Bob Beecham | posted 12:42 PM, March 22, 2021

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Thread is a very efficient mechanical device, very suitable for connecting pipes. Depending on the material, they can safely transport a variety of fluids and gases, while also being able to withstand extreme environments and high pressures.

However, the threads are prone to wear. One reason may be expansion and contraction, which is the cycle that occurs when the pipeline freezes and thaws. The threads may wear out due to pressure changes or vibrations. Any of these conditions can lead to leakage. In water pipes, this can mean flood losses of up to thousands of dollars. Leaks in gas pipelines can cause fatal consequences.

Instead of replacing the entire pipeline, you can use a range of products to seal the threads. Use sealant as a preventive measure or repair to prevent further leakage. In many cases, pipe thread sealants provide a quick and relatively low-cost solution. The following list focuses on the best pipe thread sealants for a variety of applications.

The goal is to prevent leaks, but the way to achieve this can vary greatly. The best pipe thread sealant for one material is sometimes not suitable for another material. In some cases, various products cannot withstand pressure or temperature. The following product characteristics and shopping considerations can help determine which pipe thread sealant to buy.

Pipe thread sealants are roughly divided into three categories: PTFE tape, pipe paint and anaerobic resin.

PTFE is short for polytetrafluoroethylene, which is a synthetic polymer. It is usually called Teflon, but strictly speaking it is a trade name. PTFE tape has high flexibility and is easy to apply to various metal pipe threads. There are many types of air, water and gas pipes. Telfon is generally not recommended for PVC because it will lubricate the threads. This is not a problem for many materials, but it can make the PVC wire too "slip" and cause damage due to over-tightening.

Pipe paint, also known as pipe joint compound, is a thick, brushable paste, usually compared to putty. It is the most versatile pipe thread sealant and is very effective in most cases. Many are called soft curing compounds. They will not harden completely, so they can compensate for a certain degree of movement or pressure changes.

Pipe coatings are generally the professional's choice; since it is effective on various types of copper pipes used for water and plastic pipes used for drainage pipes, you will find it in most plumber's tool kits. However, it is more expensive than PTFE tape, and it is not easy to use, and most of it is a solvent-based formulation.

The anaerobic resin does not require a solvent to cure, but reacts to remove air from the thread. Resins have properties similar to plastics, so they can fill voids well without shrinking or cracking. Even if there is some movement or vibration, they can be sealed well.

However, these sealing resins require the presence of metal ions to cure, so they are generally not suitable for plastic pipe threads. They may also take up to 24 hours to seal properly. The price of anaerobic resin is higher than that of pipeline coating, making it the most expensive option. Generally speaking, resin products are most suitable for professional applications, rather than general-purpose uses around homes and yards.

Note: Few pipe thread sealants are suitable for pure oxygen. Chemical reaction can cause fire or explosion. Any repairs to the oxygen connector should be carried out by suitably qualified professionals.

In short, PTFE and anaerobic resin pipe thread sealants are suitable for metal pipes, while pipe coatings can seal almost any pipe material. However, it is important to check the suitability of the material in detail. Metal pipes can include copper, brass, aluminum, galvanized steel, stainless steel, and iron. Synthetic materials include ABS, Cycolac, polyethylene, PVC, CPVC, and, in rare cases, reinforced glass fibers.

Although some of the best pipe thread sealants are versatile, not all types are suitable for all pipe materials. Failure to check whether the sealant can effectively cooperate with the specific piping material may cause additional leakage, which may lead to further rectification work.

It is very important to ensure that the pipe thread sealant can cope with the current environmental conditions. In most cases, the sealant should be able to withstand extreme temperatures without freezing or cracking.

Teflon tape seems to be a basic product, but it has amazing elasticity. White general-purpose tape can usually withstand temperatures from minus 212 degrees Fahrenheit to 500 degrees Fahrenheit. The yellow tape used for gas has a similar upper limit, but some can withstand low temperatures of minus 450 degrees.

When it comes to heat and cold, pipe coatings and anaerobic resins do not have exactly the same flexibility. Generally speaking, they can withstand temperatures of approximately minus 50 degrees Fahrenheit to 300 degrees Fahrenheit or 400 degrees Fahrenheit. This is sufficient for many applications, although it may limit outdoor use in certain areas.

Most DIYers may never have to worry about high pressure leaks. The pressure of natural gas is between ⅓ to 1/4 pound per square inch (psi). Although the leak looks serious, the household water pressure is unlikely to exceed 80 psi.

However, in commercial installations, the pressure can be much higher, so the best pipe thread sealant that can handle these environments is needed. The molecular structure of gases and liquids leads to the introduction of different pressure limits. For example, pipeline coatings that can withstand 10,000 psi of liquid pressure can only withstand approximately 3,000 psi of gas pressure.

When choosing the right product for the job, it is important to consider all aspects of thread sealant specifications. To make this task easier for you, these preferred products focus on providing the best pipe thread sealant for leaking pipes based on characteristics such as pipe type or purpose.

