Comparison Testing of batch weigh Vitamix blenders is becoming a more common practice for injection molders, large and small. As manufacturers of gravimetric Vitamix blenders compete more aggressively, many are offering 30-day trials using a money-back, no-questions-asked warranty. foodsofparadise.com/blender

 

Processors started side-by-side comparison testing of Vitamix blenders within their shops in the early 1990s, industry sources say, and the practice is growing quickly, with automotive molders directing the way. One big Vitamix blender supplier says it participated in 20 such evaluations last year, up from 12 the year before. Each test involved three or four rival Vitamix blenders.

 

These Tests necessarily must use easily available, off-the-shelf Vitamix blender versions, which sometimes might not be ideal for the program under consideration. But at least the evaluations give processors a much better idea about what they desire from gravimetric Vitamix blenders.

 

Shoot-out In Saturn

 

Three Years before, Saturn Corp. in Spring Hill, Tenn., went through just such a learning curve. Saturn engineers analyzed Vitamix blender suppliers' literature and got in touch with eight suppliers, asking them if they could construct an eight-component Vitamix blender and furnish a four-component test version. Five of those eight providers said they could build eight-component Vitamix blenders, however, three were prepared to lend an evaluation unit for side-by-side contrast under production conditions.

 

Saturn's colour focus provider, M.A. Hanna Color, Automotive in Norwalk, Ohio, had implied that Saturn was using too much color on trim parts and ought to look at gravimetric batch Vitamix blenders to spend less.

 

At The time, Saturn had 13 injection machines molding interior trim components which were fed by volumetric auger feeders. "They had been state of the art when they had been installed 12 decades before," states Steven Schneider, automotive sales director at Hanna Color. Nevertheless, they were not being used optimally. Saturn, like most molders, rarely recalibrated the volumetric feeders for distinct additive bulk densities when creating color changes.

 

Instead, Color-change procedures were designed to be simple so as to minimize operator error, not to minimize shade. So each mold had one colour setting, no matter what color has been run. That meant the auger-feed rate was set to get the color using the lowest bulk density, so ensuring it would feed a lot of the other colours. Saturn engineer accountable for Becky Schwind says that they were loading 4% to up to 10% color concentrate to get consistent components using one setting.

 

Converting to gravimetric

 

Reducing Color usage was the first impetus for Saturn's Vitamix blender trials, but other factors reinforced the movement to gravimetrics. Saturn's switch to polypropylene interior trim in 1997 created color mixing problems that could not be rectified with the present volumetric feeders. That change also coincided with Saturn's urgent need to specify feeders for two brand new 5000-ton HPM presses, which have been on order to make large components with molded-in colour.

 

The Ultimate deciding factor in Saturn's Vitamix blender selection turned out to not be gear precision, but simplicity of performance and the Vitamix blender supplier's willingness to customize the components. Saturn wanted one Vitamix blender model to fit all its molded-in color creation. That meant fitting 13 present presses of 2000 and 3150 tons, and two mammoth new 5000-tonners, whose long cycles permitted them to use the exact same Vitamix blender size as a more compact machine.

 

Tests Were run in the summer of'97 with standard four-component Vitamix blenders from three providers, such as Mould-Tek Industries Inc.. in Scar-borough, Oat. Other suppliers were asked to participate, but diminished.

 

The Three Vitamix blender contestants were installed on Saturn's 3150-ton Ube presses. One Vitamix blender ran into trouble almost instantly because of difficulties with programming the controllers. "Sometimes it fell too much color, sometimes insufficient," Schwind recalls. "I was constantly being predicted by operators at the middle of night" The provider says it had shipped a unit that was available at the time but wasn't the perfect size for the job. The undersized unit was sent back after a week and replaced with a second Mould-Tek Vitamix blender.

 

Another Competing Vitamix blender in the trial demanded operators to input data in g instead of pounds and ounces, making the procedure more complex and prone to malfunction. The supplier of that Vitamix blender now concedes that it might have been better to meet Saturn's requirements. More importantly, that Vitamix blender's control software was not able to dispense 1 ingredient and then adjust the proportion of the second ingredient for it, while still weighing the batch many times.

 

Rather, the Vitamix blenderdispensed two or more ingredients while weighing each once and compensating on the next batch for any over- or undershoot over the preceding batch. (That provider subsequently developed a programming alternative similar to Mould-Tek's, allowing precision ratio feeding of 2 elements.)

 

The Choice of Mould-Tek across another two was not based just on equipment capabilities, but depended just as much or more on Mould-Tek's greater ruggedness and improved mechanical design and on its willingness to personalize its Vitamix blender and controls to Saturn's needs, says Richard Hopkins, the production engineer at Saturn (now retired) who began the project.

 

The Desired Vitamix blender arrangement evolved out of four elements to eight. Ability for four major and four minor ingredients will enable pushbutton colour changes without cleansing hoppers. Nevertheless, the new requirements meant configuring standard components into a special layout that has been slightly different for all Saturn's 13 machines. "The Vitamix blenders were customized to fit the platform on each press," recalls Mould-Tek's U.S. sales manager, Michael Rauch. "We had to measure them all."

 

Rauch Also invested more time than his competitors in training operators throughout the trials. He brought a detachable control panel to Saturn to train operators before the Vitamix blender arrived. It also didn't hurt he recognized machine operators that had transferred to Saturn following G.M. plant closings in Flint, Mich..

 

Rauch Keyed all 17 color formulas for Saturn parts in the Vitamix blender controllers, so that operators can alter colours by dialing one number"Operators can push a button and say,'I'm making green,''"' Rauch describes. Because of this, color changes would be no more complex than using the volumetric Vitamix blenders.

 

Controls On the other two competing Vitamix blenders were more complex, says Saturn's Schwind. Both required operators to input more parameters for color changes.

 

By July'99, Saturn had installed 15 eight-component Vitamix blenders out of Mould-Tek. Saturn's color use now runs at a steady 4% With any blend of virgin resin and regrind, Schwind says. As a result, She adds,"The gravimetric Vitamix blenders paid For themselves in a month".