HAYFLOW refers to a proprietary style of filter bag and restrainer (support) basket which can be installed in both new or existing #2 size bag filter chambers to increase your filtration surface area by 70%.  The restrainer basket has the appearance of a standard support basket with the addition of another inverted basket within.  This support basket geometry not only increases surface area but also reduces the liquid volume trapped within a clogged filter bag, thus reducing loss of product via carry-out waste.

 

A conventional #2 size filter bag has about 5 SQFT of surface area, having a 7" diameter and 32" length.  The restrainer basket for these filter bags consists of a simple tubular shape about 7" diameter and 31" long having 9/64" perforations.  The HAYFLOW style restrainer basket with its "basket-in-a-basket" design increases the surface area by 70%, but also requires a filter bag having that same shape.  The HAYFLOW consists of three components, the support basket, filter bag and flow diverting cap which is responsible for funneling the liquid downwards between either side of the HAYFLOW filter bag.  This flow funnel creates a laminar flow which has a tendency to propel larger solids right to the bottom, leaving the surrounding filter bag area for retention of finer particles.

 

The approximate 8.5 SQFT of surface area will actually last about 5 times longer than standard felt filter bags because the HAYFLOW filter bags are made of a thicker material to provide depth filtration in addition to surface filtration.  While the HAYFLOW restrainer basket and filter bags cost more than a conventional support basket and filter bag, the reduction in replacement frequency includes reduction in labor, liquid carry-out loss, annual replacement filter bag cost, inventory and disposal costs.

 

HAYFLOW supports higher flow rates

The increased surface area provided by HAYFLOW can also benefit applications having higher flow rates or particulate loads.  Even though a #2 size bag filter housing can handle flow rates within the 180-200 GPM range, that flow rate is only applicable to using the housing with only a support basket, akin to a basket strainer.  Nominally rated #2 size filter bags are generally restricted to around 130 GPM and that capacity is reduced significantly as the efficiency of the filter bag is increased.  Therefore there are times when two or more filter bag chambers are required for an application; sometimes this is driven by particle load or differential pressure and not the flow rate.  Especially when retrofitting an existing system, HAYFLOW can provide significant savings.

 

Let's take the example of a water-like fluid being filtered to 50 microns and having a flow rate of 780 GPM.  Using conventional support baskets and filter bags one would require a 6 chamber bag filter housing.  You can save about 30% and use a 4 chamber basg filter housing when using HAYFLOW support baskets and filter bags.  A 6 chamber bag filter made of carbon steel costs about $14,500 whereas a 4 chamber housing costs about $10,200.  The real savings happens when your existing application needs to be re-designed in support of higher flow rates.  Using the example above, let's say your application has been for 500 GPM and you have been using a 4 chamber bag filter, but now you wish to operate a 600 or 700 GPM; rather than spending $14,500 for a 6 chamber bag filter you can simply purchase 4 HAYFLOW support baskets and switch to HAYFLOW filter bags at a cost of only $4,000.

 

Saving product

Loss of product with filter bag changes can add-up on an annual basis, especially for liquids that are "products" and not simply waste water.  If the liquid is aggressive or otherwise dangerous to personnel, HAYFLOW is beneficial because the retained liquid is about 20% of a standard #2 filter bag.  A full HAYFLOW filter bag weighs less than a full conventional filter bag making it much easier and safer for personnel to change them out.