing cycle; this will apply high mechanical pressure, deforming the fitting around the pipe in a controlled manner. Simultaneously locking the pipe in place and compressing the O-ring to form a secure seal.
Stainless Steel vs Other Materials
Stainless steel is perfect for long-term installations, offering exceptional reliability and performance in demanding environments compared to materials like copper.
- Corrosion Resistance
- Stainless Steel is exceptionally resistant to corrosion, especially when it comes to aggressive or hard water environments. It is also highly resistant to oxidation.
- Great for long-term resistance to corrosion and chemical degradation.
- Stength
- Although both our Stainless Steel and Copper Press Fit systems are rated to the same temperature and pressure (as per the seal inside), Stainless Steel is more rigid and expands less under thermal load, meaning it can be more suitable for high-temperature systems and is less prone to mechanical damage.
- Durability & Lifespan
- Most Press Fit systems are likely to last over 50 years, even in demanding environments; however, Stainless Steel holds the edge over other materials as it is non-reactive and maintains integrity over decades with minimal maintenance.
- Especially suitable for long-term commercial and industrial installations.
- Hygiene
- Smooth internal surfaces inhibit bacterial growth and biofilm formation. It’s fully compatible with drinking water and maintains water purity without leaching.
- Suitable for use in a food-safe environment, where other materials may not be.
- Thermal Conductivity
- Stainless Steel has lower heat conductivity compared to materials like copper, meaning less heat loss through the pipe wall. This is ideal for efficiency but suboptimal for quick heat transfer.
How to Remove Stainless Steel Press Fit Fittings
When a press fitting is installed, the pressing tool mechanically deforms the fitting’s collar around the pipe, permanently compressing the O-ring and locking the pipe in place. Because of this, the joint cannot be reused or re-pressed; any fitting that’s been pressed must be discarded once removed. To remove a press fit fitting, use a pipe cutter to cut through the pipe a short distance away from the fitting, then remove the entire section, including the fitting, and dispose of it.
There are some important notes to keep in mind when removing and replacing fittings:
- Never attempt to repress or reuse a fitting; it will not seal properly and may fail under pressure, which can be dangerous and costly.
- Check that the system pressure is fully released before cutting into the pipe to prevent pressure discharge and injury.
- Inspect the pipe after removal. If the surface is scored, dented or deformed, it should be cut back further to a section of undamaged pipe before attempting reinstallation.
If you require any further information, our excellent customer service team is here to help so please call us on 01794 835835.
