Industrial Filtration Systems Boll & Kirch Filterbau / BOLLFILTER

Operating principle of automatic backflushing filtration in aquaBoll series

Automatic strainers engineered by Boll & Kirch Filterbau series aquaBoll operate via a closed hydrodynamic cycle providing non-stop mechanical liquid purification and self-regeneration.

During normal filtration duties, industrial water or cooling fluid passes outward through wire mesh candle elements, retaining particulate debris along interior cylinder walls. As cake builds up, differential pressure increases and is registered by an electronic transmitter.

Upon reaching the preset threshold, the control cabinet opens the flushing valve and activates the rotating backwash arm. Pressure differentials generate high-velocity reverse liquid flow, flushing sludge off the mesh surface into discharge piping in seconds without drop in main line pressure.

Smooth chamber switchover technology in BOLLFILTER Duplex systems

In switchable double filters BOLLFILTER Duplex, process continuity during changeover between an active dirty vessel and a clean standby chamber is maintained by a specialized changeover mechanism. Boll & Kirch utilizes conical plug valves and ball mechanisms engineered with flow channels.

As the handle or pneumatic actuator turns, the internal porting smoothly transfers fluid flow across vessels, preventing pressure surges or cavitation spikes throughout piping manifolds.

For safe maintenance access, the isolated standby chamber is vented through a dedicated drain cock before operators remove service cover bolts to inspect wire mesh baskets.

Selection of filtration mesh rating and candle wire structure for fluids

When designing filtration assemblies, Boll & Kirch engineers configure screen geometry to match fluid viscosity, particulate concentration, and system operating temperatures.

For coarse water pre-filtration protecting pumps and nozzles, perforated sheet baskets or wedge wire grids with openings from 100 to 1000 microns are selected.

For fine purification of engine lube oil and liquid fuels, candle assemblies Kerzenelement featuring multi-layered Dutch weave mesh woven from grade 1.4404 stainless alloy provide absolute retention from 6 to 50 microns.

A rigid internal support tube prevents mesh collapse during pressure peaks up to five bar.

Differential pressure monitoring and DDAT electronic transmitter integration

To ensure continuous diagnostic monitoring of filtration media, BOLLFILTER engineers created visual differential pressure indicators and intelligent digital transmitters DDAT. The instrument connects across filter inlet and outlet ports via stainless piping runs.

Within the measurement chamber, an internal diaphragm deflects proportionally to the pressure differential across the screen.

The electronic DDAT transmitter converts this mechanical displacement into a standardized 4–20 mA current loop signal or digital Modbus protocol, relaying contamination data directly to plant automation consoles for maintenance scheduling.

Ultrasonic cleaning procedure and wire mesh element regeneration protocol

Reusable wire mesh candles and basket inserts manufactured by Boll & Kirch undergo scheduled regeneration to restore flow throughput using dedicated ultrasonic cleaning units Type 5.05.

Once extracted from the filter vessel, candle assemblies are immersed into an ultrasonic tank heated to 60 degrees Celsius containing BOLL-CLEAN fluid.

Powerful piezoceramic transducers generate microscopic cavitation bubbles that implode within wire weave openings, dislodging varnish, bitumen, and mineral particulates from deep mesh pores without damaging delicate wires.

After 20 minutes of ultrasonic treatment, candles are blown dry with clean air and inspected.

Marine fuel oil filtration standards and heavy diesel engine protection

In marine propulsion installations, BOLLFILTER automatic units series Type 6.64 and 6.72 provide essential protection for high-pressure fuel injection equipment against abrasive catalytic fines (aluminum and silicon residues from refining processes).

Purification of heavy fuel oil HFO and low-sulfur VLSFO occurs at operating temperatures up to 150 degrees Celsius, requiring thermal-grade FKM elastomeric seals and steam or electric heating jackets around the filter vessel.

A 10-micron filtration rating shields fuel pump plungers, injector nozzles, and cylinder liners from catastrophic abrasive wear.