A Filling Machine for the Personal Care Products Industry – Positive Displacement Capable

Personal care products include both liquid soaps and shampoos as well as cosmetic products including lotions, creams and pastes. Because liquid soaps and shampoos are relatively thin viscosity, they are capable of being filled on more than one type of filling machine. An Overflow Filling Machine can handle a limited range viscosity of liquid soaps, shampoos and lighter conditioners. This machine is only mentioned here as an exception because it really cannot address the typical range of viscosities for personal care products manufacturers; an Overflow Filling Machine will simply not function at all for heavier cosmetics or even heavy shampoos and conditioners. Even liquid soap filling on an overflow filler has limited application for small producers. As the viscosity of the soaps increase, the number of nozzles needed to maintain the desired output on an overflow filler will correspondingly increase and thereby increase the capital cost up until the point that it is now at par with the cost per output of a smaller piston filling machine.

Most cosmetic products require a positive displacement type filling machine that can volumetrically fill relatively viscous products. Because these viscous products flow quite slowly, they must be forced through a fluid path under some pressure to deliver them into the container. This is also true where the shape and opening of a container will not lend itself to anything other method. Positive displacement volumetric fillers such as the piston filler and servo pump filling machine are designed for this purpose and are best suited to the Personal Care Products Industry.

Piston Filling Machines have long been the machine of choice in the cosmetic industry because of its relatively high output for difficult (viscous) products, its mid level capital cost and relatively ease of operator understanding and maintenance cost of this conventional technology. This type of filling machine is also very accurate in providing a volumetric fill size to within +/- 1% of required fill volume. With typical output of 10 containers per minute per nozzle, a fairly small footprint machine can handle large production volumes. To increase output of cosmetic products on a piston filling machine, they are commonly configured with jacketed product hoppers to increase the flow characteristics of the products through the machine as well as maintain resultant process temperatures during manufacturing.

The disadvantage of piston filling machines is that they invariably require disassembly of the entire fluid path for thorough cleaning between batches. Changeover of fill sizes on typical mechanical piston fillers does take a little bit of adjustment and time. Although, good machine design with tool-less disassembly and changeover is very helpful in this regard, one cannot escape the changeover time associated with multi nozzle systems on conventional piston fillers. If a producer has a relatively small range of bottle sizes, the changeover time is generally not a problem. There are higher level technology piston fillers using digitally encoded servo drives and ball screw drives to memorize the speed and stroke length of a piston filler but these machines add a level of maintenance complexity and cost to a machine that is already proven to be a workhorse in its mechanical form. Although Inline Filling Systems has designs and experience for these higher tech forms of a piston filler, keeping a piston filler design as simple as possible is the best strategy for the owner.

One economic trend in the cosmetic industry is the fact that the number of products a producer must offer is increasing while the batch sizes of these products is decreasing. This puts an additional burden on the cosmetic producer with more frequent changeovers and cleanups. While a Piston Filling Machine is excellent for handling these types of products, its weakness is that it does not clean up quickly and requires adjustment in the setup process to dial in the correct fill sizes after each changeover. Thus, a piston filler can be at a disadvantage to some cosmetic companies with many Stock Keeping Units (SKU’s) in their product line. Whereas servo drive or ball screw system on a piston filler can decrease changeover time, cleanup time remains the biggest disadvantage.

A Servo Pump Filling Machine is almost ideally suited to the cosmetic industry because it not only handles a wide range of product viscosities but also cleans up and changes over very quickly. The Servo Pump Filling Machine is an extremely flexible filling machine in a class of its own which can fill almost any cosmetic product you can imagine. Because it uses positive displacement pumps dedicated to each nozzle it can handle an extremely wide range of viscosities within the range of the particular pump specified on the machine.

The major advantage of this filling machine is its ease of cleaning and this makes it very convenient for producers that have many SKU’s of products that must be produced in a single day. A computer controlled pump dedicated to each filling nozzle allows for total programmatic control of all filling parameters with unlimited fill sizes, high volumetric accuracy and the ability to deliver almost any thick or thin sanitary product into almost any container. These machines have built in cleaning cycles that allow the entire machine to be self cleaning between changeovers depending on the level of automation the buyer wishes to invest in. This type of filling machine overcomes all of the shortcomings of a piston filler and is an extremely efficient production tool for the personal products industry.

However, the Servo Pump Filling Machine’s capital cost is not low. Each servo controlled pump/nozzle combination typically costs over $10,000 per nozzle. However, this machine pays for itself with tremendous productivity compared to other systems (like the piston filling machine above) where cleanup and changeover time is a mere fraction of the time in the productive day. In fact, filling machine operating parameters can be permanently stored in memory for instantaneous recall during the setup procedure. As mentioned above this superior filling technology makes it possible for the producer to fill many unrelated product batches in the same day and be very responsive to his or her customers.

The choice of positive displacement filling machine would depend on what relative advantage is more important: speed and versatility versus cost. The least expensive filling machine that can package these liquid products is the overflow filling machine. It is also the slowest producer but with great flexibility. A piston filler is a fast producer at higher cost but with some disadvantage in changeover time, fill size range and cleanup time. The servo pump filler can fill any size container at fast rates with fast cleanups but at high capital cost.