Pentalift News Blog
How does a lift table hydraulic velocity fuse work?
December 13, 2019, 10:53 am - If this option is ordered the hydraulic velocity fuse is installed in the return line of the lift table’s hydraulic circuit. As the lift table starts to lower the hydraulic oil flows out of the lift cylinder(s) and through the velocity fuse to the power unit reservoir. Depending on the model of lift table the velocity fuse is installed directly on the base of the lift cylinder or in a common manifold that monitors the returning oil flow rate from a bank of multiple lift cylinders. Velocity fuses are readily available commonly used and rated in GPM (gallons per minute) of hydraulic flow. For example a 5 GPM rated velocity fuse will allow up to 5 gallons per minute of hydraulic oil to flow freely through the valve without mechanical interruption. In the rare event of a hydraulic line rupture with a loaded lift table in the raised position the hydraulic oil flow rate leaving the lift cylinder(s) will increase both immediately and significantly. If this increased flow rate exceeds the velocity fuse rating an internal valve in the velocity fuse mechanically closes instantly trapping the oil in the cylinder(s) and successfully arresting the downfall of the lift table.
What is dock equipment pit curb angle and who provides it at a construction site?
December 6, 2019, 3:30 pm - Dock levelers and dock lifts are 2 of the most common products used at a loading dock area and are generally installed into a pre-formed concrete pit. Prior to the equipment arriving at the construction site the pits are first formed. The pit curb angle is required at that time to form the pit to the manufacturer’s specified length, width and depth. The pit curb angle is manufactured from steel angle iron and has tangs or J bolts welded to the inside of the angle for the concrete to “knit” around when the concrete is poured. As the concrete cures these tangs or J bolts solidly secure the curb angles in position. Although pit curb angle is often available it is seldom ordered by the contractor directly from the manufacturer. The primary reason is the pits are often formed well before the dock equipment is required on site, often months in advance. The total costs for the manufacturer to supply and ship the curb angle ahead of the equipment can significantly exceed the cost of sourcing the pit curb angle locally. Sourcing the curb angle locally also minimizes any potential for mis placed or damaged goods that can occur during shipment from the manufacturer. Traditionally it is most common for the contractor to source the curb angle locally through a miscellaneous metal supplier; the local miscellaneous metal supplier fabricates the curb angle to the manufacturer’s pit drawing guidelines.
What are the most common lift table capacity ratings?
November 29, 2019, 3:03 pm - The overall lifting capacity is the most common and most referred to rating on a lift table. The overall rating is based on an evenly distributed load and these ratings typically range from 500 lbs to 20,000 lbs. Lift tables that are used to accommodate a rolling load such as a pallet truck or rolls of paper, coils of steel etc. have 2 additional capacity ratings; single axle end load and single axle side load ratings. The end and side load capacity ratings only apply when the lift table is in any raised position during load transfer on or off the platform. The lift table is designed to accommodate a higher rolling load transferring over the ends of the platform than the same rolling load transferring over the sides of the platform, hence the 2 ratings. Transferring product over the ends of the platform assures that the load is travelling with the length of the scissor legs providing the maximum stability. On occasion it is necessary to transfer the product over the sides of the platform when the lift table is in the raised position. In this application the load is now travelling across the length of the scissor legs resulting in a lower single axle side load rating. For example a 10,000 lb capacity lift table is often rated as follows. Lifting capacity 10,000 lbs based on an evenly distributed load. The same lift table is often rated at 8,000 lbs single axle load capacity across the platform ends and 6,300 lbs single axle load capacity across the platform sides. In an application with a rolling load going on or off the lift table platform in the raised position it is very important to know the traffic flow to best determine the appropriate capacity rating.
Can you use a Lift Truck on a Dock Lift?
November 22, 2019, 2:32 pm - Although it is not very common you can use a lift truck on a dock lift if the dock lift is properly sized, rated and equipped. Some of the factors to first consider. The dock lift platform size should accommodate the overall length of the lift truck with the longest load that the lift truck will be carrying. The width of the dock lift should be sized to allow the lift truck operator to exit the lift truck and move around freely on the platform. When selecting the dock lift capacity consider a combination of the overall weight of the empty lift truck plus the maximum load weight that the lift truck is rated to carry. Higher capacity dock lifts are often rated in 5,000 lb increments; select the next capacity higher than the total of the weight to be lifted. A very common option for this application is equipping the dock lift with an Automatic Hydraulic Roll Off Stop. The automatic roll off stop is a powered bridge plate installed on the end of the dock lift platform opposite the truck end. When the dock lift is in the lowered position the automatic roll off stop is flat and level allowing the lift truck to drive across it and onto the dock lift platform. As soon as the lift button is activated the automatic hydraulic roll off stop immediately powers upward into the almost vertical position behind the lift truck. The roll off stop now acts as a barrier to prevent the lift truck from accidentally driving off the dock lift when it is in the raised position. When the dock lift is returned to the fully lowered position the hydraulic roll off stop automatically retracts to the flat level position. The lift truck can now safely exit the dock lift platform.
Where are tilting systems often used in industrial applications?
November 15, 2019, 11:52 am - Working with bins of bulk product can often be challenging for the machine operator. The challenges arise because of the repetitive bending and stretching required reaching down into the bin to load or unload components. In this application consider if the product bin is first loaded onto an industrial hydraulic tilter. Under operator control the bin can now be tilted into the most ergonomically correct and comfortable position for the operator to retrieve or place the components in the bin. Tilters are also often used during the manufacturing assembly process. When production planners address ergonomic, safety and productivity topics it is not uncommon for components to be added to an assembly in a tilted position, assembly then lowered, packaged and prepared for shipping or sent to the next assembly cell. The most common tilters use a hydraulic or pneumatic operating system and tilt up to 45 degrees. Custom tilters or work positioners are also available to suit a wide range of applications.
