BE IN THE KNOW: ROBOTIC VALVE BAG PLACING

There are a variety of valve bags utilized in various industries. If you’re looking to automate your process with a robotic valve bag placer it is important to know that not all valve bags are the same. Most importantly before you select a bag of any kind, you must make sure that the bags are “automation quality”. Even though pricing of a lesser quality bag will be more affordable, you will pay for going cheap in the long run and your brand new, awesome robotic automation will not perform how you want it to.

With that said the variances between bags can be in material; poly, poly-woven, kraft, perforated and non-perforated, in style of valve; tuck in sleeve, extended sleeve, standard, and in valve size, placement, or bag size.

The robotic placer can work with many combinations of these variables. A brief description of some of these combinations are shown below and we have designated if these bags will work with the placer, will not work with the placer, will work with special end effectors or if individual testing is needed to pre-qualify.

• Kraft bag with tuck in sleeve.  This will not work with the robotic placer because of the position and nature of the tuck in sleeve.  The sleeve is thin and flexible. The suction from the placer causes the sleeve to collapse on itself and not allow for spout access to the filling cavity.
• Poly-woven bag with tuck in style sleeve.  Due to the tuck in style sleeve this cannot be placed
• Heavy kraft bag with tuck in sleeve. Due to the tuck in style sleeve this cannot be placed.
• Large kraft bag with tuck in sleeve.  Due to the tuck in style sleeve this cannot be placed.
• Poly-woven bag with normal valve. This will work with the robotic placer utilizing special end effectors do to the material. Poly is light and very flexible. Special end effectors are used to provide stability to the bag during placement.  Testing of the bag is recommended.
• Poly-woven with vinyl/nylon sleeve.  Normal style valve.  All woven bags need to be pre-qualified and approved by testing of the sleeve. Bags that pass the initial test will need special end effectors to provide stability during placement.
• Perforated kraft bag with normal valve.  This will work with standard end effectors.
• Non-perforated kraft bag with normal valve.  This will work with standard end effectors.
• Kraft bag with extended sleeve for ultrasonic sealing.  The bag pictured will work with special end effectors.  Extended sleeve bags must be be pre-qualified and approved by testing of the sleeve to determine if there is ample room for the pick-up of the bag. Bags that pass the initial test will need special end effectors.
• 2 mil kraft with normal valve.  Minimum thickness for proper placement with standard end effectors.
• Perforated kraft bag with normal valve.  This will work with standard end effectors.
• Non-perforated kraft bag with normal valve.  This will work with standard end effectors.

You will notice that many of the kraft bags pictured vary in valve size, bag size or valve placement (left or right).  This is done to show flexibility of the robot.  If all valve sizes and placements are the same but the bag sizes vary, the arm can pick and place without additional training. Its best if the bag magazine is adjustable to assure consistent valve placement. If the valves are varying in size, interchangeable spouts are needed for the filler and the robot will need to be trained for each valve size.

Robot Placers allow for both left hand and right hand valve bags giving it an advantage over mechanical placers.  These are not interchangeable on the same preforming conveyor setup. The robot will need to be trained for each pick position (left or right hand valve). The bag magazine/performer setup will determine if you can use left or right hand bags. If you use a stacked (drawer) style (pictured on the right) you will be in the clear without any other equipment upgrades. If you use bags that are not “automation quality” and need a magazine with pre-former you will not be able to switch between left or right hand bags on the same pre-former setup. This would need to be determined so that the equipment can be designed to the individual job application.

These are just a few examples of the “rules”, but understand that there are always exceptions as bag technology changes.  We encourage, and in some cases demand, that all bags a customer is considering be pre-qualified by our experts in order to provide the best scenario and value to our customers. And don’t forget about “automation quality” bags, you will thank us later.