Rinse Water Controller as featured in the AWE Limited Summer 2015 Watermark
Rinse Water Controller
Back in the mists of time 70% of the plating in the United Kingdom was carried out within a 30 mile radius of Birmingham, cars came with chrome plated parts, and every instrument company had a rinse water controller in their product range.
With the decline of the plating industry most rinse water controllers have disappeared along with many of their manufacturers.
AS we are in our 33rd year, still with the original company name and original owners, we are able to supply the modern equivalent of the rinse water controllers with a large digital display and a 4-20mA output for data logging, PLC integration or a remote readout.
Our current C3645-RC rinse water control kit comprises of
- A conductivity controller powered either by a 230 or 115 VAC mains supply
- A dip conductivity cell in PVC for use in solutions up to 50°C.
- A brass solenoid valve able to close against zero pressure.
The solenoid valve being able to close against zero pressure is important. This means that the solenoid valve is suitable for use with mains water pressure and recycled or treated water feed to the rinse from a header tank.
The operation of the system is to install the sensor on the discharge from the rinse tank which should be located at the opposite end of the rinse tank to the clean water feed.
When work is rinsed in the rinse water tank the dragout from the previous process tank increases the conductivity. This is sensed by the conductivity controller which switches on the solenoid valve to add clean water.
The contents of the rinse water tank is now diluted, thereby lowering the conductivity. The lower conductivity switches off the solenoid valve until the process is repeated.
This ensures that the wash off process isn't compromised by contaminated rinse water and that the water bill isn't too high, by only calling for fresh water only when it's required, resulting in an efficient system.
We are able to offer systems for towns water, recycled water and a system for demin water with a lower measuring range.
For hot demin rinse tanks which are popular in the aerospace industry as the work flash dries due to heat in the work, we are able to offer a high temperature cell with automatic temperature compensation (ATC).
The ATC corrects the conductivity reading so that it is corrected back to 25°C and a polypropylene solenoid valve with stainless steel trim.
Our Level Best - Liquid Level Electrodes
The liquid level control using dip type contacting electrodes is a product we have manufactured for years.
It is one of our simplest and lowest costing products, providing simple reliable control and alarm for conducting liquids used in safe area, i.e. not an EX area where the risk of explosion may be present.
We have recently added a new multi-electrode holder, the LE8 to our conducting level electrodes system.
The LE8 multi level electrode holder
The LE8 Level electrode holder is manufactured in red PVC. The electrode holder is able to hold up to 5 off 1/4"Ø stainless steel, titanium, or hastelloy level electrodes. These can be manufactured up to 3 metres long in stainless steel or 2 metres long in Titanium or Hastelloy.
To prevent any possibility of tracking between the electrodes, the electrodes can be plastic coated with just the last 25mm of the metal exposed. To special order - the electrodes can be fitted with the connected cable sealed and potted for use in damp or steamy environments.
Liquid level electrode holder the ALC1101 can be set for high or low level control
The LE8 can hold up to 5 electrodes. Typical applications for 5 electrodes are level control using duty and assist pimps with a common earth electrode, and custom start and stop levels for the two pumps - this requires 2 x ALC1101 level controllers, one for each pump
Single pump control with both high and low level alarms positions this requires 3 x ALC1101 level controllers, one for the pump and one for each of the high and low level alarms.
The Grapevine - Hot Castings
We recently helped a customer with two very large heated processing tanks who was having problems with his insurance company.
They were nervous of the tanks over-heating. The heating was by hastelloy steam coils, fitted into the process tanks. The reagent was very corrosive acid and stainless steel temperature sensors were not lasting very long.
Their failing was resulting in the over heating of the vessel. The insurance company demanded some additional protection to be fitted to the process vessels.
We designed and built a very simple conventional polycarbonate panel with two temperature controllers for each tank.
Each temperature controller had it's own temperature sensor; our type TPA-2N-PTFE-1200 made of 316 stainless steel with a PTFE outer sheath and a PVDF boss with ABS connecting head.
Each controller operated it's own steam valve and each controller had its own high alarm set at 5°C above the control point which was also wired as a policeman to close both of the control valves.
To overcome any problems caused if the temperature sensor failed or the cable became damaged, the temperature sensor failed or the cable became damaged, the temperature controller used had an upscale burn out setting which means the temperature readings go high in a fault condition closing the steam valve.
The panel was designed so that both steam valves close if either controller reads 'high' for any reason.
This also triggered the audible and visual alarm system to warn the operator of a problem. This could also be used to initiate an auto-dialler with a SIM card to call a mobile phone or send an SMS message for an out of hours alarm.
If you require more information on the custom control panels for your process then please contact our sales office by calling 01785 254 597.
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