I am looking for insight on sizing, locating and mounting vibrators on 4 sided hoppers to extend the time before failure of the hopper wall due to cracking.
Most vibrator manufacturers have specific instructions included in their manual for proper installation. Typically, this involves skip-welding channel up the side of the hopper. The channel should extend most of the sloped vertical run of the hopper. Orientation of the vibrators should be shaft horizontal. Location of the vibrators should be in the lower portions of the bin, roughly 1/3rd up the sloped portion vertical height. Also, setup the controls so that the vibrators ONLY RUN when you are emptying. (No reason to run them unless material flow is needed.)
Use good motor protection, like solid-state overloads, since vibrators suffer excessive load if run under high-amplitude conditions, such as on empty bins or upon flimsy mounting. Excessive amplitude will cause motor O/L events.
Mount plates should be flat, and Grade 8 bolts used. After 1-2 hours operation, double-check the bolt tightness, and periodically check these again.
Ideally, this minimizes the run time of the vibrators, minimizes their amplitude (they are supposed to cause a "liquifying" or "flow-ability" of the material in the hopper, causing the material to vibrate, not the vibrator, per se), while maximizing the flow of material and the lifetime of the bin.
Also, (over-looked the sizing of vibrators Q), this is based on the weight of the material. What is the material, and what is the volume of the hopper?
This particular hopper (we have 34) is 65.5" long x 30" wide x 49.5" deep, 53" deep to the point of the pyramid. The material is cement which is 90 lbs per cuft. The volumne is 20.08 cuft.
With that size hopper full of cement, rotary electric is probably not your best choice. Better would be piston vibrators, but there still would be clinging buildup on the inside walls, which can fall off in chunks, causing blockage. Do you have compressed air available? If so, take a look at Workmaster Bin Butlers. These are a miniature form of air cannon, except their output is a radial pattern, operating somewhat like an air-knife. They work well in breaking up the bridging and clinging that this material is likely to do, and they would never damage the hopper. Take a look at:
It's good you have air, and also your air consumption will go down appreciably by using these devices. Have you seen the numbers on consumption costs? A receiver tank might be needed, due to the momentary demand needs being more than your current air supply, but then this would recharge between firings.
