Delta Pure Filtration manufactures string wound filters in a wide variety of material and format combinations to meet the requirements of a wide range of depth filtration applications. Regardless of chemical, temperature, micron rating, size or end fitting, Delta Pure Filtration is likely to be able to satisfy your string wound filter requirements.
Delta Pure Filtration manufactures an array of filter types: string wound, melt blown, carbon filters, and various combinations (such as melt blown over carbon, string wound over melt blown, etc.) of these for enhanced performance
Benefits of String Wound Filters from Delta Pure Filtration
String wound filters from Delta Pure Filtration have been tested and then selected by our customers’ process engineers after satisfying demanding requirements, including particle counts for submicron particles, filter life, and overall economics. We are able to tailor and customize winding patterns using computer-assisted modeling.
We have been a reliable supplier since 1983. We pride ourselves on fast deliveries, excellent quality, and consistent products. We keep a large inventory of raw materials and have developed excellent relationships with our suppliers to provide short lead times.
We manufacture string wound filters from 2” to 72” lengths, and 1.5” to 6” diameters. We offer over 18 different filter media (yarn, roving or string) and more than 11 types of cores – but these numbers are constantly increasing! In addition, we offer a variety of end fittings, core covers, and end configurations.
Center Core Selection Guide for String Wound Filters
Polypropylene String Wound Filter Cores:
This core is an economical choice for water, aqueous fluids over a broad pH range and broad range of organic chemicals. Typical maximum usage is 180 F (82 C).
Glass Filled Polypropylene String Wound Filter Cores:
Where polypropylene is chemically compatible and where added strength is required for slightly elevated temperatures (because unreinforced polypropylene will soften more significantly), a glass filled polypropylene core may be the answer. Suggested maximum temperature in compatible fluids is 200°F (93°C).
Tin Plated Steel String Wound Filter Cores:
This is a metal core for solvents, oils and paints and for elevated temperatures. Maximum temperature in compatible fluids is 400 F (204 C).
304 Stainless Steel String Wound Filter Cores:
For corrosive solutions or with chemicals that would cause polypropylene to swell or soften, and where other process components (tanks, piping, etc.) are 304 sst, a grade 304 sst core is often the right choice. Maximum temperature in compatible fluids is 750 F (399 C).
316 Stainless Steel String Wound Filter Cores:
For some acids and corrosive organics, a 316 stainless steel core may be more suitable than one of 304 stainless steel. If process equipment (tanks, pipes, etc.) are 316 stainless steel, then a 316 stainless steel core may also be preferred. Keep in mind, however, that process components are generally designed to last for decades, while a filter may be changed-out after days, weeks or months in service. Maximum temperature in compatible fluids is 750 F (399 C).
Nylon String Wound Filter Cores:
This is a good material for many fuels and organic chemicals. Suggested maximum temperature in compatible fluids is 275°F (135°C).
Polyester String Wound Filter Cores:
This is a good core material for many fuels and oils, and many caustics. Suggested maximum temperature in compatible fluids is 300°F (149°C).
PVDF String Wound Filter Cores:
PVDF is a premium priced fluoropolymer material and provides compatibility with a range of acids, oxidizing chemicals, fuels and oils. Suggested max temperature in compatible fluids is 250°F (121°C).
PTFE String Wound Filter Cores:
PTFE is a premium priced fluoropolymer material and when used in a core provides an extremely wide range of chemical compatibility. Suggested maximum temperature in compatible fluids is 300°F (149°C)
String Wound Filter Media Selection Guide
Industrial Polypropylene (03) String Wound Filters
String Wound Filters with Industrial Polypropylene media are used for a broad range aqueous chemicals over a broad pH range (acid and caustic), many organic chemicals, and water. Typical maximum usage is 180 F (82 C).
“FDA” Polypropylene (01) String Wound Filters
String Wound Filters with “FDA” Polypropylene per FDA CFR 177.1520 are used in a range of food, beverage, cosmetic, pharmaceutical, and potable-water applications. Note: filters certified to NSF/ANSI 61 are available. Typical maximum usage temperature is 180 F (82 C).
Antimicrobial Polypropylene (20) String Wound Filters
String wound filters with blue-colored polypropylene yarn (containing a silver ion – antimicrobial agent are used in drinking water, fountain, pool and spa applications where there is a desire to prevent or reduce microbiological growth inside or on the surface of a filter. The antimicrobial agent is EPA-registered, NSF listed and FDA-listed and is claimed effective against 650 strains of bacteria, yeast, fungi and molds. (This filter medium does not sterilize liquids; it merely inhibits the growth of microbes.) Typical maximum usage temperature is 140 F (60 C).
Fibrillated Polypropylene (02) String Wound Filters
String wound filters made from fibrillated polypropylene are used in ultra-pure liquids, electronics, and plating applications where non-leaching is critical. Rather than being made from short fibers, this filter medium is made from a non-migrating slit film polypropylene which reduces extractables. Chemical resistance is equal to standard polypropylene. The typical maximum usage temperature is 180 F (82 C).
Natural Cotton (44) String Wound Filters
String wound filters made from natural cotton are used for oils, paints, organic solvents, alcohols, petroleum and some waste water streams. Typical maximum usage temperature is 250 F (121 C).
Natural Cotton Blend (04) String Wound Filters
String wound filters made from natural cotton blend (comprised of natural cotton and some polyester fibers) are used for oils, paints, organic solvents, alcohols, petroleum and some waste water streams. Typical maximum usage temperature is 250 F (121 C).
