Process Solutions for Candle Wax
Application Case Study – Wax Dispensing for Candles
Valves Online were approached by a customer who had experienced numerous issues with their existing set-up for dispensing the wax for candles into the glass containers. Their existing set-up consisted of Burkert type 0255 solenoid valves. These presented numerous problems to the customer:
- Failure to operate due to solidified wax in the mechanism
- Coils burning out due to solidified wax
- Corrosion on brass bodies
- Heating required to prevent wax solidifying during operation
- Low flows caused long dispense times and reduced product efficiency
The customer was keen to replace the system with a product that would eliminate these issues from their system and offer improved longevity, operability and performance.
Using a solenoid valve was not really an option thanks to the flows required, the temperature, chemical compatibility, and physical properties of the media.
The candle wax consisted of a paraffin base which was not compatible with EPDM and the colourants and scents that were to be used with it meant that NBR would also not be suitable, leaving us with the options of PTFE or FKM for widely available seal materials.
To allow it to flow the way required trace heating on the pipelines and valves and further components, however when the factory was shutdown overnight and weekends the way would solidify in the line and valve often blocking the small orifices and flow paths in the solenoids that had been used over the years.
After consultation with the customer it was agreed that a pneumatically operated valve would provide them with the speed of response required by the process, by using the pneumatic valves coupled with a pilot solenoid valve the existing control system could be utilised requiring no reprogramming of the PLC or large scale rewiring effort.
Burkert Type 2031 General Purpose Piston Operated Diaphragm Valve
Valves Online supplied the Burkert Type 2031 General Purpose Piston operated diaphragm valve, this offered many benefits in a cost-effective package including:
- Separation of the medium from the operating mechanism, thereby reducing the clogging by solidified wax and preventing the valves from failing to operate
- Pneumatic operation combined with the hermetic separation of the operator meant that the issue of coils burning out was removed from the process, reducing costs and increasing machine up-time
- PTFE Diaphragms allowing full compatibility with the media and cost effective simple to effect spares program
- Flow optimized body design, improving the flow capacity over the previously installed solenoids increasing process speed and efficiency of the process
- The self-draining design (when installed as per recommendations) also meant that the clogging issue was largely removed.
- Stainless Steel Body Construction meant that the corrosion from the chemicals used for the colouring and scent was eliminated. This had the knock-on effect of removing discolouration from the end product and reducing the volume of colourant required, reducing process costs.
- The self-draining design coupled with the operation of a diaphragm did not result in the removal of heating the valve to prevent solidification however it did reduce the amount required thanks to the amount of body material.
We combined the Type 2031 with the Type 6012P Banjo mount solenoid valve. The solenoid mounts directly to the Type 2031, and makes use of a 6mm Push-fit Pneumatic Connection making fa a very compact valve in comparison to offer technologies such as Ball Valves or Pinch Valves.
As a further note the use of the diaphragm valves has enabled the customer to look at removing the electric line heating and is now looking at making use of jacketed pipework and heating pots on the valves to make use of a steam/hotwater line heating system them with the aim of reducing the electricity bill and making use of the existing steam capacity that is currently going to waste i.e condensate/flash steam recovery.
For more information or to discuss your Valve requirements, please do not hesitate to get in contact with our Technical Team at Valves Online by telephone on 01822 855 600 / 0161 480 5700 or by email on firstname.lastname@example.org