The new automatic screen washer RotorWasher-RW from Bochonow®
Specific requirements of the industrial screen printing, especially with possible new pastes, adhesives, insulating pastes, etc., ie the partial coating of the screen printing process, led to the development of RotorWasher-RW.
The stringent requirements of the ATEX guidelines of the EU (ATEX Directive 94/9/EC) were considered consistent with the design of the RotorWasher-RW.
Speziell angeordnete Flachstrahldüsen waschen in der RotorWaschanlage RW mit rotierenden Düsenstöcken die vertikal positionierten Siebdruckformen von beiden Seiten.
Specially arranged flat spray nozzles are washing in the RotorWasher-RW with rotary spray bars vertically positioned screen printing forms from both sides. The washing process follows the proven "high-volume" principle of BOCHONOW®. It provides a nozzle diameter of more than three millimeters (!) for optimum cleaning efficiency, extremely short washing times, and low-maintenance operation.
The bilaterally arranged spraybars have a type test according to the ATEX directive
EC-Type Examination Certificate no.
IBExU U03ATEX1047X
The solvent is conveyed with a powerful electric centrifugal pump of a large tank under the wash chamber into the circulation.
The high flow rate oft he pump allows the use of clog resistant nozzles with large diameters and high cleaning efficiency.
Screen cleaner as a cleaning medium is used with a flash point >55°C and a conductivity of >10-9 S/m..
The large-capacity solvent tank made of high grade stainless steel 1.4301 has an easily accessible and removeable filter cartridge.
As standard, the holding device for the optional drum pump is already provided.
Optionally a drum pump with stainless steel pump tube is available.
The exhaust pump tube is inserted through the stable holding device into the pump sump of the washing tank. Thus, a possible residue-free emptying of the tank is possible.
To refill fresh solvent, the drum pumpe can be used also.
The optional drum pump can be used for the residue-free emptying AND refilling of the washing tank.
To barrel grounding a corresponding earth clip with stainless steel cable is standard.
A key part of the user-friendly features is the fuel indicator. A float is integrated in the tank containing a visual level indicator, thereby guaranteeing safe and reliable signals of the recent amount of solvent in the washing tank.
Control of the remaining amount of solvent is available at a glance.
Here is the wash tank with enclosed filter cover, the holding device for the drum pump (option) and the visual level indicator (on max. filling volume).
It can display the maximum and minimum solvent level.
According to the ATEX directive the exhaust fan was designed to ATEX Category 3. The exhaust fan is installed on the air control box and the exhaust air volume ratios between the drying chamber and the door exhaust system of the washing chamber can be adjusted continuously.
Powerful exhaust fan accoring category 3 of ATEX.
Flange dimensions for connection to the existing exhaust 125 x 130 mm.
II2GcT3 PTB02ATEX3173
Protect the environment and save valuable resources are the foundation of the VOC directive, which is implemented in the new BGI 801.
To meet these demands the exhaust system of the washing chamber is prescribed as a door exhaust system. This requirement is included in the construction of RotorWasher-RW.
The exhaust system constantly extract from the air duct, which is designed around of the loading door.
If the loading door opens, any escaping solvent vapors are immediately removed and kept away from the user.
The drawback of the high solvent emissions by the formerly used chamber extraction systems is passive.
Unique door exhaust system to save solvents and compliance with the requirements of the VOC Directive and the BGI 801.
The exhausted air quantity is adjusted at the air control box to the individual circumstances.
Decisive factor for the cleaning effect of the RotorWasher-RW the amount of solvent which is sprayed onto the screen per time unit.
In the used nozzle diameter of 3 mm, a substantial amount of screen cleaning solvent is circulated. Even the smallest model of the RotorWasher-RW the solvent pump provides 10,000 liters per hour. This low-noise solvent pump is performed on all wetted parts in stainless steel 1.4404. As sealing material exclusively high-quality KALREZ® is used.
For high demands the optional fine filter with stainless steel case and replaceable filter cartridge (25…200 microns) is used on the pressure side of the solvent pump.
We developed a fast venting of the solvent pump. This ensures trouble-free operation of the plant. Even after long periods of empty sequences the system bleeds automatically without manual work!
Powerful centrifugal pump from German production.
Wetted parts of stainless steel 1.4404, Kalrez® seals from the highest quality.
On the photo, the stainless steel filter and the standard fast venting device is seen.
Reliability and availability of systems are the challenges for modern equipment manufacturer.
The suction and discharge piping of RotorWasher-RW was performed in seal-less cutting ring technology.