White Cotton (05) String Wound Filters
String wound filters made white cotton (bleached cotton on the outside of the yarn, natural cotton in the center of the yarn) are used for oils, paints, organic solvents, alcohols, petroleum, amines, and a variety of chemicals and chemical intermediates. Typical maximum usage temperature is 250 F (121 C).
FDA Bleached Cotton (06) String Wound Filters
String wound filters made “FDA Bleached Cotton” are used for oils, paints, organic solvents, alcohols, petroleum and a variety of chemicals and chemical intermediates. They are also used for food, beverage, and pharmaceutical applications. Typical maximum usage temperature is 250 F (121 C).
Rayon (09) String Wound Filters
String wound filters made from Rayon are used for oils, paints, organic solvents, alcohols, petroleum and a variety of chemicals and chemical intermediates. This grade of material is a so called “FDA grade” Rayon per relevant sections of 21 CFR 177, and as such, these filters are also used for food, beverage, and pharmaceutical applications. The chemical compatibility of Rayon is similar to cotton as they are both cellulosic materials. The typical maximum usage temperature is 275 F (135 C).
Polyester (13) String Wound Filters
String wound filters made from polyester are used for many fuels, oils, organic chemicals and many caustics. The typical maximum temperature in compatible fluids is 300°F (149°C).
Nylon 6,6 (11) String Wound Filters
String wound filters made from nylon 6,6 are used for organic solvents and caustic (alkaline) chemicals. The suggested maximum temperature in compatible fluids is 275°F (135°C).
Glass (15) String Wound Filters
Our corrosion resistant grade of glass does not use petroleum based lubricant. (Other grades of glass that use petroleum lubricant should be baked to try to remove as much of the lubricant as possible – we don’t use that type of glass.) String wound filters made with a glass filter medium are used for organic solvents, high temperature fluids, fuels and oils, and some weak acids. The suggested maximum temperature in compatible fluids is 750°F (398°C)
Ryton® Polyphenylene Sulfide PPS (18) String Wound Filters
Popular trade names for PPS materials are RYTON® and TORCON®. String wound filters made from PPS are often used for hot water, automotive fluids, glycols, caustics (high pH solutions), many organic chemicals, and some acids. The suggested maximum temperature in compatible fluids is 400 F (204 C).
Note: RYTON is a trademark of CHEVRON PHILLIPS CHEMICAL COMPANY
Note: TORCON® is a trademark of TORAY
Conex® (21) String Wound Filters
Popular trade names for heat resistant meta-aramids are CONEX® and NOMEX®. String wound filters made with Conex are used for applications where there is concern about oxidation or a need for flame resistance, for caustics, and for many organic chemicals.
Note: CONEX® is trademark of Teijin
Note: NOMEX® is trademark of Dupont
Acrylic R (66) String Wound Filters
This filter medium is made using high molecular weight polacrylonitrile which is extremely resistant to hydrolysis. String wound filters made with Acrylic R are typically used for electroplating chemicals and for acidic (low pH) solutions.
Specialty String Wound Filters from Delta Pure Filtration
DW Series – NSF 61 polypropylene string wound filter cartridges are certified to comply with materials safety requirements of NSF/ANSI 61 – “Drinking water system components- Health effects”. These filters are manufactured to be used by water municipalities and in various point-of- entry (POE) potable water systems. In addition, these filters are made using polypropylene complying with FDA CFR 177.1520.
HC series filters are wound with two zones in order to provide longer filter life with challenging fluids. A more open pre-filtration section serves to protect the downstream section and remove larger particles, while a tighter final filter section provides removal of smaller particulates.
CN04 & DCB Series Carbon/Sediment Cartridges are dual media cartridges (string wound over carbon) which provide removal of chlorine, chemical contamination and sediment. The cartridges also improve the taste and odor of water. The CN04 utilizes an inner carbon impregnated medium and the DCB has an extruded activated carbon block center core. The carbon is wrapped with Polypropylene, Bleached Cotton or Anti-Microbial Polypropylene media to enhance the life and performance of the carbon.
The FUSION™ DWMC Series Liquid Filters from Delta Pure Filtration feature “Melt Blown media on the inside for confidence, and Precision String Wound media on the outside for performance.” By fusing melt blown and string wound technology into the same filters, Delta Pure Filtration can help customers achieve longer filter life and cleaner fluids.
Electrically conductive String Wound Filters:
Super Absorbent Polymer String Wound Filters:
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"I've been doing business with Delta Pure for many years and you will find that all of the people there are real stand up folk."
- Marshall B.
“Delta Pure has been one of my manufacturers that will drop everything to help my customers out of a bind. I have called them at the drop of a hat to do an emergency order and no matter how small or large the order has been they have always come through for me and my customers. Delta Pure has been available to me days, nights and weekends, almost without fail. We have been able to offer our customers the DP product as a replacement / alternate for manufacturers that our customers have been set on for years and the DP filter has been tested and approved by many of our major customers across the USA.
We appreciate their ability to work with us on customizing filters and their dedication to customer service that I find so lacking in some of the manufacturers in our industry in today’s world. Donna and Steve are always willing to jump right in with both feel to assist in a resolution to issues that come up – even on Friday at 4:45PM.”
“Over the last few months the team at Delta Pure has been truly jumping through hoops to supply desperately needed string-wound filters to our customers. I can tell you that this dedication to excellence has enabled us to drive sales deeper and wider into these accounts and engendered total trust from our contacts.. When we sell your products to our customers we stand behind the Delta Pure name and I can tell you that this is easy to do as your outstanding reputation is well-deserved.
Thank you again for the hard work and late hours your team has put in to make our joint efforts count when it’s most needed in the plant.”