Pressure/gravity (P/G) and electronic gravity (EL-G) fillers are widely used across the bottling industry. Understanding the similarities and differences between these machines can help you make the best decision for your business.

The P/G is a fully mechanical filling valve. Using pressure and gravity, it fills bottles to a level amount (+/- 1/16”.) The valve uses a directional fixed shoe (located in the manifold) that closes the flow at a designated angle, allowing the flow rate to be regulated. The P/G can be used for noncarbonated non particulate liquids like liquor, water, sauces, industrial fluids, juice, pharmaceuticals, detergent, and hot fill. It has been used for decades and is a consistent and reliable option.

In contrast the EL-G uses pneumatic electronic components to provide a level fill (+/- 1/16”) and does not have a mechanical shoe. In the EL-G, a bottle presence sensor tells the machine when there is a bottle under a valve. The intelligent system tells the pneumatics/actuators when to open and close and how much. The EL-G can be used for noncarbonated liquids like juices, sauces, small particulate products, dressings, syrups, liquor, pharmaceuticals, hot or cold fill, dairy, and oil.

The EL-G was introduced to address the growing demand for added control in an ever-changing bottling market. Bottlers began to desire the ability to reduce the amount of overflow created by filling a variety of dissimilar bottle sizes; thus, requiring the concept of an adjustable shoe. Overflow can result in the degradation of product quality and increased utility/operational costs due to reprocessing. Because the EL-G has a unique ability to adjust product flow it can fill multiple bottle sizes instead of just one size, it reduces overflow, maintaining product quality while saving time, power, and money.

Another market need that required addressing was the increase in lighter-weight plastic bottles. As more industry leaders reduced the amount of plastic in their bottles, lessening both cost and environmental impact, the need grew for machines that worked well with lightweight bottles. Because the weight of the P/G can affect some plastic bottles, the EL-G incorporates a neck ring that handles bottles by the neck. 

U.S. Bottlers has long been at the forefront of EL-G innovation and introduced the XV valve in 2018 to provide the ultimate control of product flow. It was created to reduce overflow. The air-actuated XV can shut off product flow completely or to a certain number of degrees allowing for customer filling profiles and the ability to fine-tune the flow more than the EL-G alone. The XV allows customers to be more flexible in the types of products they fill by being able to adjust the fill angles. It also generates utility savings by reducing the rate of return. {Note: The XV valves are available aftermarket and can be retrofitted into existing EL-G machines.

So, how should a customer choose the filler that best suits their needs? Both the P/G and EL-G can be fully washed down, work at the same speed, and have similar lifespans. However, the machine that works best for you depends on various factors. There are several questions to ask when choosing between the P/G and EL-G:

• How many bottle sizes will you use? The P/G works well for multiple bottles that are similar in size or volume. The EL-G is a good option for a wider range of bottle sizes.

• Is controlling overflow an important issue for your product? If so, the EL-G may be preferable. Controlling overflow reduces the cost of reprocessing while helping maintain the integrity of the product quality.

• What are your bottles made of, and do they require neck handling? Thin plastic bottles work well with the EL-G’s neck rings. 

• Are there particulates in your product? If you’re working with a product with particulates, such as pulpy juices, consult with our engineers to find the machine that works best for you as it could be the EL-G or another one of our other filling technologies. 

• How much flexibility do you foresee needing in the future? Will you introduce different products or bottle sizes at a later date? The P/G is a good option for consistent products and bottles, whereas the EL-G allows for flexibility if options change.

Answering these questions based on your products and bottles can help you decide whether the P/G or EL-G is the best fit for your business needs.