Skirt seals are not normally a problem with bin activators. Some 100,000 or more units have been installed and they are generally very reliable. I have some detailed notes on Bin activator features if you care to send your email address to lyn@ajax.co.uk. Noting the cone angle of 60 degrees indicates that the silo is almost certainly not going to mass flow, which is a great pity for a hygroscopic material as 'caking' is a serious prospect, even with a dry air blanket. It would certainly seem worth while to check the wall friction value and estabish the relatively small change in wall angle that would be needed for mass flow as a positive means to avoid long term dead regions of storage. Alternatively, if the construction is committed, the fitting of 'Lynflow' inserts would be a relatively inexpensive means to generate aive flow pattern. ■

Hello engric99,

I have been at many plants that had bin activators installed and had become ineffective in moving material. Please contact me and I can discuss some options. The thing I would recomend which may be a less expensive solution and does not require major structural changes is a combination of UHMW lining on the cone or slope section and Isobaric Sword Nozzles. These nozzles are used with Air Cannons that blast compressed air via the Isobaric sword and distribute this air throughout the sword's length causing the material to fluidize and flow. These units can be interlcoked with a flow sensing switch that turns them on only when needed to avoid material compression. See attached image so you can have an idea of what this system looks like.

Good Luck !

Lou Gutierrez

Clean Plant Engineering

(561) 713-6541

Attachments

swordJPEG:forum_attachments/file_container/sword.jpg (BMP)

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I would add that for a hygroscopic material it would be prudent to employ a mass flow hopper to prevent dead regions of storage, unless the hopper were to be completely emptied every time before refill. A 60 degree cone is very unlikely to give this flow pattern and powder tests are required to determine the optimum wall angle.

The reasn for considering a bin activator may also be questioned. Apart from the fact that they may not provide extraction aoround the whole periphery of the bin, because powder will take the easiest flow route, they do not save much headroom. Their main virtue is stimulating flow through openings less than the critical arching dimension for poor flow materials, but has the required gravity flow orifice size been determined? I suspect that the application would merit examination by a specialist or at least use a design strategy as attached.

Attachments

flowchart3 (GIF)

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Engric99,

A bin discharger is a very reliable piece of equipment. It usually consists of a conical shell with internal pressure cone, is supported by rubber bushed hanger arms, sealed by a fabric reinforced elastomer, and excited by a vibratory motor.

At Carman Industries, we have thousands of successful installations currently in operation with a couple hundred more shipping each year. Typically, the only items that require replacing are the flexible connectors, hanger arm bushings, and the vibratory motor.

In an indoor installation, all components usually last a minimum of 5-7 years. In outdoor installations, the flexible connectors might need replacing in 3-5 years. Our Parts Department occasionally receives phone calls from customers with bin dischargers older than 10 years who are just now purchasing their first replacement parts.

Please do not hesitate to call us at 800-456-7560 to discuss further.

Mark Payton

Application Manager

www.carmanindustries.com ■