Filling Fast but Not Furiously
Challenged to provide fillers that operate quickly but accurately, suppliers are turning to servomotors to drive key machine functions.
Deadlines in the pharmaceutical industry are tight these days. Companies need to get their products packaged and labeled as quickly as possible, so they can beat their competitors to a clinical trial, product launch, or brand extension. However, they can't afford to sacrifice product quality.
For products to be packaged and labeled quickly, every piece of machinery on a packaging line must work together efficiently to achieve high speeds. Fillers, however, aren't known to be the fastest machines on a line, especially since they almost always operate intermittently, slowing a product down after it exits a continuous-motion machine. In fact, fillers have been the bottleneck on some packaging lines.
Several machinery suppliers are taking steps to improve filling speeds. "To meet or exceed a customer's speed requirements, the entire packaging line must run considerably faster than before," explains Ha Dinh, vice president of engineering for All-Fill Inc. (Exton, PA). "Since the heart of the packaging line is usually the filling equipment, it is expected to run at increased rates, while maintaining an acceptable level of accuracy."
Suppliers have made numerous improvements intended to speed up filling processes, but one of the most notable developments is the increasing use of servomotor technology. According to Bill Arden, marketing manager of Bosch Packaging Technology (Minneapolis), future designs of fillers will make more extensive use of servomotors, motors that receive power from amplifiers to drive loads with linear or rotary motion. "They're easy to reprogram—they beat the heck out of changing or modifying cams."
Because of their simple design, servomotors enable machines to operate much more quickly than before. And, because they can be programmed, their movement can be controlled much more easily than that of the more traditional cams, helping to ensure accuracy at high speeds. Coming full circle, better management of machine motion leads to faster filling speeds, says Bosch's Arden.
|Mateer Burt's Neotron System Series 1800D auger filler can handle up to 400 containers per minute.|
Thanks to servomotors, many filling equipment suppliers have been able to increase machinery speed. Consequently, most of the newest machine introductions utilize servomotors in some manner.
According to Rusty Sparling, director of sales for IWKA PacSystems (Fairfield, NJ), which has added servo drives to its TFS 80 tube filler, "mechanical stroke and cam settings have literally been made obsolete by the extensive use of servo-driven systems. With servo drives, we are able to deliver benefits that include ease of changeover, speed of changeover, and the ability to offer the use of off-the-shelf components to save costs while permitting more flexible solutions."
Norden Packaging (Branchburg, NJ) is using servomotors for some of the most critical functions of its tube fillers. "Our machines employ servo lifts at the point of fill, and servo pumps have replaced lever-activated pumps," says Fredrik Nilsson, sales manager at Norden. "Servomotors allow you to run faster." Norden also offers an all-servo-driven machine.
AMS Filling Systems Inc. (Honey Brook, PA) also employs servomotors in its auger filler heads, which can be mounted on any of the company's semiautomatic and automatic fillers. Mounted above the auger shafts as direct-drive systems, the servomotors can run at much higher cycle rates than a clutch brake–driven machine, says president Brian Baker.
All-Fill offers servo-driven filling systems that fill multiple product lines at once. All-Fill also provides semiautomatic servo-driven systems and continuous-motion rotary systems. These systems can run from 10 to 400 containers per minute.
|Aylward Enterprises's bottle filler has 30 counting wheels, each of which has its own servomotor.|
Machinery from ProSys Innovative Packaging Equipment (Webb City, MO) first employed servomotors 12 years ago. "At that time, we used them for point-to-point accuracy and speed of container movement through the filling system," explains sales manager Gary Lowden. "Because the technology has improved and costs have dropped, we now utilize them in a variety of areas with the filling station being one of the primary locations. With servo technology, we have the ability to minutely control speed, movement, and force, giving us a filler that has increased versatility by allowing us to run drastically different products, speed up changeover, and adapt production needs accordingly." Servos have been used on and are now a common option on every ProSys model from its single-head cartridge filler to the mutiple-head squeeze tube and syringe fillers.
Servos may also enable machines to maintain better accuracy. "In general, servomotors provide an extremely accurate method of controlling machine movement," says Garrett Geary, regional sales manager for Marchesini Packaging Machinery Inc. (West Caldwell, NJ). "Servo reliability is very high with little, if any, performance degradation."
Matt Neumann, vice president of sales and marketing for Aylward Enterprises (New Bern, NC), which incorporates servo technology into its bottle fillers, explains that servomotors allow the correction of index steps, helping machines maintain accuracy when operating at high speeds. For instance, Mateer Burt's (Exton, PA) servo-driven Neotron System Series 1800D auger filler dispenses to within 0.25% of its target fill weight.
Such control helps to contribute to increased line speeds. "In simpler terms, the more control you have over the auger and the container handling, the quicker the overall line will run. Servomotors provide this additional control," says Dinh. "Servo-driven auger fillers provide optimum auger speed and motion for efficient and accurate product dispensing. Servo-driven indexing conveyors provide accurate container positioning at filling and weighing stations at repeatable times, helping to increase throughput."
To put servomotors to optimum use, machine operators must be thoroughly trained to handle them. Says All-Fill's Dinh, "Training, training, training! You need to have qualified operators who are capable of understanding the features of the machine and who know how to utilize the machine's features to their optimum level."
Because of their simplicity, servomotors may reduce much of the mechanical maintenance necessary with traditional machines, keeping packaging lines in operation. According to Mateer Burt, servo-driven systems have fewer parts than con- ventional clutch brake units. "Fewer parts mean less downtime, reduced maintenance, and fewer replacement parts," explains April Koss, marketing communications manager. Mateer Burt's auger filler can dispense pharmaceutical liquids, creams, powders, and granular products.
|IWKA PacSystems's servo-driven TFS 80 features rapid changeover.|
Nonetheless, machinery operators still need to develop a keen understanding of servomotor technology to keep maintenance to a minimum. According to ProSys's Lowden, "the understanding of the technology and how it works seems to be the biggest hurdle that the field maintenance personnel face. But with proper training and diagnostic understanding, any problems can be readily defined and resolved." He adds that maintenance of servomotor systems is similar to the maintenance required for any electronic device. "Up-front attention to control connections, cooling systems, environment placement, and load applications all help minimize the need for maintenance."
With the latest servo technology and the right knowledge, pharmaceutical packaging professionals can immediately improve the speed and accuracy of their lines, possibly at reduced operating costs. "With our advancements in servo-driven auger filling machines, we have been able to present an economical solution to our customers' demands for much higher cycle rates and more stringent accuracy requirements," says AMS Filling's Baker.
For example, "the use of servo technology on ProSys's HVF R110 cartridge filler took operation from 25 cycles to 45 cycles per minute with an added cost of only 35%," explains Lowden. "The cost of the technology has dropped, helping to make the servo an important part for filling equipment manufacturers and end-users."