The enormous flow of the wash pump was respected with the choice of the nominal diameter of 28 mm.
All piping oft he suction side and the pressure side are made of seal-less cutting ring technology.
Thus, the high reliability and availability is ensured.
The earting of all piping is guaranteed by the cutting ring technology.
Particular attention was paid on the construction of the screen holding frame of the RotorWasher-RW.
The inclined suspension is perfect for fast draining and drip-off oft he solvents. The screen holding frame can be executed (as seen in the figure) also for loading a multiple number of smaller screen frames.
The screen holding frame is provided with a continous drip pan, which is brushed off by pulling out the frame. This unique design prevent spillage on the front operator area, while the front entrance to the plant is completely free, because there is no need for a very disruptive, permanent collection device.
Through the pull-drip pan below the screen holding frame the solvent will not drip in the front operator area!
The screen holding frame can be executed (as seen in the figure) also for loading a multiple number of smaller screen frames.
After the drip-off time, the still solvent wet screen frames will be removed from the washing chamber and placed in the drying chamber.
As standard, the drying chamber is equiped with 4 slots for the max. screen frame size. On customers demand, it is also possible to equip the drying chamber for several smaller screens (see figure).
The drying chamber is continuosly vented with a large amount of air and ensures rapid drying of the washed screen frame.
Because of the sepparated drying chamber, large quantities of solvent can be saved, since the drying process is carried out not inside of the washing chamber. Thus, the washing chamber is not dried out!.
Another important advantage of the separately designed drying chamber is an enormous increase of throughput of screens. During the wet screen is dried in the drying chamber, additional screen(s) can be washed in the washing chamber simultaneously. Two processes running parallel to save time!
The separate drying chamber hold up to 4 screens of max. size. On customers demand, it is also possible to equip the drying chamber for several smaller screens (see figure).
- The separate drying chamber saves solvent, since the wash chamber is not dried out!
- The separate drying chamber accelerates the whole process, since it can be dried and washed simultaneously.
The newly designed door-locking system offers optimal user protection.
The easy to use latch system is scanned electronically and triggers the pneumatic door locking mechanism. This ensures, that start of the washing process can be done only with firmly closed door.
The pneumatic door lock prevents opening of the loading door during the washing and drip-off process.
Easy-to-use door locks with double ledger.
The pneumatic door lock prevents from starting the process without frimly closed loading door and opening of the loading door during the washing and drip-off process.
The solvent tank is monitored by several devices. Besides the optical tank capacity control (see above) a stainless steel float EX-switch is integrated to protect the pump from running dry.
A EX-proofed stainless steel temperature sensor monitors the bath temperature and the system switches in disorder at a solvent temperature >40°C.
The monitoring devices in the solvent tank, carried out in stainless steel:
- Float switch for dry run protection of the washing pump
- Temperature sensor for monitoring the maximum permissible solvent temperature of 40°C.
The stainless steel control cabinet is located on the rear oft he system and is ready to connect.
Via the digital programming display on the front panel of the control cabinet, the washing and drip-off time can be individually programmed.
The stainless steel control cabinet at the rear of the system.
Programming of the washing and drip-off on the digital display.
As standard, the RotorWasher-RW comes with a drip-pan. The whole screen washer is in a pan made of high-grade stainless steel with 2 mm thickness, which is fitted with grids in the front area. The grids could be removed easily for cleaning
Drip-pan made of high-grade stainless steel 1.4301.
According to the guide lines for drip-pans, it is made from sheet thickness of 2 mm and a height of min. 50mm.
Galvanized grid provide the user with a non-slip, safe footing!
The loading door seal the washing chamber reliably during the washing process with a special technique!
The outer door is pressed into a completely solvent-resistant door gasket. The spring mounted interior door is being pressed against the inner doorframe while closing the loading door.
This double structure design allows for wear-free and secure seal.
Loading door designe das a double door.
- Exterior door with solvent-resistant sealing
- Spring loaded interior door with stanless steel doorframe
The RotorWasher-RW is made of diamond-patterned, high-grade stainless steel. This material is very strong (about 2 mm thick) and is characterized by a highly scratch-resistant and visually appealing surface.
The base is made of extremely stable square objects and can be disassembled for transport!
The RotorWasher-RW is manufactured on the most modern CNC laser cutting machines.
Integrated manufacturing systems allow us to create complex metal structures.
The diamond-patterned sheet is stylish, very stable and robust, so that the optics of the system is guaranteed for many years.