Scrapers, Moles, Cleaners and Go Devils

pig moving through a pipeWhat Else Can You Call a Pipeline Pig?

While there are many people in the process and utility industries that know exactly what ‘pigging’ is, it’s certainly not a well-known term. In fact, one of the most common questions we’re asked by people outside of the business is what it means. What’s more, the ‘what is pigging’ page on this website gets an extremely high number of reads. This shows a lot of people are interested in finding out what it is and how it works.

Nothing to do with Even-Toed Ungulates

There’s no getting away from it, ‘pigging’ is a perplexing term. It doesn’t describe what our products do, that is, reduce waste, recover product, increase operational efficiency and help towards environmental sustainability. In fact, many people assume we work in agriculture. Others assume that we have something to do with the sport of pig hunting. In reality, we have nothing whatsoever to do with Sus Scrofa Domesticus, the even-toed ungulate most people know as the domestic pig.

There are many other definitions of pigging which also have nothing to do with liquid product recovery systems (or the domestic pig). And this confusion can cause misunderstanding, curiosity or sometimes a bit of amusement.

Other Names for Pipeline Pigspipeline pigs

As well as being a confusing term in itself, not everyone refers to pipeline produce recovery using solid projectiles as pigging. For example, in some parts of the world, the projectiles that travel through pipes to recover liquid (the pipeline pigs) are known as ‘moles’. The same devices are also sometimes referred to as ‘scrapers’ or scraping devices. They’re occasionally referred to as ‘cleaners’, and even ‘go-devils’, which is a hangover from process pigging’s roots in the oil industry.

And to add to the confusion, the word pigging doesn’t translate that well from English to other languages.

So what’s a good term?

Scrapers

There are devices, similar to pigs, specifically designed to remove product from the insides of pipe by literally scraping it off. These are sometimes called scrapers, or scraping pigs. However, the term scrapers isn’t ideal when it’s used to refer to process pigs. Scraping can imply damage or scratching, and in turn potential contamination. In most processes, particularly sanitary or hygienic applications, contamination is unacceptable.

Molesmoles cause damage

The term mole, like pig, is quite endearing (who doesn’t love a cute little mole – unless it’s digging up your prize lawn). But it’s not really descriptive. Maybe more so than calling it a pig, in that a mole is something that disappears down a tunnel and works its way through it. But it still needs some clarifying for those not in the know.

Cleaners

Cleaners is a descriptive term. However, while cleaning the inside of pipes is part of what pigging does, it’s not the sole aim. There are also other methods of cleaning pipelines, such as flushing and CIP, which often go hand-in-hand with the pigging process. So ‘cleaner’ is not a good fit.

Go Devils

Go devil is a general term given to a wide variety of devices, objects and groups. It’s only occasionally applied to process pigging applications. In fact, we’ve only heard it used rarely and it may be specific to one or two companies. But people use it nonetheless.

Go devil is a confusing term because it applies to several different things. For example, a go devil can mean a type of sled, a railway truck, a cultivator, a weight used to set off an explosive, a fishing device and an engine. What’s more, it’s also used by various organisations, clubs and societies as their name.

Product Recovery Devices?

The term “pig” is confusing because it doesn’t describe what the device does. Similarly, there’s confusion between process pigging and pigging systems used in the oil, gas and utility industries. While their origins may have certain things in common, the technologies themselves have diversified significantly.

So what else can you call what are commonly known as process or pipeline pigs? How about product recovery devices? Or product recovery projectiles? Or pipeline liquid recoverers? Then again, the pig itself is no use without the rest of the components that make up a pigging system. So perhaps we should just stick to calling them ‘pigs’?

Ideas, Suggestions and Further Information

If you call ‘pigs’ something different from the terms mentioned in this article, or have any suggestions about more suitable terms that could be used, please email info@hps-pigging.com with your comments.

Alternatively, for further information about pigging systems for process industries, please contact us.