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Frequently Asked Questions

  • What filtration material should I use?
    Before selecting a filter media, you should first identify the chemical and thermal make-up of the fluid you are processing. You can then determine what materials are thermally and chemically compatible with the process. Once you have determined what type of fibre is compatible with the process fluid, determine the type of filtration you want to perform: depth filtration is accomplished with nominally rated felts, surface filtration uses a precise woven mesh. All materials are micron rated to enable the selection of the correct media and achieve the desired level of filtration.
  • What are the types of liquid filtration?
    There are many types of liquid filtration, of which, liquid filter bags and cartridges are two of the most common. While all methods of filtration have their benefits, filter bags are known as an inexpensive, user-friendly solution and are very effective for high flow rate and high dirt load applications.
  • What is differential pressure?
    Differential Pressure (often displayed as PSID, Delta P or ΔP) is the pressure that is created across the filter as the contaminate builds up. The differential pressure is calculated by subtracting the downstream pressure (after the filter) from the upstream pressure (before the filter). Differential Pressure is used as a means of identifying when a filter bag should be changed. The recommended change-out for a filter bag is ΔP = 25 psi.
  • What is a micron?
    "Micron" is a metric unit of measurement defined as 1/1000 of a millimeter (1/24000 of an inch). It is interesting to note that the smallest particle visible to the human eye is 40 microns in size. Contaminate consists of a wide range of particulate. Knowing the size and quantity of contaminate as well as the level of filtration to be achieved (i.e. the quantity of contaminate to be removed from the process stream) is important information in selecting the appropriate filter micron rated media.
  • Which is better, mesh or felt?
    Mesh and felt are very different media and perform differently depending on the application. It is important to understand your process and how it will impact on the filter. One type of media is not necessarily "better" than the other, but simply more suited to your operating conditions.
  • Which is better, a plastic flange top or steel ring top?
    IFM's steel ring bag with side-welded seam is a revolutionary modification that reduces bypass by eliminating the "Lump" common to the standard steel ring fully sewn bag. The Polyform SEAL plastic flange has superior sealing capabilities as compared to steel rings and eliminates the possibility of bypass. In addition, the plastic flange has the advantage of integrated plastic handles for easy bag removal as well as providing the option of a fully welded filter bag. Note, however, that the thermal and chemical compatibility of the filter materials with the process fluid should be considered.
  • What is the difference between polyester and polypropylene felt?
    The difference is primarily the thermal and chemical compatibility. Traditionally the polyester is used on steel ring bags and polypropylene on the plastic flange. Our 100% polypropylene filter bag is manufactured from FDA compliant material for food grade applications.
  • Why does my liquid filter bag seem longer than my support basket?
    Filter bags are basically a two-dimensional flat tube with a collar. It must fill up void spaces of a three-dimensional support basket; therefore, the width of the bottom of the basket is incorporated in the length of the bag. The filter bag must be supported by the basket in order to achieve the maximum differential pressure capacity and prevent bag failure.
  • Do you accept returns?
    In some instances, returns of clean, unopened, filter bags can be accepted with a restocking fee. Acceptance of returns is dependent upon our ability to resell the filter products. Due to the multitude of combinations of media, micron rating, sizes and options, it may be impossible to resell certain bag configurations.
  • What is the flow rate capacity of your filter bags?
    Flow rate capacity is dependent upon a number of process variables such as pressure, viscosity, dirt loading, and desired particle retention rate. Maximum flow rates for standard filter bags based on clean water are listed in the flow rate chart.
  • Why would I choose filter bags over a cartridge?
    Filter bags have five distinct advantages over cartridges. Dirt stays in the bag Greater surface area Lower clean pressure drop Fewer sealing points Easy and quick bag change out
  • Are filter bags FDA approved?
    All fully welded polypropylene felt filter bags with the PolyformSEAL™ plastic flange are manufactured from FDA compliant raw materials.
  • What is your standard box quantity?
    We have a wide variety of box sizes, however our standard packaging is 50 pieces per box.
  • Do you offer private labelling?
    We would be pleased to customize box labels and product tags with your part number and contact information.
  • Do you have a system to filter Biodiesel
    Filter Bags are commonly used to clean old cooking oil to create what is called "biodiesel". Biodiesel applications are usually low flow or batch filtration.
  • Can I clean and reuse my filter bags?
    Felt filter bags are not designed to be cleaned and reused. In some applications, the mesh bags can be cleaned to be reused, but you should inspect the bag to ensure the stitching and material are all intact.
  • How do I know when to change a filter bag?
    Filter bags should be changed out when the differential pressure across the filter bags reaches a maximum of 25 PSID.
  • What is the flow rate capacity of your filter bags?
    This is not an easy question to answer because it requires the consideration of a number of contributing variables such as flow rate, pressure, viscosity, dirt loading, and desired retention rate.
  • Where is Penetanguishene?
    Penetanguishene is located in Ontario, Canada, on the shores of Georgian Bay and home of the 30 000 islands. The name Penetanguishene comes from the Ojibway (an Algonquin Tribe) and it translates to "place of the white rolling sands".
  • How long have you been in business?
    Industrial Filter Manufacturing Ltd. has been manufacturing and servicing the filtration industry since 1979.

This page will help you understand common questions about liquid filter bags

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