During this project, the customer required a series of non-standard liquid filter bags, mostly in nylon, with a very specific size — inner diameter 85 mm, outer 85.5 mm, and length 305 mm.
These are smaller than the standard size 1/2 bags, so the first step for us was to design and open a new plastic ring mold to match their system.
In precision liquid filtration applications such as coating, cooling, and cleaning systems, customers often require non-standard filter bag dimensions with special diameter, length, or sealing structure.
To meet these customized demands, SFFILTECH provides engineering-grade filtration solutions, covering mold development, frame welding, and material performance testing.
All filters are double-layer nylon mesh (PA) with heat-sealed or thermo-welded plastic frames, designed for fine particle removal and high flow performance.
Product |
Micron Rating |
Internal Diameter |
External Diameter |
Length |
Construction |
Sealing Type |
Nylon Bag Filter |
5 µm |
85 mm |
85.5 mm |
305 mm |
Double-layer nylon |
Plastic frame – Heat sealed |
Nylon Bag Filter |
10 µm |
85 mm |
85.5 mm |
305 mm |
Double-layer nylon |
Plastic frame – Heat sealed |
Nylon Bag Filter |
25 µm |
85 mm |
85.5 mm |
305 mm |
Double-layer nylon |
Plastic frame – Thermo-welded |
Nylon Bag Filter |
50 µm |
85 mm |
85.5 mm |
305 mm |
Double-layer nylon |
Plastic ring – Heat sealed |
Nylon Bag Filter |
100 µm |
85 mm |
85.5 mm |
305 mm |
Double-layer nylon |
Plastic frame – Thermo-welded |
Nylon Bag Filter |
150 µm |
85 mm |
85.5 mm |
305 mm |
Double-layer nylon |
Plastic frame – Thermo-welded |
Termination characteristic code: P"x"***
Customization: Full OEM available upon technical drawing or sample.
Product |
Micron Rating |
Diameter |
Length |
Material |
Special Feature |
PP Filter Bag |
5 µm |
178 mm |
813 mm |
Polypropylene |
Standard heat-sealed |
PP Filter Bag |
10 µm |
178 mm |
813 mm |
Polypropylene |
Standard heat-sealed |
PP Filter Bag |
25 µm |
178 mm |
813 mm |
Polypropylene |
Standard heat-sealed |
PP Filter Bag (Anti-Oil) |
25 µm |
178 mm |
813 mm |
PP Anti-Oil Fabric |
Heat-sealed |
Type |
Material |
Width |
Weight |
Thickness |
Large Blanket Filter |
PP / PE |
705 mm |
35 g/m² |
0.3 mm |
Small Blanket Filter |
PP / PE |
505 mm |
35 g/m² |
0.3 mm |
How we make the liquid filter bag for them in professional way?
How we offer one formal quotation in professional way?
Because the nylon filter bags required a special 85 mm plastic frame (non-standard size),
SFFILTECH’s engineering team designed and opened a custom injection mold to ensure precise fitting and smooth sealing edge.
We optimized:
Ring thickness and diameter tolerance
Groove geometry for welding compatibility
Matching with customer’s existing filter housing system
Each filter bag is thermo-welded using controlled temperature fusion to achieve:
Uniform sealing with zero leakage
Firm bonding between frame and double-layer mesh
Long-term stability under flow and temperature fluctuation
All nylon filter fabrics (5–150 microns) and polypropylene felts were tested for:
Air permeability
Bursting strength
Micron retention accuracy
Thermal resistance (up to 120°C)
Chemical compatibility with coolant and coating media
Technical datasheets were provided for client approval before mass production.
After confirming the design and technical validation,
SFFILTECH supplied:
Engineering drawing (STEP format) of liquid filter bag top and whole filter bag drawing for customer reference
Material datasheet (PP / Nylon) for this liquid filter bag
Customized quotation for small-batch trial order
Optional support for filter media roll supply (hot air cotton / melt-blown layer) for assembly testing
For me, i think total five reason:
Full Engineering Support – from drawing to mold and finished product
Precision Manufacturing – strict quality control for dimension & sealing accuracy
Flexible Customization – small-batch OEM accepted
Fast Prototyping – mold opening and sample delivery within 10–15 days
Global Experience – filtration supply for automotive, paint, and chemical industries
Parameter |
Value |
Micron Range |
5–150 µm |
Bag Length |
305 mm / 813 mm |
Ring Type |
Plastic (custom 85 mm mold) |
Sealing |
Heat sealed / Thermo-welded |
Media |
Nylon / Polypropylene / Polyester |
Temperature Resistance |
120°C (continuous) |
Chemical Resistance |
Acid, alkali, oil, solvent |
Flow Direction |
From inside to outside |
We have confidence to offer right liquid filter bag for you, if you come to us.