A unique feeding system on Sweet Ripe Drinks' new pressure filler permits 750-bpm speeds with less glass breakage, higher accuracy and 15-minute changeover.
By David Newcorn, Senior Editor
Sweet Ripe Drinks Mississauga Ontario Canada has boosted line speeds to 750 bottles/min by being the first packager to take advantage of a prototype filler design. The 72-valve pressure filler supplied by Fogg Filler Co. (Holland MI) has been hot-filling juices teas and other beverages since its January '97 start-up. It replaced two fillers on one line-40- and 50-head vacuum-assist gravity machines-whose combined output didn't exceed 500 bpm. What makes this filler unique is that unlike most others there are no bottle transfer points onto and off of the filling turret. Instead bottles travel into around and off the turret on a continuous stainless-steel tabletop conveyor chain. Result: higher speeds increased accuracy reduced spillage and less glass breakage according to Ross Wells operations manager at Sweet Ripe. The concept of using a so-called serpentine conveyor to move bottles instead of turret platforms is simple admits Wells but highly functional. "It was one of those things that you looked at and thought Why didn't somebody invent that thing 50 years ago? We looked at this and said this is the way fillers should be built." The new design has proven itself on Sweet Ripe's filling line. "We don't spill anything and bottle handling is impeccable" says Wells. "Particularly on a glass line we don't get glass breakage. It just lets you fill quicker and move the bottles on and off safer." The combination of more efficient bottle handling and pressure filling results in very high speeds. "We've run this thing as fast as 750 [per minute for a 10-oz bottle]" says Wells. "I see no reason that I couldn't challenge it right up to speeds of 1 [per minute]." Larger bottle sizes such as the 48-oz are run at 250 bottles/min. Other significant benefits are greatly reduced maintenance costs a reduction in labor from two filler operators down to one and slashed changeover times from 21/2 hr down to 15 min. Wells estimates the machine paid for itself in only eight months. To match the higher output Sweet Ripe also installed a new in-line metal lug capper from AHP Machine & Tool Co. (Lancaster OH) formerly Anchor Hocking Packaging and now a division of Crown Cork & Seal. The high-speed capper replaced two older cappers on the same line. Wells says Sweet Ripe constitutes the first Canadian application for the high-speed capper. Other equipment on the line remained the same. No deadplates Sweet Ripe uses the filler for its own Everfresh label as well as for contract and private-label accounts. The machine currently fills 10- 16- 40- 48-oz and 1-L glass bottles in a variety of shapes. "Some of the bottles we run are extremely top-heavy" says Wells but the machine handles them without incident. The packaging line starts out as bottles are delivered to the line via a bulk depalletizer. After passing through an automatic rinser bottles convey onto the filler's infeed. An infeed screw spaces the bottles to match the spacing of the filling valves. Bottles then progress around a 180° turn through a starwheel to begin their trip around the filling turret. After filling they progress around another 180° turn through a discharge starwheel. Pretty standard stuff except for one critical difference: The starwheels don't do the actual conveying. Instead bottles are being carried by the continuous serpentine conveyor supplied also by Fogg the entire time. Result: Bottles aren't passing onto and off of a deadplate which can cause empty bottles to rock at the infeed or full ones to spill at the discharge. Wells explains: "Once a bottle is positioned on the conveyor approximately six feet prior to the infeed star it never leaves that conveyor. There are no transfers." So then why does the Fogg machine use starwheels if they're not necessary to convey bottles on and off the filler? Solely to maintain spacing and to keep bottles from falling in case of a stoppage Wells says. "You can run this machine just fine with the discharge star taken off" emphasizes Larry Toth maintenance manager at Sweet Ripe. Advantages over gravity Once bottles are on the turret valves descend and form a seal with the bottles. Air exits through a return line while product is pumped in under pressure. This differs from a gravity filler which relies on gravity to drain product from a filler bowl into the valves. Indeed there is no filler bowl on this unit. Instead a tank that sits on the floor pumps product at 1.5 to 3 psi through a distribution header and then directly to each valve via individual hoses. Toward the end of the fill cycle excess product is pushed out of the container via pressure from incoming product. Product flow is reduced at this point to a trickle to minimize the amount of product that's returned for reprocessing. There are three benefits to this evacuation: First it prevents overfills since the liquid can never exceed the height of the fill valve. Second it prevents underfills due to foaming which can prematurely shut off a gravity-based filler. That's because any foam that floats on the surface is pushed out through the return line. Wells says fill accuracy on this machine is better than ±1%. Third since at the end of the fill a trickle of product continuously cycles into and out of the container fill temperature is constantly maintained-even if the line stops. That's because the reservoir tank is constantly heated unlike the bowls on Sweet Ripe's previous bowl fillers. Those units occasionally required product that had excessively cooled to be scrapped. This continuous flow maintains hot-fill temperatures in stalled bottles for as long as one hour according to Wells. The benefit: "You don't lose any product and you don't lose any time reheating the filler and getting it going" says Wells. Once bottles are filled the valves disengage and bottles exit around the discharge starwheel again on the same serpentine conveyor. Bottles then enter the in-line belt-style capper from AHP Machine &Tool Co. "It's the only thing that can match a high-speed filler like this" says Wells. The capper applies 38-mm metal lug closures to glass bottles at speeds to 750/min. "It's the same concept that's been around a long time except this one is built out of stainless steel and has beefed-up gearboxes" says Wells. He says such cappers are normally built out of aluminum which "would last fine if you're running up to 400 bpm." From a purchasing standpoint the capper was desirable because it was obtained on a lease agreement tied to the number of caps purchased through sister company Crown Cork & Seal Canada represented in the U.S. by Crown Cork & Seal Closures (Fort Wright KY) also formerly known as Anchor Hocking Packaging. "It's a lease based on throughput so we didn't have to put the capital out" says Wells. Finally since closure and capper come from the same company it guarantees a level of accountability inherent in single-source solutions and eliminates finger-pointing among different vendors in the event of a fault. Operator as changeover artist The filler was purchased with fast changeover in mind. "We took our changeovers down from two and a half hours to fifteen minutes with one person" says Wells. "We don't even use a mechanic. The operator does it all." No tools are required. To initiate a change the operator selects a bottle size on the touchscreen display and the machine automatically adjusts parameters such as filling speeds conveyor speeds and pump speeds. Servo drives automaticaly raise or lower the valves for the correct filling height. The operator simply changes parts such as screws and starwheels which constitutes the majority of the 15-minute changeover. The machine also has a clean-in-place system that flushes all the lines with a cleaning solution. The fast changeover has had a noticeable effect on how production is scheduled according to Wells. "It's actually helped us lower our inventories and keep our turns quicker because we don't have to run a full day on one package size. We can switch in the middle of a run." The machine is also able to fill plastic though right now it's used exclusively for glass. "Every one of my customers large and small has inquired about PET replacing glass" says Wells. This machine was purchased for its ability to fill plastic as well as glass. With a retrofit the machine is also capable of aseptic filling of PET which is something Sweet Ripe may look at in the future according to Wells. In the end the filler has simplified life on the packaging line. "A filler is usually such an onerous beast" concludes Wells. "What this piece of equipment does is take a filler and reduce it to being nothing more than a piece of conveyor" in terms of operational headaches. "And my operators are bored stiff. We've gone back and given them more QA responsibilities" says Wells. Wells gives high marks to Fogg for its part in servicing Sweet Ripe through thick and thin. "We can't compliment Fogg enough for the way they've handled this project. If I were going to buy another filler it would take a real hard sell for me to go to anybody else. These guys are excellent they know their stuff and they respond quickly."