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With the launch of our new web site, we’ve added a blog. Here we’ll keep you updated on the latest news and trends for safety in the material handling industry. That may cover many topics, from the latest forecasts for manufacturing and material handling, updates in regulations and standards from OSHA and ANSI, as well as some of our safety gate installations and custom work.

On the blog you’ll also find updates from some of the organizations we belong to, like MHEDA and MHI, as well as MHI’s ProGMA Committee.

We’re looking forward to sharing our news and views with you, and if there is a topic you would like us to touch on, just let us know.

AGVs and the Roly Safety Gate: A Case Study

In one instance, we worked with a customer with a large, multi-level distribution center to equip our Roly® safety gates with the proper technology to interact with their AGVs that were loading and unloading material to pallet drop areas on upper levels. The Roly safety gate model uses dual, counterbalanced gates to maintain a safe environment at all times. The customer sent us the sensors that they wanted to use, and we designed the way our Roly safety systems would detect and interact with the sensors used in the facility.

We equipped the gates with the sensors to allow the AGV to determine if the ledge gate of the Roly safety gate was open or closed. In addition, we mounted photo eyes to the rear post of the gate in order to detect workers that were loading and unloading the pallet loads that the AGVs were providing. Photo eyes worked with the sensors to ensure the ledge-side gate was in place when it detected workers on the platform, providing safety for the workers on the upper levels.

We also installed power operation to each Roly unit and integrated the sensors so that when the ledge gate is up, sensors send information to the AGV, telling it that material can be loaded into the pallet drop area. Once the pallets are loaded into the work area, the sensors send a signal to close the ledge-side of the Roly gate and the workers can then work with the material that was loaded into the area.

As AGVs, robots and other unmanned vehicles continue to be integrated into operations in material handling, we’ll see more need for this kind of wireless control for any device in the facility to make operations more efficient. We can include all kinds of wireless controls to our safety gates in order for machines and employees to operate them - regardless of the gate model, depth, width or height.

Do you have an application that needs safety with added technology? Does your facility have existing safety gates that need to be retrofitted with technology to work with AGVs? Let us know - we can help!

Technology: Incorporating Safety into AGV Pallet Drop Operations

The manufacturing industry is abuzz about the robot revolution. Automatic guided vehicles’ (AGVs) role in the supply chain and material handling has been increasing, and they are increasingly working side by side with humans in facilities like warehouses and distribution centers.

These vehicles, like driverless lift and forktrucks to material moving robots, get integrated into the facility infrastructure and operational processes. AGVs use technology to move throughout the facility - most often using Proximity Laser Scanners and Laser Scanner Interface technologies. These technologies help the AGVs determine objects and locations in the facility, as well as integrate with other facility machinery and equipment.

AGVs are programmed to follow a guidepath - in distribution centers and warehouses, they often move pallets and containers of material from one place to another. With no driver, the machines are being told where to load and unload the materials being moved, often through the use of PLS technology.

The rise of AGVs is allowing material handling systems to grow in size; today’s facilities are much bigger and taller. Warehouses and distribution centers today employ both persons and machines to get the work done more efficiently.

ANSI B56.5 outlines safety standards for the use of AGVs in an industrial facility, but it primarily looks at the space required for the vehicles, load stability, sound requirements and emergency controls for stopping the vehicle. Because the vehicles are driverless, the standards do not look at safety of the workers interacting with vehicles outside of emergency stops and sensors to keep from running into people at ground level.

Even with the AGVs, there is a need to keep the persons working with and around the AGVs safe. It’s still very important to guard areas that material is being passed into...there are also regulations that mandate workers are kept safe in these pallet drop areas - especially upper levels. Dual-gate systems like our line of safety gates are needed to keep workers safe.

Many material handling operations place people in the workstation in which the AGVs are loading and unloading material in pallet drop areas that are two or three stories tall. This scenario is very common and requires fall protection for workers that are working the pallet in these drop areas.

We have worked with many companies that use AGVs in their facilities to integrate the important safety systems into their workflow. To be most efficient and keep operations proficient, is important that the AGV can interact with safety gates. Because they are unmanned, the AGVs need a way to understand if the pallet area is available for unloading and loading material without relying on an employee to perform any extra steps.

Next week we'll outline a job that we did with our Roly safety gate for an operation that uses AGVs.

Safety in Rack Modules: The Case for Rack Supported Systems

Most distribution centers utilize rack modules in their operations in order to maximize storage space and operational efficiency. Rack modules can be designed in a wide variety of configurations depending on the applications. Often these configurations require space for workers to pick from the pallet drop areas throughout the rack structure, or to stack empty pallets and empty totes into open bays.

When workers are involved in these situations, it’s necessary to plan for safety and fall protection. There are a number of ways safety can be achieved, and industry standards like those issued by ANSI and OSHA require a dual-gate system. Safety advantages provided by dual-gate systems, like the models we offer, ensure that workers are safe at all times; when the ledge gate is open, the rear-side gate is closed, preventing the worker from access to the ledge. When the rear-side gate is open, the ledge-side gate closes, providing a safe, enclosed workstation while the bay is picked.

A dual-gate system also keeps the picker a safe distance from the lift truck loading a pallet, as a fixed barrier will be in place while the pallet is being pushed into the bay. This creates a physical barrier between the picker and a pallet being pushed into the area with the force of a lift truck.

A dual-gate safety system is now a standard in the industry, so the decision to install them to secure picking positions and empty pallet return bays is obvious. But the real decision is what type of dual-gate system. There are dual-gate pivot and Roly models, both of which will maintain a safe environment at all times; there are also rack-supported and free-standing gates.

