Tubular Backwashing Filters

Product Introduction
Designed based on modular concept, the tubular backwashing Filter assembles multiple standard filter units into an automatic filtration system featuring high safety factor. The number of on-line units can be flexibly increased to match varying flow demands. Running automatically with no manual cleaning required, the filter boasts good expandability and allows connection of external high-pressure backwash fluid. Operating under low differential pressure and fitted with V-SLOT filter elements, it delivers thorough backwashing with low liquid consumption. In cases where tough contaminants necessitate manual element cleaning, maintenance and startup operations can be completed easily. The filter purifies process fluid to protect downstream critical equipment, and valuable solid particles can be recovered from backwash drainage. It is applicable for low-viscosity liquids such as raw water, wastewater, gasoline, heavy coking gasoline, diesel fuel and residual oil.
The tubular backwashing Filter is divided into five sub-series:

MFR Series: Automatic backwash by filtrate; cake on outer surface of filter elements is flushed reversely using filtrate from other filter units.
MFV Series: Automatic backwash with external fluid; clean external liquid or gas is adopted to remove surface filter cake.
MFT Series: Manual backwash by filtrate.
MFG Series: Manual backwash with external fluid.
MFC Series: Manual parallel connection type.
Working Principle of Tubular Backwashing Filter

Liquid flows into each filter unit from the main inlet header, penetrates from outside to inside through filter elements, exits each unit and converges at the main outlet header. Solid particles are trapped on the outer surface of filter elements and gradually form filter cake. When differential pressure rises to preset value (normally 70~130 kPa) or the preset cleaning cycle expires, the control system triggers sequential backwashing of individual filter units. While one unit undergoes backwashing, the rest keep normal filtration. Based on backwash medium source, backwash types are split into filtrate backwash (MFR) and external clean fluid backwash (MFV).
Technical Features & Advantages
Simple and reliable structure with only two moving parts: cleaning disc and drain valve
Non-contact cleaning prevents particle extrusion out of elements for excellent contaminant removal efficiency
Stable low differential pressure below 0.011 MPa during cleaning and draining
Ultra-low minimum operating pressure of 30 kPa
Wide flow range: single unit capacity from 30 to 3000 m³/h
Uninterrupted full-flow filtration during self-cleaning cycles
Filtration precision: 0.2~2 mm
Flexible installation: horizontal or vertical layout available
Main Technical Parameters of Modular Self-cleaning Filter

Parameter	MFR Filter	MFV Filter
Backwash Medium	Produced filtrate	External clean liquid or gas
Allowable Viscosity	＜50 cps	＜100 cps
Contaminant Content	＜300 ppm
Minimum Inlet Pressure	＞0.3 MPa	No strict requirement, works below 0.3 MPa
Installation Location	After pump	Before or after pump
Filtration Precision	50~500 μm	20~500 μm
Standard Design Pressure	1.6 MPa / 2.5 MPa / 4.0 MPa
Max Design Temperature	0~250℃ (subject to sealing material)
Quantity of Filter Units	3~24
Unit Valve Size	DN50 (2", max 25 m³/h); DN65 (2½", max 42 m³/h)
Flange Standard	HG20592-2009 (DIN compatible), HG20615-2009 (ANSI B16.5 compatible)
Filter Element Type	V-SLOT slotted metal element (200~2000 μm), POR micropore metal element (1000~2000 μm)
Element Material	316L / Super Duplex Stainless Steel
Piston Rod Material	316L
Shell Wetted Material	304 / 316L / CS / GRP
Anti-corrosion Coating	Nylon 11, Rubber
Shell Seal Material	NBR (standard), VITON (FKM)
Drain Valve	Pneumatic butterfly valve, IP65 protection grade
Utility Supply	0.6 MPa dry clean compressed air; Power: 110V/220V (std)/380V/440V AC, 24V DC

High-performance V-SLOT Precision Filter Element
MF filters are equipped with two optional types of V-SLOT precision metal filter elements:
Type C: Filtration area 2670 cm², for precision ≥125 μm
Type K: Filtration area 3140 cm² (17% larger than Type C), for precision ＜100 μm enabling more compact filter layout
Core Advantages of V-SLOT Elements
V-shaped slots avoid impurity jamming and maintain stable long-term flow rate
Excellent for filtering microfiber, oily sludge and soft agglomerated impurities
Robust structure with no slot deformation under rising differential pressure
Resistant to high forward and reverse pressure load
Precision range: 20~500 μm
Accurate slot width ensures precise filtration
Main body in 304/316L with superior corrosion resistance
Smooth outer surface for convenient manual cleaning
Typical Application Industries & Process Fluids
Industries
Petrochemical, water treatment, papermaking and other sectors
Process Liquids
Petrochemical: Gasoline, diesel, naphtha, FCC slurry, AGO atmospheric gas oil, CGO coker gas oil, VGO vacuum gas oil
Water treatment: Raw water, process water, clarified water, ultra-clarified water, circulating cooling water, spray water, injection water etc.