Low Pressure Pulse Technology

The low pressure pulse technology used in the AC filter delivers considerably more cleaning energy to the filter bags than conventional High Pressure pulse jets or continuous reverse air. The result is more efficient bag cleaning. Low-Pressure technology provides a lower differential pressure across the filter bags. The effect is the number of cleaning cycles is reduced, which lowers your overall operating expenses and extends the life of your filter bags. AC filter cleaning systems require only 7-8 psi air pressure. The low pressure pulse is further enhanced by the use of oval bag frames.

The AC filter bags are oval shaped, with flat sides causing them to flex more during the pulse cycle, enhancing dust cake release for a lower differential pressure across the bags.

Moreover, each bag has a specially designed, heavy-duty frame to support the filter bags. The frames are manufactured from 9 GA galvanized steel instead of industry-standard 11 GA. The heavier wire reduces fatiguing of bag fibers extending bag life.

Oval Snap-in Filter Frames

The AC filter bags snap into place, so no tools are needed to install or remove them. Installation, inspection, and replacement is faster, providing not only lower initial equipment cost, but also lower installation costs. The special metal band sewn into the bag in conjunction with the extended top frame collar assures a positive seal to the tubesheet, without a metal contact.

Also available is a flange top which is attached to the tube sheet by two machine bolts; this insures a positive ground connection is always maintained with bags and frames during operation. No straps or wires are required. With two grounding bolts providing an inherent ground there is no problem with thick paint on the tube sheet or loose straps during maintenance.

Snap-Joint Frames

The new split frame offers a unique patented snap-joint allowing two shorter frames to be connected while inserting the frame into the bag. This provides multiple advantages.

Two piece frames have been manufactured by Air-Cure for years with over one hundred thousand in operation. The new snap-joint eliminates clips and loose parts used by previous two piece frames, making the assembly very simple and fast, just snap the two halves together as the frame is inserted into the bag.

The two piece feature is especially convenient when using 12,16 or 20 foot long frames, or in smaller filters where the frame is longer than the diameter of the casing. Also, the shorter frame pieces are more convenient to handle through the access door. Trying to fit 10 to 12 foot long or longer frames through a six foot access door can be challenging. The two piece frame eliminates this problem without special tools.

Another advantage is the reduction of plenum height needed for installing the bags. Besides the cost savings, the lower silhouette reduces foundation loads, makes onsite assembly easier, and improves the aesthetics. Reduced foundation loads means lower cost concrete foundations or structural steel supports if installed above grade.

Flexibility in Design

The AC filter panelized design involves the filter casing composed of panels, which are flanged for bolted assembly at the plant site. Each panel is formed in a common precision jig to assure similarity, making panels interchangeable within each filter assembly. Each panel is then tagged and marked to an assembly drawing to ease field assembly. Critical panels are pre-assembled in the factory to further insure ease of assembly. This construction must be used for 824 and larger diameter filters because of shipping dimension restrictions, depending on the site.

However, smaller units are available in panelized design because of the low cost, ease of assembly where all welded casings cannot be set with cranes, or for packaging into shipping containers for export. In all situations it offers the lowest cost freight transportation. Another benefit is the ability to change the location of inlets and outlets by relocating the interchangeable panels. This allows the installer to arrange the collector to the optimum arrangement in the field, without extensive pre-engineering.

The all-welded design is practical in smaller filters where the advantage is less field labor therefore lower cost of field assembly. Specialty features such as full factory insulation can be performed to the all-welded design. Larger all-welded filters are shipped with bolt-on inlet scrolls as shown in the lower right image.

Exclusive Bag Cleaning Design

The exclusive pulsing technique in the bag cleaning system prevents re-entrainment of dust particles on a previously cleaned bag. No adjacent or neighboring bag is cleaned in sequence; time delay prevents redeposition of dust. This is accomplished without complex indexing electronics or mechanisms. This results in a uniform airflow and less turbulence, longer bag life and more effective dust collection.

Component Improvements:

New “Air Chamber” bearing design

Manufactured from lightweight aluminum housing. Bronze bearing surface inserts reduces friction.

Scroll-type Inlet:

An integral part of the assembled unit. Internal distribution and baffling devices improve dust distribution and decrease high-velocity zones and turbulence. “Cyclonic” configuration separates dust from the gas stream more effectively reducing dust concentration to the bags. The inlet brings particulate air into the filter to be purified and sent back into the atmosphere.

Rotating Manifold:

A special low-carbon steel manifold provides cleaning air to the filter bags. No blowpipes to disassemble to gain access to the filter bags.

Rotary Positive Displacement Blower:

Could reduce energy consumption by up to 75% with comparable-sized high pressure filters by eliminating the compressor system and you don’t need to add expensive auxiliary equipment to remove moisture, or insulation to your piping system to prevent moisture from forming.

Advanced Diaphragm Valve Operation

AC filters require only one diaphragm and solenoid per filter. That makes inspection and service easier than filters with multiple assemblies. In addition, the new diaphragm is designed to expel gases faster and improve the flow characteristic within the valve better than its predecessors. Faster response of the diaphragm valve results in more effective bag cleaning, lowering operating expense.

Random Sequence Timer

The timer provides a completely random sequence. Adjacent or opposite bags are never cleaned simultaneously. This innovation reduces re-entrainment of dust to bags already cleaned – providing for a more efficient cleaning process.

Additional AC Filter Options…

Stainless steel construction
Variety of filter media selection
Special filter bag spacing
Spray systems with internal piping
Chemical injection systems
CO monitoring
RJ Filter retrofits
Deluge valve system
Differential pressure cleaning
Custom Hopper design
Hopper level detectors
Hopper discharge valves
Hopper overflow drain
Design to NFPA 68 and 77
Skirt Type supports
Custom structural supports
Circular stairway system
Access platform and Ladder
Shop insulation
Custom color selection