SprayCamTM is Control Vision Inc's new imaging and diagnostic system specifically targeted for the Thermal Spray industry. SprayCam is designed to be a low cost, low maintenance, easy to use and robust system for viewing and measuring particle injection distributions and velocities for Thermal Spray Processes, ensuring Reliable and Consistent Coatings.
Key Features:
- Images Particle Diameters >20um
- Images Particle Velocities <500m/s
- Two mounting configurations: Torch Mount for continuous process monitoring or Booth Mount so the process can be checked at intervals throughout the process
- Velocity Measurement available
- Software automatically detects particle distributions and densities and alerts an operator if the process is outside of set parameters.
Benefits:
- Up to a 50% reduction in Coating Variation (Ref 1) with proper Injection Optimization and "Sweet Spot" Tracking (see below).
- Consistent and Reliable Coatings can be applied day after day despite minor changes in spray process parameters.
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Real-time, computer assisted operator feedback on particle injection and feed consistency allows for increased efficiency and reduced process variability.
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Reduced booth downtime by establishing process baselines and allowing operators to see and adjust torch problems in real time.
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Reduced overall time to change or establish new process parameters.
Injection Optimization and "Sweet Spot" Tracking:
Recent research (Ref 1 and 2) has demonstrated that an optimum particle trajectory exists which will ensure maximum energy transfer to injected particles regardless of Primary and Secondary Gas Flow Rates, Particle Shape and Sizes, Particle Injection Angles, and Particle Feed Rates. At this trajectory "Sweet Spot", particle temperature and velocity are optimized, deposition efficiency will be maximized, and coating variability is at a minimum. This "Sweet Spot" can be maintained using only one parameter: Carrier Gas Flow Rate. Once this "Sweet Spot" is found by optimizing Deposition Efficiency using the Carrier Gas Flow Rate, SprayCam will remember its position and limits can easily be set. Before, during, and after the thermal spray process, SprayCam can be quickly used to ensure the consistency and reliability of your process by locating the particle distribution and alerting an operator if it falls outside of the "Sweet Spot" limits. If this occurs, the operator simply makes a few adjustments to the Carrier Gas Flow Rate to adjust the trajectory of the particles, bringing them back into the "Sweet Spot" and ensuring a consistent coating.
Application Example:
A new lot of powder is received which has a slightly different size distribution than what is typically sprayed. This will cause the particles to have a different trajectory in the plasma, resulting in variability in the coating. SprayCam will test the particle distribution to ensure it is within the established set limits prior to spraying the component. If the distribution falls outside of the "Sweet Spot", SprayCam will alert the operator who can then adjust the Carrier Gas Flow Rate until the proper particle trajectory is obtained. Once this has been done, the operator can spray the component with confidence that the new lot of powder won't affect the coating being sprayed.
References:
1. V. Srinivasan, A. Vaidya, T. Streibl, M. Friis, and S. Sampath, "On the Reproducibility of Air Plasma Spray Process and Control of Particle State", J. Thermal Spray Technology, 2006, 15:739-743.
2. V. Srinivasan, M. Friis, A. Vaidya, T. Streibl, S. Sampath, "Particle Injection in Direct Current Air Plasma Spray: Salient Observations and Optimization Strategies", Plasma Chem Plasma Process, 2007, 27:609-623.
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