Plant of the Month

Valvoline's 12 New Lines Hit Top Speeds

Planning and teamwork pay off; twin lines at its Cincinnati plant quickly meet efficiency goals

By R. Bruce Holmgren
Editorial Director

To respond to market preferences for motor oil and like products in 1-quart bottles instead of composite cans. Valvoline Oil Co. Div. of Ashland Oil, Inc., recently installed 12 bottling lines, spreading these among eight of its plants. Two of them are now running in Valvoline's Cincinnati plant. My own close look at them provides an example of what the firm has accomplished in making the switch.

The bottling line achievements of Valvoline's other plants notwithstanding, however, James D. Jones, operations manager at Cincinnati, points with pride to his twin lines. Their filling speeds range from 350 to 375 quarts a minute. Typical products which were running side by side during my visit were Valvoline's 2 Cycle 50:1 multipurpose lubricant and Valvoline Racing SAE 20W-50 motor oil.

These and other products go into high-density polyethylene bottles, with front and back labels put on by the supplier. Bottles are square, have offset necks, easy-pouring features, clear strips with milliliter and ounce gradations alongside each strip, and use tamper-evident closures.

"I'll put these lines up against any lines in the country," Jones told me, noting that in just three months each line reached 80 per cent efficiency - and later passed that mark. He credits this performance to the quality of the machinery and packaging components - and to the quality performance of the plant work force, which he described as highly motivated.

At the same time, he acknowledged the contribution by Joe Graddy, Valvoline's manager of plant engineering, in planning the lines, as well as help and encouragement from Don W. Detjen, vice president of operations. "Our basic concept was to lay out both lines for the most efficient use of our people - such as positioning machinery to let one operator attend two fillers, for example," Graddy told me.

"We also provided space between them, for access and servicing, as well as to provide storage for packaging components," he noted further. In this context, I understand that Valvoline policy is to maintain minimum raw material storage (this includes bottles, caps and case blanks), along the lines of a just-in-time concept.

Central to the successful operation of the fillers, which means nonstop running, is the supply of bottles to each filler, as well as the takeaway, to assure interruption free runs. This begins with reserve capacity at the depalletizers, as these operate at 450 bottles a minute. It also includes five minutes of accumulation between each depalletizer and filler, and three minutes of accumulation between each filler and case packer, which also has reserve capacity, in that it can run 450 bottles a minute. In contrast, filling speed never exceeds 400 a minute, and with typical products noted earlier, is 350 to 375 a minute.

Fit conveyors to total flow
Translating these requirements into day-to-day action centered on a complete conveyor system developed and installed by Production Systems Inc. Controlled by its own Allen-Bradley microprocessor, it uses a network of photo cells and limit switches to control the movement of bottles. This control includes modulating the speeds for smooth flow with a minimum of stop and starts.

Another contributor to smooth flow is a set of gates, under the same control, to divert the flow of bottles from the infeed of the case packer to a two-and-fro alpine type conveyor.

According to Graddy, the rationale (of the operation) at this point is to feed bottles to and take bottles from each filler faster than the filler itself runs. The system which PSI developed and installed to meet this requirement reflects that rationale.

Focusing on one line for convenience of discussion, my walkthrough from start to finish shows just how the flow moves along.

Each line starts with a Can Lines depalletizer. Directed by its own microprocessor, it takes each pallet, containing 2,431 quart bottles, unloads the bottles tier by tier, row by row, operating at speeds up to 450 bottles a minute. Each depalletizer has an operator who monitors its discharge and flow.

Leaving each depalletizer in single file, the bottles travel on an overhead cable conveyor system, another part of the PSI system. Just ahead of each filler, a PSI lowerator, using pairs of sponge rubber fingers, brings each bottle down onto the infeed conveyor to the filler. Bottles first go through a Pace Packaging orienter, to deliver them for filling with necks and leading.

