Here are some ideas for pouring out liquid materials.
Home and Hobby: pour using a spout on a jug, place the liquid in a baker's piping bag, or into a ziptop bag and then cut the corner.
Small-Scale Manufacturing: Gravity fillers (for thin liquids): manually open and close a valve while the liquid runs into the container.
Medium-Scale Manufacturing: Piston fillers(for thin or thick liquids): piston fillers automatically measure the same volume into each container and can either be manual (hand pulled) or connected to a compressor to be activated by a foot pump.
Large-Scale Manufacturing: several connected and automated piston fillers in an in-line conveyor system, usually including a scale for a filled weight check and other process steps such as bottle sealing.