METALLIC POWDER BONDING PROCESS
The newest metallic powder coating bonding process
Powder coatings Bonding process, also called thermal Bonding technology, is under a certain temperature, the metallic pigments adhesion on powder coating particles, create a coating of metallic effect. Traditional bonding mixer is the use of plastic industry for some improvement high mixing equipment, temperature control by friction heating way, short of good binding effect, this paper introduces a new bonding process where special design and intelligent temperature control device can mix for a long time under 65-70 ℃ without caking, it provides very good binding effect.
Advantages for bonding process in metallic powder coating
1. Developing brand-new environmental coatings
Nowadays environmental requirement is no longer a concept and sense, but a regulation and compulsion. The VOC paints with liquid metal effect will be gradually eliminated from market, and the bonding powder coatings complying with environmental requirement and exhibiting metal effect will play an important role of substitution in this transformation. In the bonding powder coatings the content of metallic pigment can be increased to 10% or higher, and the coating effect can completely rival the liquid paints. One who is the first to master this bonding process and technology is the winner in this transformation.
2. Eliminating quality problems of coatings
The bonding process can eliminate the following quality problems existing in conventional dry mixing process:
Problems in coating: poor leveling
Existence of sand
Existence of chromatic aberration
Liable to discolor
Problems in spraying: poor powder absorption
Liable to burn out spray gun
Useless recovery powder
3. Reducing cost of production
For metal coatings with the same effect, the metallic pigment in ingredient with bonding process can be approximate 10%~20% lower than that with conventional dry mixing process, enabling reduction of the cost of ingredient. With adoption of bonding process, recovery powder can be reused so as to save resources and reduce wastes.
In spraying the rate of finished products is increased so as to reduce spraying expenses.
Thanks to environmental coating, high amount of environment related costs are not required in production and application.
II Traditional bonding mixer of powder coating is the use of plastic industry high mixing equipment, some improvement on friction heat production, temperature rise to about 50 ℃ immediately feeding. This technology has some disadvantages
1. It is difficult to control in production process, often produces a subscription fee
2. Because the temperature is not enough, metallic pigment adhesive effect is poor
3. Bonding mixing time is not enough, not fully mixed with adhesive
4. There is a big quality difference between production batches
5.It can't produce high flash coatings because the metal paint is damaged by high speed friction heating process, ,
6.Metallic pigment were broken and caused metallic pigment dosage increased
III A new state on bonding process
In 2011, we launched a new bonding process which can make the powder coating materials in higher temperature (65-70 ℃) for a long time (3-5 minutes) mixing through to the equipment of special design and intelligent temperature control technology. It has the following advantages.
1.The bonding process is conducted at constant torque and shear force so as to avoid damage of high shear force to metallic flake pigment in conventional bonding machines
2.The bonding effect is very good by high temperature long time mixing
3.The entire process by the computer intelligent control
4.Material temperature can be controlled precisely during bonding
5.Material sticking will not happen during production..
6.Product batch quality stability
7.The bonding system takes automation of production process into full account.
IV Features for this process
1．Effectiveness of bonding
Really effective bonding process is embodied in uniform mixing between basic material and metal pigment above Tg point for long time. The Wisdome bonding system can guarantee bonding mix of general powder coatings for 3-5min without caking at 65℃-70℃ to as to achieve real bonding effect, and this is absolutely benefited from its professional design and precise control.
A． Inner wall, lid and discharge of the bonding machine are made of special steel, which is mirror polished after special treatment, so material sticking will not happen during production..
B．The distance between mixing tools and container wall is especially specified to T avoid dead spaces in mixing area..
C．The mixing tools are designed into unique multi-layer structure, and the angles and motion curves of mixing tool on each layer are different. Moreover the mixing tools have self-cleaning feature so as to guarantee uniform mixing of all materials.
D．The deflector is installed through the container lid and is adjustable in angle to guarantee the optimized flow of material.
E．Intelligent temperature control system enables precise control of material temperature during bonding process.
2．Intelligence of process
The whole process is under intelligent judgment and control of computer system, as a result, material temperature can be controlled precisely during bonding. Moreover, the bonding process is
conducted at constant torque and shear force so as to avoid damage of high shear force to metallic flake pigment in conventional bonding machines， therefore, coatings with high-flash effect can be produced.
3．Reliability of equipment
In Wisdome bonding system the driving system adopts German SIEMENS motor and SIEMENSfrequency converter, the control system adopts SIEMENS PLC and SIEMENS touch screen, low-voltage electric appliances are from Schneider, and pneumatic system is from Taiwan ARTIC.The whole configuration and reasonable design guarantee reliability and safety of the system.
4．Safety of production
A．During running of the whole system, oxygen monitoring and nitrogen protecting systems prevent the risk of dust explosion.
B．All mechanical parts should be grounded reliably to guide away generated static immediately. C．At running and connecting parts of machinery sensors and interlocking mechanisms are set to guarantee reliability of connection and safety of operation.
5．Simplicity of operation
The Wisdome bonding system takes automation of production process and simplicity of operation
process into full account.
A.The system can save various production process parameters of products for real-time callout to perform production, or can be networked with PC for centralized control and management.
B. The whole operation is fulfilled just by one key, and nitrogen detection, heating up, bonding, cooling and feeding processes are carried out automatically without operations by personnel.
C. Production modes are divided into manual mode, trial production and mass production mode with convenience for trial and production
D. The discharge is designed in swing-way, easy to clean machine change type.
V Technical data
三．TYPE HM350/KM1200 HM200/KM800 HM10
HM volume 350L 200L 10L
KM volume 1200L 800L ——
Batch loading capacity 100KG 60KG 3KG
Production per hour 400KG 240KG ——
Operating voltage 380V，50HZ 380V ，50HZ 380V ，50HZ
Motor drive way frequency
Control mode PLC PLC PLC
Temperature sensor PT100 PT100 PT100
Water connections R2” R1” R1/2”
R1/4” R1/4” R1/4”
Air pressure 0.4-0.6MP 0.4-0.6MP 0.4-0.6MP
Paint color RAL9010