The Solis Accumulator delivers stored material whenever part of a production process must stop, while the balance of the line continues operation, a common condition on a converting or packaging line and one that challenged the machine engineers at Double E for years.
As Product Manager on the Solis Accumulator, Michael McCallum explains, “We needed to design, integrate and program a complete multi-axis machine control system that could handle all the accumulation functions in the drive without the need of a separate PLC, in order to maintain production continuity.” McCallum and his team turned to a closed-loop tension control system from Siemens that enabled the machine ensures consistent moving web tension during a manual splice, plus the ability to change material storage amounts accurately and on-the-fly. The system chosen comprised a Sinamics S120 common DC bus drive system with a Simotics S geared servo motor.
In operation, the system functions as its own tension zone by means of a servo-driven infeed roller system and an outfeed pneumatic dancer roller. The webbing position on the accumulator allows straight-through web path with easy integration of web guiding and inspection lamps, while the festoon storage height and speed are controlled by a pair of geared servo motors.
In process, the accumulator cycle can be started remotely or locally with the flip of a switch, while the onboard alarms trigger at defined amounts of material. Safety interlocked guards and emergency stops protect the overall system and the operation of the entire machine control is housed on a touch panel HMI. In “sleep mode,” the system runs at a significantly lower power consumption level.
McCallum continues to explain the origin of the Solis Accumulator, “Our customer, a textile manufacturer, works with a wide canvass material that gets coated, then rewound, cut and hand-folded onto pallets. The need to splice often resulted in coating inconsistencies during their operation, an unacceptable condition that represented substantial waste. The coating process involves a dipping operation and the dwell time is obviously impacted by the speed of the line, so delays and stoppages were creating problems.” He further notes there was often a six-minute delay in the line when ends of material required sewing.
After obtaining a number of vendor quotes and solution suggestions, the end user settled on Double E and its Solis Accumulator to remedy this problem, as it presented the lowest overall cost, including substantial material savings and energy cost reductions.
By eliminating the need for a separate PLC, the Siemens solution presented to Double E by account manager Hue Liu and consulting engineer Bill Gilbert represented exactly the right combination of cost efficiency and material saving desired by both the builder and the end user, according to McCallum.
As a further advantage, the tension and drive control solution utilized standard application components from the Siemens Converting Toolbox. The Converting Toolbox is a compilation of converting machine functions designed to increase machine performance and aid in engineering time savings. The Converting Toolbox software is provided to customers without cost by the company. This has proven quite helpful, as Double E has secured the building of additional machines for different plant locations of this same customer.
“Using the HMI as a direct connection to the line, without a separate PLC involved,” McCallum points out, “meant a further reduction in capital expense for us. The feature has helped us open other market application opportunities for the Solis Accumulator, since the products from Siemens are standard and we can essentially plug and play many components, including motors, drives, gearmotors, adapters and HMI, adapting them as needed for our customers.” He also cited the global support and application engineering made Siemens a logical partner for both US and international customers of Double E. While converting is the main market for this builder, Double E equipment is found in plants producing rubber hose, air bags, adhesive labels, construction netting and other end products. The Solis Accumulator is used in a variety of applications where coating and laminating are performed.
More info: www.usa.siemens.com/drives, www.ee-co.com