A filling machine is a piece of packaging machinery that fills products into containers such as bags, pouches, bins, or bottles. The types of filling machines differ depending on the products being filled, which can include liquids, pastes, granules, and powders.

Filling machines can be manual, semi-automatic, or fully automatic. Automatic filling machines can guide, organize, fill, and release bottles in an automatic bottle packaging line, such as a filling, capping, and labeling line.

When choosing a filling machine, you can consider things like:
The type of container you want to fill
The size of the container you want to fill
How many containers you want to fill
How viscous the liquid is
Whether you need a manual, semi-automatic, or fully automatic machine

Whether the machine meets FDA health and consumer protection guidelines

When choosing a filling machine, you can consider things like:
Product characteristics, Container, Production capacity, Filling accuracy, Automation level, Maintenance, Hygiene, Operator skill, Budget, After-sales support, Compliance.
Here are some other things to consider:
Container size, shape, and material
Bottle compatibility
Integration with other machines
Future output
Regulations
Container size, shape, and material
Vacuum-level filling machine: Can fill most rigid plastic or glass bottles with thinner, free-flowing liquids
Volumetric filling system: Likely to be required for jars, flexible bottles, or pouches
Automatic bottle fillers: Might not be the best choice for containers with non-standard lids or caps
Bottle fillers that grip from the side: May not work well with very wide containers
Regulations
Liquid filling machines for the food industry must meet the FDA's health and consumer protection guidelines

Gravity Filling Machine
Gravity fillers are typically used to fill thinner, foamy liquids. Gravity liquid filling machines work by pumping bulk supplies into holding tanks, which are set above valves that are operated pneumatically. Each valve is set for a specific fill time to enable free-flowing liquids such as water and inks to fill containers using gravity.

Piston Filling Machine
Piston fillers are also ideal for many different liquids. Piston fillers allow for accurate and fast fill rates, along with versatility as they can handle many types of products. They’re frequently used to fill highly viscous products such as pastes, sauces, chunky fillings, batters, and icing. Piston fillers are also often used to fill liquid products in pastry bags and other similar containers.

how piston filling machines work
This type of piston filler is best suited for viscous products that are paste, semi paste, or chunky with large particulates. These piston fillers are built to meet food grade standards and can also handle various chemical applications.

Examples
Heavy sauces, salsas, salad dressings, cosmetic creams, heavy shampoo, gels, and conditioners, paste cleaners and waxes, adhesives, heavy oils and lubricants.

Advantages
This lower cost conventional technology is easy to understand for most users. Fast fill rates are achievable with fairly thick products. Warning: this technology is nearly obsolete with the advent of servo positive displacement fillers.


Pump Filling Machine
Pump fillers are also used for many types of products. Their combined versatility and accuracy makes them ideal for filling liquids of low, medium, or high viscosity levels. The pumps used in these machines can include gear pumps, rotor pumps, cavity pumps, and lobe pumps, among others depending on the application. In addition to pump systems, there are many options for valves and fittings.

Molten Filling Machine
Molten fillers are uniquely designed to work with products that require hot-filling before cooling and hardening once filled. The products that molten fillers are most frequently used to fill include candles, petroleum jelly, deodorants, glycerin soaps, and lip balm.

Pressure/gravity Filling Machine
Pressure/gravity fillers are similar to gravity fillers in their operation, but their use of pressure to fill containers makes them more suitable for thicker liquids.

Net weigh Filling Machine
Net weigh fillers are used to help ensure that every container has the same amount of product across the line, which makes them ideal for filling bulk quantities of liquid products or products of high value whose wastage can be costly.

Inline Filling Machine
Inline liquid filling machines fill containers along a single file line across a conveyor system. These machines are designed to fill liquid and semi-liquid products of various viscosities and in many different container shapes and sizes. Small to medium-sized businesses use these models most frequently to maximize filling efficiency.

Rotary Filling Machine
Rotary filling machines can move containers through circular stations, each of which is intended for a different function such as filling, capping, and sealing. Many industries use these machines for a wide range of products.