“It’s Leaking Again” – Those Dreaded Words
Whether you’re in the water treatment, chlorine, or bottled gases industry, few words cause the same sense of dismay as those three. The natural inclination is to blame the sealant, but in many cases, the sealant is not to blame.
Fluoramics has done a fishbone analysis on the causes of leaks, and we will break down the elements in this eight-part series.
- Low-Cost, Low-Quality Fittings
- Fitting Material Selection
- Cracked Plastic Fittings
- Tape or No Tape, Type of Tape
- Cold Flow
- Repairs & Maintenance
- Gas Attack & Chemicals
- Type of Thread Sealant
Today we will be focusing on part two: Fitting Material Selection
When it comes to preventing leaks in piping systems, selecting the right fitting material is crucial. Different materials have unique properties that affect their compatibility, durability, and performance in various environments. Understanding these differences can help you make informed decisions and ensure a leak-free system.
Corrosion Resistance
Brass: Brass is commonly used in plumbing due to its excellent resistance to corrosion. However, in environments with high chlorine or ammonia levels, brass can corrode, leading to leaks.
Stainless Steel: This material is highly resistant to corrosion and ideal for harsh environments. Stainless steel fittings are less likely to degrade and cause leaks over time.
Galvanized Steel: Although galvanized steel is coated with a protective layer of zinc, it is still prone to rust, especially if the coating is compromised. Rust can lead to leaks and system failures.
Thermal Expansion
Different materials expand and contract at different rates when exposed to temperature changes. This can impact the integrity of the seal.
Plastic Fittings: Materials like PVC have higher thermal expansion rates compared to metals. This can cause the threads to loosen and create leaks if not properly managed.
Metal Fittings: Metals generally have lower thermal expansion rates and maintain a more consistent seal, reducing the likelihood of leaks due to temperature fluctuations.
Mechanical Strength
The mechanical strength of the fitting material affects its ability to withstand pressure and mechanical stresses.
Steel: Offering high mechanical strength, steel fittings are suitable for high-pressure applications, reducing the risk of leaks due to material failure.
Plastic: While more flexible and easier to work with, plastic fittings have a lower mechanical strength, making them more susceptible to cracking and leaks under high pressure.
Dissimilar Connections
When working with dissimilar connections, watch for different screw threads. One example is using National Pipe Tapered (NPT) fittings with National Gas Taper (NGT) fittings. The NGT is a longer screw thread than NPT. The two pieces will assemble together, but the NGT will typically have 3 more threads in the fitting area. If you mount an NPT to an NGT, you may have leaks.
Another example is the mixing of British Standard Pipe (BSP) threads with NPT or other thread types. BSP threads, commonly used in Europe, are similar to NPT in that both are tapered, but have different thread angles and thread counts per inch. This makes them incompatible with NPT fittings. Trying to connect an NPT fitting to a BSP fitting may result in improper engagement of the threads, creating gaps that allow leaks. The threads may seem to fit initially, but in time, the misalignment will compromise the seal, especially under pressure or temperature fluctuations.
Also, when using dissimilar types of plastics, you may run into threads that do not properly align. The first few threads may line up but as you continue to tighten, the threads may not align. This will cause gaps and leaks. The thread sealant will provide bulk fill and help with the leaks but the problem rests with the dissimilar types of plastics and not with the quality of the sealant.
Choosing the right fitting material for pipe threads is an important decision that significantly impacts the likelihood of leaks. By considering factors like corrosion resistance, thermal expansion, and mechanical strength, you can ensure a durable and leak-free piping system. Make informed choices to keep your systems running smoothly and avoid the dreaded words, “It’s leaking again.”
Use Fluoramics Sealants
Assuming you’ve found the source of your leaks, Fluoramics’ sealants are an excellent option to ensure no further leaking.
- LOX-8 Thread Sealant is highly recommended where oxygen or harsh chemicals such as chlorine or powerful oxidizers are present. It is the product of choice in applications where critical safety and resistance to aggressive chemicals are primary requirements. Providing superior performance as a sealant and anti-galling agent, LOX-8 withstands both high extreme temperatures and high pressure.
- Formula-8 seals threads in gas, liquid, and vacuum service. Oxygen-safe and NSF-approved for food processing facilities, Formula-8 is a water-based thread-sealing compound compatible with hydraulic oils and systems, pvc piping, cryogenics, and high temperatures. This sealant works by wetting into and sealing threaded joints when torqued and is engineered to seal over the entire thread length for the life of the joint in liquid, gas, and vacuum service.
If you haven’t found the source of your leaks, stay tuned for the next edition of Don’t Blame the Sealant where we will be discussing Cracked Plastic Fittings.
Shop LOX-8 Thread Sealant now> LOX-8 Thread Sealant
Shop Formula-8 Now> Formula-8
