With the variety of utility pigging types available, how do you know which combination of pigging methods is right for your facility? B&W Energy Services is here to help you explore your options and break down the most common kinds of utility pigging in the industry.
Utility Pigging
What is Utility Pigging?
Utility pigging is used for a variety of purposes, including cleaning, dewatering and sealing piping systems. A pig travels through the interior of the piping system to remove debris and contaminants that obstruct or limit flow. Depending on its intended purpose, a utility pig may have brushes or sensors to help clean the piping system effectively.
Utility pigging consists of several subcategories, including batch, sealing, mandrel, solid cast, spherical, foam, gel and ice pigging. B&W Energy Services may not offer each of these services, but we’re happy to discuss your pigging needs with you.
Batch Pigging
What is Batch Pigging?
Batch pigging creates an effective barrier between various products that travel through the same piping system. It separates substances into different batches, preventing cross-contamination and improving the flow of products within a piping system.
Pros of Batch Pigging
One advantage of batch pigging is that several cleaning and displacement procedures can occur at once, maximizing efficiency. Transporting multiple products through the same piping system is more economical than creating piping systems for each product. Batch pigs are also versatile, as they can be unidirectional with scraper cup attachments or bidirectional with attached discs.
Cons of Batch Pigging
Most batch pigging is run onstream and has to occur at the same velocity as the product stream. If this doesn’t happen, the batch pig could repeatedly start and stop while traveling through the piping system, making this particular application less effective.
Recommended Use Cases for Batch Pigging
Besides separating various products within the same piping system, batch pigging is also useful for displacement and filling lines with water. Other types of pigging that are good for batching include solid cast, spherical, foam and gel pigging.
Sealing Pigging
What is Sealing Pigging?
Sealing pigging uses specialized pigs made from rubber or polyurethane in order to prevent leaks. This method also stops moisture and air from entering piping systems.
Pros of Sealing Pigging
Both rubber pigs and polyurethane pigs are highly durable yet flexible. This combination allows them to make excellent sealants for your piping systems while adjusting to changing diameters and bends throughout a piping system.
Cons of Sealing Pigging
High humidity and exposure to excessive sunlight and ultraviolet light can damage polyurethane. Storing your polyurethane pigs properly and shielding them from the elements is essential to preserving your pigs.
Recommended Use Cases for Sealing Pigging
Sealing pigging is highly effective if liquids need to be flushed out of a piping system and kept out while preventing air from getting in. Due to solid cast pigs’ compact and robust design, solid cast pigging serves as a good substitute for sealing pigging if necessary.
Mandrel Pigging
What is Mandrel Pigging?
As its name suggests, mandrel pigging utilizes a central mandrel that keeps a pig sturdy while it cleans or inspects piping systems. Mandrel pigs, also known as solid-body pigs or criss-cross pigs, are designed with an easily customizable metal body to remove debris and maintain the piping systems’ integrity as they clean.
Pros of Mandrel Pigging
Mandrel pigs can be customized with replaceable discs, cups, scraper brushes or gauging plates to perform various tasks. Their steel body creates a long-lasting pig, and the interchangeable components create multiple pigs in one! As a result, mandrel pigging is a particularly cost-effective pigging method.
Cons of Mandrel Pigging
Due to mandrel pigs’ varying attachments, there is a chance that a pig may get stuck in a piping system, requiring plenty of time, money and effort to remove it. However, this is a possible outcome with many pigging types.
Recommended Use Cases for Mandrel Pigging
Mandrel pigs with discs are ideal for debris removal, while cups may be added for extra sealing power. By choosing mandrel pigging for your facility, you choose a pigging method that’s extremely reliable with lots of room for personalization.
Solid Cast Pigging
What is Solid Cast Pigging?
Solid cast pigging uses polyurethane or steel pigs without any moving components to clean and inspect piping systems. A solid cast pig’s compact design lends itself well to removing debris and other contaminants from piping systems.
Pros of Solid Cast Pigging
If you need a robust pigging method for your project, solid cast pigging is a viable option. The simple, durable design of solid cast pigs allows them to travel through piping systems efficiently while providing an effective clean. You can also add discs, brushes or other attachments to accomplish specific tasks and reuse the same kind of pig for various purposes.
