Automatic Pigging in Chocolate Production

This case study illustrates how a pigging system from HPS helps a well-known chocolate manufacturer to quickly and efficiently remove product, speed up changeovers and minimise downtime.

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  • HPS designed, supplied and commissioned an automatic pigging system for a well-known manufacturer of chocolate-based confectionery products
  • The system enables the confectionery manufacturer to quickly and efficiently remove residual product from a full-scale test area of production
  • The HPS pigging solution removes sufficient product to enable standard production to continue with minimum downtime
  • Cross-contamination is prevented and significantly less time needed for cleaning and changeovers
  • Product removal rates are high enough to eliminate any need for oil, butter or other flush
  • Overall time required for testing is reduced, increasing line efficiency
  • Test product is also recovered rather than wasted so if necessary can be reused
  • The test area can be quickly transferred back to production when required

If you’re not sure what pigging means, here’s an overview.

About the Client

The HPS client is one of the world’s best-known nutrition, health and wellness companies. It has a rich history going back over 150 years, and today has a wide range of businesses, a large number of brands and a diverse range of products.

HPS worked with a research and development team within the company, at a facility producing some of the company’s most popular chocolate, biscuit and snack products. The team develops new technologies and innovative products, while also providing technical help and assistance to other areas of the business.

Project Background

To test new products, the company set up a test bed line in part of its main production area. This allows the research and development team to conduct trials and research in a full-scale factory environment.

It’s important that testing is as efficient as possible. It must keep to a schedule to avoid any disruption to manufacture. When the research and development team has finished using the test facility, any remaining test product in the pipes must be removed quickly and effectively. When the pipelines are clean, normal manufacturing operations can continue as normal.

Why the Company Chose HPS as their Pigging Systems Provider

HPS has a strong reputation as the world’s leading hygienic and sanitary pigging systems specialist. Having worked with a wide variety of companies that manufacture chocolate and confectionery, the HPS team has an in-depth understanding of the special requirements of this type of product. In addition, HPS has implemented product recovery and pigging solutions at some of the company’s other facilities. These include factories in the UK, US and Brazil.

The Solution

HPS designed, supplied and commissioned a four-inch single-pig automatic tank-select product recovery solution for use with chocolate and chocolate-based products. This was deployed on the new test bed line in the main production area, which allows the research and development team to test product in a full-scale system.

The pigging system operates between two batch storage tanks and five drop-off destinations. The HPS solution includes all equipment required to launch, receive and return the pig, including the pneumatics and air sets to propel the pig using filtered air. It also includes a bi-directional fully-detectable food-grade pig along with pig detectors to enable safe, reliable and accurate PLC control. The solution includes several types of valves.  Where required these are jacketed and have visual sensor position indicators.

HPS also provided full drawings and electrical connection diagrams. Once the equipment was in place, an HPS engineer tested and commissioned it. HPS also delivered full training to relevant staff.

The Results

The HPS pigging solution reduces overall time required for testing, increasing line efficiency. It quickly and effectively removes sufficient product to enable standard production to continue with minimum downtime, while preventing cross-contamination. Typically, HPS systems recover up to 99.5% of residual product.

Although water flushes are not used with chocolate, sometimes manufacturers use products such as butter oil to flush the lines. Because pigging removes nearly all the test product, in this case there’s no need to use flushes. In addition, there’s significantly less time needed for cleaning and changeovers from test to main production. The test product is recovered rather than wasted, so if necessary the company can reuse it.

By using pigging, the research and development team can quickly transfer the test area back to production when required.