Gasoila is a non-hardening pipe coating that contains PTFE to help it maintain flexibility. Therefore, in addition to its high viscosity, the sealant is easy to apply with the provided brush even in cold conditions. These characteristics also mean that joints can resist movement and vibration. This sealant is effective for all commonly used pipe materials, including metals and plastics, as well as pipes containing most gases and liquids. It is safe for hydraulic lines and those who transport gasoline and petroleum solvents because they will corrode some pipe thread sealants.

Gasoila thread sealant can withstand liquid pressures up to 10,000 psi and gas pressures up to 3,000 psi. The operating temperature range from minus 100 degrees to 600 degrees Fahrenheit is one of the most common ranges for pipeline coatings. The sealant complies with internationally recognized general safety standards.

Dixon's industrial sealing tape is a low-cost pipe thread sealant that should have a place in every toolbox. It is easy to use, and there is no danger of dripping on delicate surfaces, and there is no need to clean up. This white PTFE tape produces effective seals in various metal pipes that transport water or air. When the screw is loose, it can also be used to reinforce the old thread.

The operating temperature range of this Dixon tape is minus 212 degrees Fahrenheit to 500 degrees Fahrenheit. Although suitable for many household and commercial applications, it is not designed for high pressure or gas. The product is ¾ inches wide and is ideal for most pipe threads. It has a rolling height of nearly 43 feet, which increases its economy.

Oatey's 31230 pipe joint compound is an excellent general purpose pipe thread sealant. The main purpose of the product is to work with water pipes; the product complies with NSF-61, which specifies the standard for municipal water supply products. However, it can also seal leaks in pipes that carry steam, air, corrosive liquids, and many acids. Oatey pipe joint compounds are suitable for iron, steel, copper, PVC, ABS, Cycolac and polypropylene.

This soft curing formula can withstand temperatures of minus 50 to 500 degrees Fahrenheit, as well as gas up to 3,000 psi and pressures of 10,000 psi. It uses an environmentally friendly and non-toxic formula that stands out as a pipe coating (although it can cause skin irritation).

The main challenge of using sealant on PVC threads is that the user must over-tighten the connection, causing cracking or peeling. PTFE tapes are not recommended because they will lubricate the threads and make them too easy to over-tighten. Rectorseal T Plus 2 contains PTFE, but it also contains resin fibers. These provide additional friction and a safe seal without excessive force.

This soft-curing compound is also suitable for most other pipe materials, including metals and plastics. It can seal pipelines that transport water, gas, and fuel at temperatures ranging from minus 40 degrees Fahrenheit to 300 degrees Fahrenheit. The pressure limit for gas is 2,000 psi and the pressure limit for liquid is 10,000 psi. It can also be pressurized immediately after use.

As a general rule, white PTFE tape is used for general purpose, while yellow PTFE tape like Harvey 017065 PTFE sealant is used for gas. This heavy-duty tape complies with the UL Gas Safety List. This Harvey tape is a multifunctional product; in addition to being recommended for natural gas, butane and propane, it is also suitable for water, oil and gasoline.

This yellow tape can seal all metal and most plastic pipes; however, like all PTFE tapes, it is not recommended for PVC. Its thickness also supports activities such as thread repair on bolts or valve fittings. This tape has a working range from minus 450 degrees to as high as 500 degrees Fahrenheit, and its pressure rating is 100 psi.

Pipeline paint is a multifunctional compound, but it is usually packaged in a can of at least 4 ounces. This is too much for most toolboxes. Rectseal 25790 comes with a convenient tube, ready to use.

This soft curing compound is suitable for plastic and metal pipe threads, and is suitable for sealing pipes containing a variety of gases and fluids (including drinking water). When using gas, air or water at pressures up to 100 psi, it can be pressurized immediately after maintenance. The temperature of this product ranges from minus 50 degrees Fahrenheit to 400 degrees Fahrenheit, the maximum pressure of liquid is 12,000 psi, and the maximum pressure of gas is 2,600 psi.

At this point, you have learned about the various technical aspects to keep in mind when choosing a pipe thread sealant. The preferred section lists some of the best pipe thread sealants for a specific task, but if you still have unresolved issues, check out the useful information below.

Pipe coatings usually work best on PVC. Rectorseal 23631 T Plus 2 pipe thread sealant is the top joint compound for this purpose.

Many sealants are designed to be permanent, but most can be removed if needed. However, if the leak persists, pipes or fittings may need to be replaced to solve the problem.

It depends on the product. For example, soft-curing sealants will never dry completely, so they are more able to withstand vibration or pressure changes.

It depends on the type, but you should always start by cleaning the threads. Teflon tape is applied by winding the external thread in a clockwise direction. After winding three or four times, break it off and press it into the groove. Pipe paint is usually brushed on the external threads.

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