A ready-to-eat cereal manufacturer needed to increase capacity of an existing processing line upstream of a previously installed Slipstick, a horizontal motion conveyor, by 13%. The manufacturer approached Triple/S Dynamics (Dallas) for options.
Slipstick suspension rod
The Slipstick was installed in 1995, and was originally designed for a throughput capacity of 250 lb/min. The customer had already increased the capacity to 266 lb/min without making any changes to the conveyor. Triple/S Dynamics reviewed the conveyor sizing calculations and found that the product bed depth at the desired capacity increase would exceed the usable pan depth of the existing conveyor. The company provided the customer with proposals to modify the existing conveyor by installing a wider conveyor pan on the existing Slipstick drive.
Unfortunately, the customer did not have funding available at the time to replace the conveyor pan. The customer needed a quick, low-cost option to increase the throughput capacity to 300 lb/min. Triple/S Dynamics worked with the customer to determine that there was sufficient clearance between the conveyor and the upstream and downstream equipment to allow it to be sloped downhill ½ degree by adjusting the existing suspension rods used to support the conveyor from the customer’s ceiling or overhead steel. The Slipstick suspension rods are designed with ±6 in. of vertical adjustment for ease of conveyor installation and leveling. Sloping the conveyor downhill increased the product travel rate from the inlet to the drop gates, feeding a series of surge bins and allowing the customer to achieve the desired 300 lb/min throughput capacity without spending any money on parts to modify the conveyor.
The versatile suspension rods consist of two cast stainless-steel rubber bushed rod ends that are threaded into a stainless tube sized to accommodate the required conveyor elevation. The suspension rods are typically used to ceiling-suspend conveyors, but can also be inverted for floor-supported conveyor installations. The suspension rod tube is designed like a turnbuckle with right-hand threads at one end and left-hand threads at the opposite end. That allows the ±6-in. adjustment range of the suspension rod to be easily adjusted in place by simply loosening the jam nuts and turning the tube with an open-end wrench. This eliminates the need for chain falls or jacks to temporarily lift and support the pan for leveling or, as in this case, to change the pan angle from horizontal to sloping downhill.
Since the conveyor could be easily sloped without any new parts required, the customer was able to quickly perform an in-plant test to confirm that the pan slope would provide the desired capacity increase. The test results are listed in the table below.
Results of in-plant test.
Even though this Slipstick drive had been in operation since 1995, no drive replacement parts were required for this capacity increase. The simple, robust design of the Slipstick drive provides years of trouble-free service with periodic lubrication being the only routine maintenance requirement. Typically, the drive will run for more than 20 years before a rebuild is required.
The drive can typically handle modifications to the original conveyor design without any changes. If needed, however, the drive weight stack can easily be increased in size. The long run investment in a larger heavy-duty horizontal motion conveyor outweighs those for a lighter-weight horizontal motion conveyor with a smaller drive size. A smaller drive size would not have been capable of handling the increased product capacity required for this application, and purchasing a new drive or a complete new conveyor would have been necessary.
The desired capacity increase from 266 to 300 lb/min was achieved. Conveying capacity can be increased without replacing the conveyor or spending any money on parts.
Triple/S Dynamics (Dallas) is a leading manufacturer of horizontal motion conveyor systems and screening and separation equipment for a variety of processing industries. With more than 120 years of service, Triple/S offers rugged, safe, sanitary, and reliable processing equipment for the mining, food processing, recycling, bulk handling, agriculture, chemical processing, and foundry industries. For more information, visit www.sssdynamics.com.