Bulk Material Flow Control Gates (Part 1)
Posted on Thursday Apr 04, 2019 at 05:25PM in Belting & Conveyors
Producing, processing, transporting, and using bulk materials requires gates to control the volume and direction of material flow. Purvis Industries can provide state of the art flow control gates of all different types. Purvis Industries’ standard gates are designed for bulk material of highly abrasive material with bulk densities of up to 120 PCF. This blog will describe several of the standard gate types we offer and briefly describe their operation and use.
Horizontal Slide Gates
- These gates may be single or double blade gates of standard or custom sizes. When closed these gates stop the flow of material and when open allow the material to flow freely. When required the gate position can be modulated to control the rate of material flow.
Horizontal slide gates consist of a gate frame, gate blade supports, blade support protection liners, blade support quick inspection and replacement equipment, gate blades, gate blade actuators, gate blade position indicators, one touch doors to facilitate access to the actuator to blade attachments, and unique hermetic seals. The standard gate actuators are hydraulic cylinders. Options are available for electrical, pneumatic, or manual actuation. Standard gate blades are made of 360 BHN steel plate lined with 7 ga. stainless steel. Gate blade supports are special UHMW blocks designed to minimize gate blade wear and gate maintenance.
Several options can be ordered with these gates. Blade position indicators, a very wide range of operational controls, dust tight seals of proprietary designs, high gate speeds, and precision gate blade position control are a few of the most requested options.
Standard sizes of single blade horizontal slide gates are 24” to 60” width and 24” to 60” stroke. Standard sizes of double blade horizontal slide gates are 24’ to 60” width and 48” to 60” stroke.
Rack and Pinion Gates
- These gates may be single or double blade gates of standard or custom sizes. When shut these gates stop the flow of material and when open allow the material to flow freely. The gate position can be adjusted to set the rate of material flow. The gate blades are made of 360 BHN steel plate lined with 7 ga. stainless steel plate. The blade supports may be specially designed UHMW blocks or cam followers.
- Rack and pinion gates are generally operated by a hand wheel or chain wheel attached to a gear reducer. The force required to open a gate is limited to not more than 50 lb.
- These gates consist of steel frames with perimeter openings into which round rods may be manually inserted. When all rods are inserted, material flow is shut off. This is sometimes done to facilitate maintenance downstream of the gate. Rods can also be inserted to control the flow of material through the gate.
- Standard rod gate sizes are 24” to 60” wide and 24” to 60” long.
- Diverter gates are used to direct material in the desired direction. Purvis Industries’ standard diverter gates are built of ¼” mild steel plate with 3/8” 400 BHN liners in wear areas. The gate blades are 3/8” mild steel plate welded to a round shaft supported as required by internal stiffeners. Blade liners are 3/8” 400 BHN steel plate. Standard outlets for the diverter gates will be 30 degrees or 0 degrees from vertical.
- Each gate blade will be equipped with a removable panel to facilitate blade removal for maintenance without having to remove the entire gate.
- The gates will be 18” square inlet with two or three 18” square outlets. Each blade shaft will be supported by two flange bearings bolted to the gate body. A torque arm will be attached to each shaft to transfer the torque to rotate the blade. The standard torque arm actuator will be a hydraulic cylinder. Alternate actuators may be electric, pneumatic, or manual.