A Pivot Gate has few moving parts and is often the most economical choice, but keep in mind that this design needs room for the gates to pivot, or arc, when operated. When the pivot gate is in use, the ledge-side gate extends out into the truck aisle, and the rear-side gate extends back into the picking aisle. This often is not an issue, but can be if the picking aisle is narrow, or if the lift truck is loading multiple levels.

A Roly Gate solves this issue as the design uses gates that open and close flush within the confines of the rack structure, so the ledge-side gate opens flush with the ledge, and the rear-side gate opens flush with the rear-side column.

Both of these designs are available in both free-standing and rack-supported configurations. When operations needs flexibility, and pallet drop areas frequently move locations within the facility, a freestanding safety gate model can be used efficiently within a rack module. The free-standing gate can be unbolted from the decking, moved to another location, then re-secured. We have seen this work well for some unique material handling operations, and with companies that require a flexible layout.

The other option is Rack-Supported safety gates. This style attaches directly to the existing rack uprights instead of being lagged down into the decking. The rack-supported model has three main advantages over a freestanding model: (1) space savings, (2) more secure connections and (3) cost savings. By utilizing the existing pallet racks for support, the rack-supported model takes up a minimum amount of space in the rack bay, gets tied into the entire rack system and uses few components.

You’ll also have to decide on the size of the safety gate. Because we’re talking about integrating with a rack-module, the existing bay size determines the width of the gate, but you’ll need to decide on the depth and the height that is required. The safety gate needs to be deep enough to accommodate the pallet without being so deep that it projects too far into the picking aisle. With a standard 48” deep pallet, the safety gate should provide a minimum of 56” in clearance to provide room to load the pallet into the area. Because most uprights are only 48” deep, often the safety gate will extend beyond the upright, either back into the picking aisle or into the lift-truck aisle with a platform extension. The safety gate should be made tall enough to accommodate the tallest pallet with some room factored in for fork truck lift-off space, and to allow pickers room to enter the bay to work the pallet, without being too tall that the raised gate is difficult to reach. Sometimes a beam may need to be removed to provide adequate height.

Many dual-gate systems that are both free-standing and rack-supported can be power operated with remote radio frequency controls. To learn more about whether or not to power operate a pallet drop gate, please see this blog post on the subject.

The decision to secure picking positions in a multi-level rack picking module should be an easy one. Where it gets complicated is deciding on which safety gate will best fit your application and how it should be sized and configured. This is where a professional in the industry should be consulted, either through a material handling consultant, distributor, or by reaching out to us.

Safety Gates: To Power or Not to Power

One of the questions we get asked a lot is whether or not to power operate a pallet drop gate. For most applications, we recommend skipping the power option. Manual operation creates the highest level of safety because the operator on the platform, who we are trying to protect, is the only person controlling the opening and closing of the gate. This can be very important for any material handling or manufacturing application.

The majority of the end users inquiring about power operation believe that operations will be slowed unless the fork lift operator can open the safety gate. The concern is that the lift truck operator will go to load a pallet and the gate will be closed. This would cause the operator to get off the truck, climb up the stairs to the mezzanine level, open the gate go back down below to the lift truck to finish loading the pallet.

We agree that this is an issue when using a single-gate system like a sliding gate or a swinging gate. For that type of design, in order ensure safety in the area the gate has to be closed; and in order to load a pallet the gate has to be open.

However, this is not the case when using a dual-gate system, which is the type of guarding that all pallet drop areas should use according to ANSI MH-28.3. When using a dual-gate system, the area can always be safe because the employees working in the pallet drop area can close the rear/operator gate when they are done removing the material to ensure the area is always ready to receive a pallet because the ledge-side gate opens when the rear-side gate closes. As long as the gate is left in this position the area is always ready to receive a pallet so there is no reason to give control to lift truck operators down below.

How to make sure employees close the rear-side gate is a concern of customers who understand the issue with power-operation from below. We have found over the years that this issue gets resolved by communication and training among the operators. More often than not, the position of the gate becomes a signal so when the picking on the mezzanine is ready for the area to be replenished, he/she will toggle the gate, closing the rear-side gate, which opens the ledge side gate. Now the lift truck operator looks up and sees the ledge-side gate open and knows it is time for the area to be replenished.

Sometimes we get asked to power operate the gate because the operator on the lift truck is the same operator that goes up on the mezzanine. But, this scenario is ideal for manual operation because the operator must leave the ledge-side gate open when they go down to the lower level, because if they do not, they will have to go back up to the mezzanine to reverse the position of the dual-gate system. After making that mistake once, they’ll likely remember to always leave the ledge-side gate open for the next time they’ll be loading.



Of course every application is different, and everyone’s operation is different, which is why we do offer the option to purchase our safety gates with power operation. All of those power-operated systems include built-in safety features like photo eyes that detect the presence of a person or object and prevent the gates from closing, along with a clutch that will engage if the gate were to make contact with an object, which is adjustable so it can be set to the proper sensitivity for that specific environment.

The motors are all commercial operators will built-in safety features and numerous controls that can be used, like radio frequency remotes on the lift truck, and flashing lights and caution alarms. But we recommend caution on all of these remote operators, and always advise customers to test the unit in manual operation because they can always add the power option later, which by the way, we’ve never had a customer take that advice and then come back later to add power operation – they always stick with the manual operation. With proper training and education, the manual operation will create the safest environment, and shouldn’t slow down the operation.