Comparing Different Types of Pipe Plugs
When it comes to stopping flow in a pipeline, there are several different pipe plug options available to you. Which one you choose will depend on a variety of factors, including the type of substance you’re blocking, how much pressure there is, how you’re accessing the inside of the pipeline, how long you’re blocking the pipeline, and your purpose for stopping flow in the first place.
In this article, we’re discussing which type of pipe plug is best for different applications, so you ensure you have the right one for your next project.
Mechanical vs. Inflatable pipe plugs
The two major pipe plug options to choose from are mechanical and inflatable. There are several advantages and disadvantages to each type:
Mechanical plugs
This type of pipe plug works by inserting it into the line and then mechanically expanding it to create a tight seal. Mechanical plugs are used for blocking and testing pipelines, and they allow you to work on or test specific sections without shutting down the entire system.
Pros – Mechanical plugs don’t need to be inflated, so they do not require inflation equipment or media. Plus, they are ideal for long term pipeline blocking projects, because you don’t have to worry about them slowly deflating over time.
Cons – The largest disadvantage of mechanical plugs is that they are rigid, so they cannot form an effective seal when there are weld beads, corrosion, deposits, an out of round pipe shape, or other imperfections. Additionally, these types of pipe plugs aren’t able to fit through small hot tap holes.
Inflatable plugs
Inflatable plugs are made from flexible material, allowing them to be inserted into a pipeline and then filled with gas or liquid. Once filled, they fit snugly within the interior of the pipe, creating an effective seal.
Pros – The advantages of inflatable plugs include the ability to fit through small openings and conform to almost any shape, they are easy to store and transport, and they are generally more cost effective than mechanical plugs.
Cons – The biggest drawback for inflatable plugs is they may not be used as the only means of protection of people downstream and they require a separate inflation pressure source. Also, most standard inflatable plugs have a lower pressure rating than a mechanical plug.
Different types of mechanical and inflatable plugs
Within the categories of mechanical and inflatable plugs, there are several different options available. Here are some of the most common types:
Mechanical blocking plugs – Blocking plugs are used for stopping flow for maintenance in sanitary, storm sewer, and similar systems.
Mechanical bypass plugs – Bypass plugs are used for the installation and repair of residential or commercial piping systems. They are required when a repair or test is needed, but you are unable to shut down the entire system.
Inflatable test ball plugs – These inflatable plugs are used for blocking the flow during maintenance in sanitary or sewer systems, and can also be used as back plugs for sewer air tests. They don’t have a bypass and are designed specifically for sealing a pipe.
Inflatable bypass plugs – These bypass plugs are used for testing and monitoring pipe systems. Some inflatable bypass plugs are designed to handle high back pressure in applications such as water mains, force mains, and industrial lines.
T-Handle mechanical plugs – T-Handle plugs are a type of rigid plug that are ideal for long term blocking and bypassing operations.
If you have any questions about choosing the right pipe plug for your application, please reach out to the Petersen team today!
