Gas welding equipment. Oxygen/fuel gas blowpipes (cutting machine type) of cylindrical barrel. Type of construction, general specifications, test methods

2015 ◽  
Keyword(s):  
Test Methods ◽  
Fuel Gas ◽  
Welding Equipment ◽  
Machine Type ◽  
Cutting Machine ◽  
Oxygen Fuel

High Temperature Erosion Properties of Thermal Barrier Coatings Produced by Acetylene Sprayed High Velocity Oxygen Fuel Process

2000 ◽  
Author(s):  
M.A. Cole ◽  
R. Walker
Keyword(s):  
High Temperature ◽  
Thermal Barrier Coatings ◽  
High Velocity ◽  
Thermal Barrier ◽  
High Velocity Oxygen Fuel ◽  
Hvof Spraying ◽  
Powder Morphology ◽  
Fuel Gas ◽  
Barrier Coatings ◽  
Oxygen Fuel

Abstract Over the past 30 years, there has been considerable interest in the development of thermally sprayed thermal barrier coatings (TBCs) for aerospace and land based turbine applications. The use of TBCs enables higher operating temperatures, resulting in significant fuel efficiency savings. This paper reports on the development of dense Yttria Stabilised Zirconia (YSZ) thermal barrier coatings produced by High Velocity Oxygen Fuel (HVOF) spraying using acetylene as the fuel gas. The use of a high temperature gas erosion rig allowed the controlled evaluation of erodent size, velocity, impact angle, and temperature on coating performance. The work also covers the optimization of process parameters, including powder morphology, stand-off distance, oxygen to fuel ratio, gas pressures, and flowrates, and their effect on coating characteristics such as deposition efficiency, microhardness, and surface roughness.

Comparison of Structure and Wear Properties of Fine-Structured WC-CoCr Coatings Deposited by HVOF and HVAF Spraying Processes

2012 ◽  
Vol 188 ◽  
pp. 422-427 ◽  
Author(s):  
Iosif Hulka ◽  
Viorel Aurel Şerban ◽  
Kari Niemi ◽  
Petri Vuoristo ◽  
Johannes Wolf
Keyword(s):  
High Velocity ◽  
Wear Behaviour ◽  
Tungsten Carbides ◽  
X Ray Diffraction ◽  
Wear Properties ◽  
Fuel Gas ◽  
Cermet Powder ◽  
Pin On Disk ◽  
Oxygen Fuel ◽  
Disk Test

The aim of the work was to study the microstructure and wear properties of fine-structured HVOF and HVAF sprayed WC-10Co-4Cr coatings prepared from powder having submicron-sized tungsten carbides. The coatings were deposited by HVOF (High Velocity Oxygen Fuel) and HVAF (High Velocity Air Fuel) using propane as a fuel gas in both processes, and using oxygen or air as oxidizing gas for combustion, respectively. Nitrogen was used as carrier gas for the powder. Commercially available agglomerated and sintered cermet powder with main carbide sizes under 500 nm was used in this study. Scanning electron microscopy (SEM) and X-ray diffraction were performed in order to characterize the powder and the microstructures formed during the spraying processes. The microhardness HV0.3 of the coatings was investigated and the pin on disk test was used to determine the sliding wear behaviour. The rubber wheel abrasion test was performed in order to determine the abrasion wear resistance of the coatings.

Measuring the Flanks of a Bevel Gear Made by Heidenreich-Harbeck Cutting Machine

2012 ◽  
Vol 186 ◽  
pp. 163-168
Author(s):  
Faluvegi Erzsebet ◽  
Mate Csaba Zoltan ◽  
Cristea Luciana
Keyword(s):  
Mathematical Model ◽  
Coordinate Measuring Machine ◽  
Bevel Gear ◽  
Face Gear ◽  
Straight Bevel Gear ◽  
Machine Type ◽  
Cutting Machine ◽  
The Face ◽  
Measuring Machine ◽  
The Mathematical Model

This paper presents the mathematical model of the straight bevel gear flanks with octoid II teething which is measured with a coordinate measuring machine, type DEA Global Performance. The mathematical model is realized by theoretical equations which occur in the face gear. The experimental data, obtained by using the coordinate measuring machine, is analyzed and the compensation of the probe tip is calculated. The differences between the surfaces are determined.

Particle Behavior in a Powder-Laden HVOF Jet

2000 ◽  
Author(s):  
E. Lugscheider ◽  
C. Herbst-Dederichs ◽  
L. Zhao
Keyword(s):  
Particle Size ◽  
Supersonic Jet ◽  
Steel Powder ◽  
Limited Information ◽  
Fuel Gas ◽  
Particle Behavior ◽  
316 L Stainless Steel ◽  
On Line ◽  
Oxygen Fuel ◽  
Gas Ratio

Abstract The paper deals with an analysis of particle behavior in a HVOF-jet as a function of process parameters. The experiments were carried out using a commercial HVOF gun with hydrogen as fuel gas. A commercial 316 L stainless steel powder was used for spray material. The experiments were conducted by using on-line particle diagnostics in order to simultaneously detect particle velocity, temperature and diameter. The results were correlated with caught spray powder and splats. The experiments released that among many parameters the oxygen/fuel gas ratio is the most important parameter. It was found, that fragmentation of partially melted particles in a supersonic jet is not a neglectable phenomenon. It may cause excessive oxidation inflight and therefore is to be avoided in the production of oxygen-poor coatings. Furthermore, it was found that velocity or temperature measurements of particles have to be interpreted very carefully in order to characterize the process. Without taking a possible change of the particle size due to inflight fragmentation into consideration either measurement value will lead to very limited information benefit.

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