Dairy Engineering

Module 7. Filling equipment

Lesson 27
FILLING OPERATION: PRINCIPLE AND WORKING OF DIFFERENT TYPES OF BOTTLE FILLERS AND CAPPING MACHINE

27.1 Introduction

After the process system, the filler is the heart of any milk handling line in a dairy plant. Whether it is simple 6-head rotary filler, or a high-speed multilane linear machine with a hepafiltration chamber, the filler is the center of line activity.

The landscape of the filler business has changed dramatically in recent years, as more and more beverages (including single serve milk) are being sold in plastic. Packaging materials and package sizes have changed, and many manufacturers are now offering different lines of equipment for use with more than one kind of packaging. Machines are faster and achieve higher levels of hygiene for longer shelf life and ambient storage.

Companies have included blow molded plastic in their lines of packaging and equipment. Some companies have got linear aseptic filler for HDPE bottles in commercial use for low acid food and beverages. Companies can now commercially fill low acid products into HDPE plastic containers and distribute them without refrigeration.

The latest filling machines have features like 64-valves with 32 pocket star wheels and designed to fill plastic and glass bottles with a maximum diameter of 3.0' (76 mm) at speeds up to 800 bpm. Other models are available for larger containers. Special features include demountable valve flanges, electronic level control system, filler driven in-feed conveyor, automated lubrication system, automated cleaning and sanitizing system, and digital control system with touch screen operator interface.

Modern machines can have multi-lane inline equipment and can fill in both Ultra-Clean and Aseptic processes. The machine can receive product/s from one of many different UHT processors. Because it is multi-lane, it may be used to fill more than one type or flavor of product simultaneously. Production rates will vary, depending on the number of lanes, the size of the container and the viscosity of the product. Fill time is the major limit on cycle time, but the bottles can be filled in multiple stages to shorten the cycle time.

27.2 Vacuum Filling of Bottles

Fig. 27.1 Vacuum filling of bottles

The bottles after bottle washing machine are fed to the bottle filler by conveyor. The bottles are made to feed on to individually by a star wheel on to a Platform. The platform will rise and fall making it to meet the filler valve positioned above. The mouth of the bottle is pushed against the rubber seal of the filling device thus making it air tight. The air in the bottle is removed due to the vacuum which exists in the upper part of the filling vessel, which will also be rotating along with the platform of bottles. Simultaneously, the opening between the rubber seal and filling tube is released by the raise of the bottle against the rubber seal, and milk enters the bottle, due to low pressure existing in bottle. Once the milk has risen to the level of the hole of the filling tube, no more air can be removed from the bottle, and the filling operation is terminated.

This type of filling has the advantages of rapid filling, reduced milk losses. If the mouth of the bottle is damaged, it cannot properly raise the rubber seal, and milk will not be filled in that bottle. This automatically reduces the product loss. The vacuum system also ensures foam free filling.

27.3 Capping Machine

The capping machine is synchronized with the filling machine. The Al foil, which is usually the capping material, has to pass through a plain or embossed on the die and a punch which is reciprocated o the die. The foil is self lubricated which otherwise will not cut the edges smooth. The foil thickness ranges from 0.04 to 0.05µm. The dia is 38mm and one kg Al foil may give about 3000 caps and a roll of foil may weigh 5 or 6 kg. Plain, coloured or lacquered foils are used.

Fig. 27.2 Capping machine
(Source: C.P Ananthakrishnan (1987)