Bottles next move through an O.C.M.E. filler, running at 350 to 375 per minute, depending on the viscosity and filling characteristics of the product being filled. Each filler has its own microprocessor, directing its operation and then transferring the filled bottles to an adjoining Zalkin capper.

After this, bottles go through an Industrial Dynamics inspector on each line, checking for fill height and cap presence and positioning. Next they pass a Pulse Systems laser coder, which date-codes each bottle. From here, the bottles pass a set of gates, part of the conveyor systems, which either directs them into an alpine accumulation conveyor or lets them move through to a Douglas Machine wraparound case packer, directed by its own microprocessor.

Pack, palletize, ship cases
The point of using the alpine type is to maintain the orientation of the bottles, so that when they reach the case packer, that machine can readily line them up in two rows of six, so that the bottle necks are on the outside in each row, to enhance the stacking strength of the cases.

Once packed, all cases move out on an overhead conveyor that carries them to a Litton/Von Gal palletizer, located at the moment in an adjoining storage area but awaiting transfer to a warehouse now being completed. Each load receives a stretch film wrap on an adjoining Lantech wrapper, after which the loads remain briefly in storage before shipment. Normal practice is to gear line runs to orders so that loads go into shipment within 48 hours of the line runs. Not all runs are long, either. "We have funs ranging from 20,000 cases to as few as 2,000 cases," Jones told me.

Both lines are identical, except that one is of right hand and the other of left hand configuration. Pallet loads of incoming empty bottles go onto parallel tracks as the two depalletizers are side by side. This centralizes the handling of loads, just as does the flow of finished cases into a common area - for loading and wrapping.

Jones explained that the two new lines are more sophisticated than the can lines previously in place at Cincinnati. Just the same, the line crews and the support people quickly took a keen interest in the new equipment. In his view, they readily assimilated its operating niceties - which he attributes to their motivation.

He also noted that monthly meetings at the plant keep everyone up to date. "They understand our goals, based on the projections we share with them, and our line efficiency reflects their desire to work with us in meeting these goals," he added.

Since the first installation of the new equipment, the line crews, mechanics and other plant staff people have come up with many suggestions for improvements. Most of these are minor modifications, such as the palletizers and case packers, but they have improvements in the flow of bottles.

For example, one modification corrected a problem at the depalletizer - to avoid having a paddle strike the last bottle in a row. Changing the single-filler, the paddle action and the speed control of the cable chain resolved it. Another modification corrected a problem at the squaring wall, eliminating a risk of breaking a cylinder at that point.

In explaining the worth of an entire series of such modifications, Jim Jones touched a significant packaging management issue: package tolerances vs. machine performance in the context of the total economics of line and plant output. This focuses on hitting a balance between unduly tight packaging specs, making packages more expensive but less likely to jam, vs. less restrictive specs which hold down package costs but result in more problems on the line.

"Our real challenge in this connection is being able to handle inconsistent bottles and inconsistent corrugated, even though these are within spec," he explained. He cited as an example a 1/16-inch bottle dimensional deviation which, when multiplied 13 bottles across, posed the sort of problem which they corrected at the depalletizer.

Incidentally, a basic crew of six operates these two lines. While each depalletizer has its own operator, one operator can attend two fillers While they have on occasion let one operator attend both case packers, on balance, performance has been better with one operator for each packer.

One line driver looks after supplies such as caps and corrugated for both lines. Likewise, one supply and setup man unloads trucks. With a filler running between 350 and 375 a minute, it takes only six to seven minutes to use up an entire pallet load of quart bottles, even less in the context of a depalletizer's maximum rate of 450 bottles a minute.

These Fillers Don't Stop "With a top depalletizing speed of 450 bottles a minute and a five-minute accumulation between depalletizing and filling - and a top rate of 450 a minute to pack cases, with three-minute accumulation between filling and case packing, Valvoline has virtually eliminated any risk of having to stop a filler. The extra speed and both accumulation zones are enough for almost any typical jam or stoppage - even with filling at an impressive 375 a minute" - R.B.H.