Cons of Solid Cast Pigging
Although having sturdy pigs is advantageous, steel’s high density may become a problem if a steel pig gets stuck in a piping system. The use of polyurethane pigs poses a similar risk.
Recommended Use Cases for Solid Cast Pigging
Solid cast pigging may be used for several routine pipeline pigging operations, including cleaning, batching, gauging and displacement. It may also serve as an alternative to sealing pigging.
Spherical Pigging
What is Spherical Pigging?
Spherical pigging utilizes either solid spheres or inflatable spheres made of polyurethane or neoprene to perform pipeline pigging operations. The inflatable spheres are filled with water or glycol so they retain their shape when exposed to pressure changes within a piping system.
Pros of Spherical Pigging
The shape of spherical pigs allows them to travel quickly through piping systems to perform operations efficiently.
Cons of Spherical Pigging
Spherical pigs often require additional design considerations, resulting in an added cost. They also usually become undersized as they travel and don’t clean piping systems’ interiors as effectively as other types of pigs.
Recommended Use Cases for Spherical Pigging
Spherical pigging’s best use cases include batching and liquid removal. Foam pigging is an effective alternative for batching purposes and has an added cleaning advantage over spherical pigging.
Foam Pigging
What is Foam Pigging?
Foam pigging uses polyurethane foam pigs to remove debris and liquids from piping systems. Deemed the most basic kind of pig, foam pigs come in various densities to match the contamination levels within your piping system.
Pros of Foam Pigging
Foam pigs are lightweight and flexible yet highly durable. They easily mold to changing diameters, bends and turns within piping systems and more. Foam pigs are also versatile, offering different configurations and designs depending on your project’s requirements.
Cons of Foam Pigging
If you’re looking for a more aggressive cleaning solution, foam pigging is not the best choice. The polyurethane used for many foam pigs offers a less abrasive clean than more dense materials like steel.
Recommended Use Cases for Foam Pigging
Foam pigging performs batching and light cleaning operations well. Spherical pigging can be performed instead of foam pigging for both purposes, but foam pigging has more cleaning power than spherical pigging.
Gel Pigging
What is Gel Pigging?
Gel pigging uses pigs made of high-viscosity gels and rigid polymers to remove debris from piping systems or retrieve stuck pigs from piping systems. They may also be used alongside more traditional pigs to improve efficiency and prevent damage to the primary pig.
Pros of Gel Pigging
Gel pigs may be pumped through any piping system that accepts liquids, and they’re known for being able to pig the “unpiggable.” Internal valves, sharp bends and other obstructions within piping systems are no match for a gel pig. They also don’t wear out during service like traditional pigs, and they don’t require a launcher or catcher.
Cons of Gel Pigging
Although gel pigs don’t wear out easily, they are susceptible to dilution and gas cutting. Due to this, it’s important to make sure that a traditional pig follows behind a gel pig when a piping system displaces with gas.
Recommended Use Cases for Gel Pigging
Gel pigging is often used in tandem with more traditional pigging types to optimize cleaning, batching and dewatering tasks. When a gel pig is sent through a piping system with another pig, the gel pigs can improve overall performance without sticking a pig.
Ice Pigging
What is Ice Pigging?
As its name suggests, ice pigging uses slurry ice rather than a more traditional solid pig to clean the interiors of piping systems.
Pros of Ice Pigging
One of the most notable benefits of ice pigging is that if the slurry becomes blocked while traveling through a piping system, it will eventually melt. A pig made from slurry ice also allows the pig to be more malleable than a traditional pig. This way, it can better adapt to varying pipe sizes and bends in the piping system. Ice pigging also doesn’t require a launcher or catcher to be installed, so this pigging method takes less time to set up.
Cons of Ice Pigging
Ice pigs are less effective than traditional pigs in removing intense corrosion or calcified fats, oils and greases. There is also a smaller chance that an ice pig will discover obstructions since it can’t be tracked and melts if it gets stuck.
Recommended Use Cases for Ice Pigging
Ice pigging is most effective when used on small-bore piping. For piping systems with larger diameters, don’t use ice pigging unless there are various twists and turns that a more solid pig wouldn’t be able to pass.
Different levels of contamination require different pigging applications, and our team collaborates closely with you to create customized solutions for your project.