NATIONAL THERMOSPRAY, INC.
NATIONAL THERMOSPRAY, INC.
COATING SOLUTIONS ....
METALLIZING PROCESS
PROJECTS OF INTEREST
HYDROELECTRIC US ARMY CORPS USACERL REPORT ON HVOF
We have a full line of services from High-Velocity Oxygen Fuel Systems, HVOF, and Plasma Coatings, Metallizing which includes combustion wire and combustion powder guns and dual-arc System, and a state-of-the-art mobile hvof field unit. For easy reference we are also at www.hvof.com. We would like to introduce your company to an extremely versatile industry, that offers an unlimited range of possibilities to industries with extreme corrosion and wear environments. National Thermospray has coating solutions for the turbine industry, chemical and refinery industry, to agriculture, marine, hydroelectric plants, pumps to paper mills. If your company needs to maximize the life of your present or future equipment, maybe the answer to your particular problems. We have all the personnel to handle your coating needs. National Thermospray, Inc. can perform the following services listed below:
Onsite Machining
Spray Units
HVOF
Plasma
Dual Arc
Powder
Combustion Wire
Rokide
National Thermospray, Inc., would like to introduce your company to a recently new field process called High-Velocity Oxygen Fuel (HVOF) thermal spray service. The desirable properties of HVOF process is High Density and even to a Negligible Porosity, resulting from high spray-particle velocities produced by a hot, combustion-driven, high-speed gas jet. Although HVOF spray process represents a new coating technology, in principle, it amounts to a small rocket engine. The HVOF system has revolutionized the thermal spray industry. HVOF is a supersonic process which delivers well over 7000 fps of velocity and can exceed bond strengths of 12,000 psi. It is an extremely versatile system that offers an unlimited range of possibilities to industries with extreme corrosion and wear environments such as chemical and refinery, agriculture, marine, power plants, pulp and paper mills. If you need to maximize the life of your present or future equipment, than HVOF maybe the answer to your particular problems. HVOF coatings is emerging as one of the most cost effective ways to combat wear and corrosion. National Thermospray, Inc. offers a turnkey field process with state of the art techniques, which includes robotics and experience, that can save your company time and money. We hope the following technical information will significantly change the way you look at saving and protecting your equipment in the near future. If you have any questions or need further information about this service, please contact us.
Basic Principles of Operations: The HVOF unit uses an oxygen-fuel mixture consisting of propylene, propane, or hydrogen, depending on users coating requirements, to produce the highest quality coatings. Fuel gases are mixed in a proprietary siphon system in the front portion of the HVOF gun. The thoroughly mixed gases are ejected from the nozzle and ignited externally to the gun. Ignited gases form a circular flame configuration which surrounds the powdered material as it flows through the gun. Combustion temperature is between 5000º F to 6000º F depending on fuel. The circular flame shapes the powder stream to provide uniform heating, melting, and acceleration . Pre-selected oxygen, fuel and air values are specified for each material to optimize dwell time in the flame.
Typical Coating Properties: The key success of HVOF is the extremely High Kinetic Energy that is being produced and transferred between the HVOF unit and the substrate using space-age rocket propulsion technology. Typical velocities approach 5000 fps to over 7200 fps depending on which hardware is selected. With both thermal and kinetic energy, the high velocity particles are embedded into the substrate to form a superior coating with the following characteristics:
High Density
The coatings produced though HVOF develop very high densities because of the high kinetic energy associated with this process.
High Bond Strengths
The bond strength of these coatings are typically higher because of particle velocities. Bond strengths of tungsten carbide/cobalt series tested in accordance with ASTM C633-76 procedures, for example, typically show values exceeding bond strength of the adhesive at 12,000 psi.> Zero or Negligible Porosity(with no interconnecting porosity)
THESE BEND TEST SHOW HIGH STRUCTURAL INTEGRITY OF
HVOF COATINGS APPLIED OVER CARBON STEEL
Zero or Negligible Porosity (with no interconnecting porosity)
Metal Working Capabilities
Essentially Stress Free
Greater Hardness
Greater Thickness
Low Thermal Input (Substrate temperature less than 300º degrees F which insures original mechanical properties and with No Stress Relieving Required)
National Thermospray, Inc. has a wide variety of materials that can be applied in the field to protect surfaces from destructive environments, such as Hydrogen induced cracking and corrosion from H2S, Sulfuric and Nitric acids, Carbonic and Hydrochloric acids and many others. NTI uses the highest quality powders that are specifically sized to permit optimized melting when introduced to the HVOF gun. The following list of materials are commonly used:
Monel
Tungsten Carbide
National Thermospray, Inc. has a state-of-the-art mobile field unit. NTI has all the personnel to handle your coating needs. The HVOF unit is trailer mounted and has the capabilities to apply a coating 250 feet from trailer without any modifications. This controls the contaminants since the unit and spray materials are stored and secured in the trailer and only the gun is in the work area. We put safety first. NTI has an excellent safety record and we operate under OSHA 1910 FEDERAL SAFETY REGULATIONS.
Since the majority of NTI work is in confined spaces, the company has gone to great lengths to protect employees by using robotics and installing cameras in the work areas to monitor work conditions at all times. NTI has also incorporated all emergency shut-off systems into the HVOF System so the spray technician in the confined space and the unit technician at the camera monitor have control over the system in case of an accident or a plant emergency.
Hastelloy® is a registered trademark of Haynes International Inc.
Stellite® is a registered trademark of Deloro Stellite Co Inc.
Inconel® and Monel® and Incoloy® is a registered trademark of INCO (International Nickel Co)
NATIONAL THERMOSPRAY, INC.
5120 Oak Ave.
Pasadena, Texas 77503
OFFICE: 281-373-0609 or 281-991-1133
CELL 713-898-6844 (24/7)
FAX: 281-991-9911