The RBE Filter & Swarf Handling System
The RBE filter is a depression type vacuum filter unit in which dirty liquid is contained in the filter tank, above the filter media, the clean section ( suction box ) being below the media is connected directly to the system pump suction.
Filtration of the liquid and chip/swarf removal is achieved by passing the dirty coolant solution through a media covered wedge wire filter screen, this being situated in the tank floor.
The filter screens are manufactured from wedge wire profile 22 in 304 stainless steel, the panels will be interlocking and will be held in position by bolt down clamp plates. The wire section will be 3.2 mm high x 1.7 mm wide (widest part) slot width will be .25 mm, giving 250µ cut off, the media paper will be a 90 gram 25µ cloth.
After passing through the media/wedge wire filter the liquid passes directly via the pump on into the pipework then to the machine tool/s.
The material being filtered will be collected on the media, this will build up to give a 'Filter Cake' and assist the filtration process, the collected solids will be removed during index with the spent media.
The index/regeneration cycle of the filter can be set to actuate on time or on vacuum. The filter will be set to regenerate at certain intervals, at this time the filter media will be advanced by the drag conveyor, during this regeneration cycle the supply of coolant will be uninterrupted, clean liquid will be allowed to flow from the clean tank into the suction box thus breaking any vacuum and allowing full coolant flow to machines during the advance of the media paper. Should the media become blocked prior to the timed interval a vacuum switch will be actuated, this will over ride the timed cycle and instigate the regeneration process.
The conveyor system in the filter will consist of two chains fitted with loose flight bars on a set pitch.
The conveyor drive will through a pair of chain wheels, mounted at the discharge head and driven by a suitably sized motor reduction gearbox. The filter unit will be fabricated in one or more sections from best quality mild steel, the tank walls will be minimum 5 mm, and the ramp and base sections will be a minimum of 10 mm, the sides and base will be supported with angle and channel section steel, the tank will be leak tested.
The tank top areas will be covered in non slip plate where access is required, other areas will be covered in sheet steel plates.
The ramp section will be fully guarded with covers manufactured from sheet steel.
Clean out facilities will be made into the filter suction box, at the front, below ramp section.
For floor mounted filter tanks can be fitted with our optional watertight man access door these are installed at suitable positions in the tank sides.
Dimensions of the tank will be determined by flow and application.
The complete installation will be fully automatic and controlled electrically through a PLC control system.
Coolant Flow & Return System Pipework
Both pipe systems, suction and delivery, will be sized for optimum flow rates and liquid velocity.
Pump delivery pipework will be fitted with pressure gauges.
The pump suction and delivery outlets will be fitted with shut off valves for use in a maintenance condition.
The coolant can be delivered to the machine tools and returned via overhead or under floor pipework, and or flume and conveyor systems.
In the case of returning dirty liquid in pipework, the coolant will be collected at the machine discharge in a sump tank, this will be designed to ensure that the sludge and liquid are elevated and returned to the main filter system for separation and re-filtering.
The sump tank will be complete with high and low level switches, balance pipework, and agitation jetting.
The sump tank will have independent control from both the machine tool and the main filter system this will comprise of a small control station local to each sump tank or machine operator station.
Balled Swarf - Heavy Swarf Loading & Pre-Separation
On the applications producing balled swarf or in the case of heavy swarf loading it is at times recommended that a pre-separation conveyor be incorporated into the coolant/return this will separate a major quantity of balled or heavy swarf before entering the main filter system.
Sizing the System
The total flow requirement of the system is based on requirement of the machine tool/s, the filter system requirements for index cycle purposes, plus volume in circulation, ( in pipework and conveyor/chutes/sumps etc. ). The size of the filter is based on the total flow requirement and type and amount of material contaminate being handled, in this instance on grinding operation this volume is not a consideration in respect of volume.
Agitation jetting sumps
The feed pipework for the sump tank agitation jets will be supplied via the pipe feed to the machine tool header system, a separate feed will be taken from the supply line to the agitation jetting in each collection sump.
The System Filter Pumps Low Pressure
The pumps will normally be horizontal units of a reputable manufacture and will be selected for both suction and delivery characteristics, they would be base mounted and close or long coupled.
All pumps will be fitted with mechanical seals.
High Pressure Pumps
The pumps will be vertical multiple stage units of reputable manufacture and would be selected for both suction and delivery characteristics, it will be base mounted and close coupled. Pumps will be fitted with mechanical seals.
The System Coolant Return Pumps
The pumps will be a vertical mounted, open impeller units and will be selected for both suction and delivery characteristics, they are be mounted in the sump tanks.
Auto Make-up and level control
An automatic level control system can be incorporated. This would comprise of a series of float system switches in a support assembly, mounted on the side of the filter tank in a convenient place.
The float switches will control a solenoid valve mounted in the intake pipework at a suitable point on the filter, to which the customer will connect a mains water supply.
A quick fill connection point can also be fitted.
The water supply can also control a neat oil supply dosing system, this unit will meter oil directly into the supplied water via a mixer bowl, the percentage mix will be variable.
Media Rewinding.
The spent media can be rewound and made ready for disposal by incorporating our optional rewinder.
Electrics
The electrical control panel for the system will be controlled by PLC unit from the range, specified by the end user, the panel will house all control equipment, starters, transformers, etc., for the filter system, system pumps, controls for levels & make-up, vacuum control switch, etc.
Guarantee
Any RBE Filter Installation would be fully guaranteed for a period of twelve months from date of commissioning.