Engine regeneration is an exact science that includes many technical variables. The technology has evolved as the engines have become more advanced. In recent years, fuel efficiency and emissions control have changed how diesel engines have been developed and, therefore, restored. In many cases, older models with lower fuel consumption are now being upgraded to improve functionality. Often, the engine is more powerful than the day when it initially left the factory 20 years before.
Recently, Ford Motor Company has implemented advanced recovery technology aimed at providing new life for engines that would otherwise be disposed of at a cost. Traditionally, when car engines fail, they are simply removed from the frame and replaced, because restoration methods can be costly for the consumer due to simply replacing the engine. A crack in the cylinder block or cylinder head usually meant one of two repairs: cold plug and seam welding or a costly and laborious process called hot welding, where the entire block heats up to 1400 degrees Fahrenheit, making furnace welding and then allowing the whole block cool evenly in the sand pit for 3-5 days. Hot welding is more efficient than cold seam welding, since the entire metal surface is structurally exposed to heat, and therefore not exposed to weakness around the repaired crack.
The new Ford process adopted is called the Plasma Transferred Wire Arc. Unlike traditional plasma plasma welding processes, the new technology applies a thermal spray inside a cracked or faulty engine block that is molecularly coupled to divisors in a metal structure. The surface of the block or cylinder head is properly sharpened to correct OEM specifications in the range of 0.001 inch.
How plasma arc welding works
As a rule, cast iron parts, special welding and complex machining processes are required to restore the block. Plasma wire arc technology works using traditional coating wire that is subjected to high pressure from the sprayed gas mixed with plasma gas surrounded by a cathode. The cathode is heated electronically through an arc of wire, and the combination of both gases is forced out through
and is jetted out of particles evenly over the surface of the cylinder block.
Plasma wire arc (PTWA) differs from traditional plasma arc welding methods, which are known as wire arc welding (WASW). PTWA uses only one wire for a metal substance (raw material), where WASW rests on two metal wires that are independently fed to the sprayer. Charged wires create an arc, and the heat of the two wires melts to form molten material, which is supplied with air to fill the weld. When welding PTO, the melted particles then instantly collapse due to their high kinetic energy, then solidify on contact with the formation of crystalline and amorphous phases. With PTWA technology, plasma gas usually contains a greater amount of nickel, which produces a gel-like substance that binds tightly to cast iron or aluminum. It is possible to manufacture multilayer coatings with PTWA welding. The use of another substrate in the feedstock can lead to the formation of a base layer of particles that are primed for a secondary “sealing” layer of solid particles, which is joined over the first weld. This secondary coating provides a very durable coating. PTWA is commonly used in engine components, such as blocks, connecting rods, cylinder heads or bushings. With the help of wire with wire with wire or wire of metal alloy can be used in the raw materials or in the form of metal alloy powder. The most common powdered alloy to use is cobalt No. 6 with the addition of nickel for better adhesion on the substrate. In recent years, companies have decided to choose more for powerful raw materials, as it is 50% cheaper than traditional wire alloys.
The plasma generator or gun head consists of a tungsten cathode, an air-cooled pilot nozzle made of copper, conducting electricity, which is known as the anode. The head is mounted on a rotating spindle that rotates up to 600 rpm. The wire is fed perpendicular to the center of the nozzle. Plasma gas is introduced through tangential wells located in the cathode holder to ensure the creation of a vortex. The whole process from creating the arc to the filing of the weld in the substrate takes just 10,050 seconds.
Plasma Transmitted Arc Welding Vs. Traditional plasma arc welding
The advantages of plasma transferable arc welding compared to traditional plasma arc welding:
Plasma binding arc welding is a highly automated technology and can be reproduced and reproduced at large-scale production and production facilities. The software can scan and automatically repair cracks or weak points in cast iron or aluminum. Plasma transmission. Arc welding is simply a more accurate method of plasma arc welding. PTWA welding allows the metal powder to be loaded into the raw materials in detail. This reduces the amount of waste, and as a result, a significant amount of metal raw material is saved for future use. One of the greatest advantages of plasma-portable arc welding is the precise control of important welding parameters. With a PTWA direct current, you can adjust the voltage, power, gas feed rate, gas flow rate and heat supply with a high degree of replication and consistency from unit to unit in a production facility. By controlling the heat input, the welding operation can ensure that the dilution of the welds can be controlled by about 7% in most cases.
In addition to cost savings, PTWA simply produces a better weld than traditional welding or even traditional plasma arc welding. Plasma portable wire arc welding creates special alloy deposits that are harder and more resistant to corrosion than alloys used in tungsten arc welding or using oxygen welding. When welding with plasma wire with arc welding, deposits deposited on a substrate are classified as having very low levels of oxides, inclusions, and breaks. PTWA alloys are very smooth as a whole due to the fact that at the molecular level, welded joints correspond only to the substrate, and not to the surface of the cast iron.
This significantly reduces the amount of honing required after welding. Finally, the greatest advantage of plasma-borne portable arc-plasma welding is the flexibility that it offers for welding very precise cracks. Limits can be adjusted to provide plasma deposits from 1.0 mm to 2.6 mm or higher as needed. When welding plasma-portable arc welding, these small welds can be precisely deposited in one pass, taking into account the burning force and the powder used.
How plasma arc welding works
All the benefits of plasma welding are related to the energy generated by the plasma jet. The thermal energy outputs of the plasma jet are interdependent on the electrical input created by the cathode. The normal plasma welding arc welding temperature can be above 14,500 ° F - 45,000 ° F compared to a typical electric arc arc temperature of around 11,000 ° F. It is a common misconception that plasma arc welding varies from traditional electric welding, but all welding contains partially ionized plasma; the difference between them is that during plasma arc welding there is one compressed volumetric arc of the plasma.
During the welding of a flame plasma arc, a plasma arc is created when a negatively charged electrode comes into contact with a positively charged piece of metal. In more simplified terms, the arc is transferred from the cathode to the piece of metal being processed. The transit arc contains a high plasma jet velocity and high density.
The speed and speed of the arc make traditional plasma arc welding ideal for cutting and melting metallic materials where there is no oxy-acetylene torch. The speed is created by interrupting the circuit with a limiting resistor, which only allows a current of about 60 amperes. This breaking of the circuit creates a transmitted arc between the atomizer nozzle and the electrode, and a preliminary arc is established between the electrode and the nozzle. As soon as the preliminary arc touches the surface of the metal that is being welded, a current flows between the electrode and the surface of the metal, thus igniting the transmitted arc, which is basically a flammable powder. The final stage of ignition occurs when the pre-arc initiation unit is disconnected from the welded metal. The preliminary arc is extinguished as soon as the transmitted arc interacts between the electrode and the place of work of the metal. The most common metals that can be welded using plasma transferable arc welding are aluminum, copper, copper, nickel, inconel, monel, nickel, precious metal groups, low carbon steel, low resolution steel, medium and high carbon, stainless steel, alloy steel, titanium and tungsten. Metals that are not recommended for welding plasma-borne arc welding include bronze, cast, small, nodal, forged, lead, and magnesium alloys.
New technologies of plasma arc welding
Other types of welding that are developed or used by large automakers:
Plasma Rota: This plasma arc welding process was created by Sulzer Metco and consists of a rotating powder aerosol plasma jet system. This technology is currently used by Volkswagen.
Double arc wire: This is the most common and cost-effective use of plasma arc welding, consisting of two rotating wires. This technology was developed by AMG Corporation and is used at Daimler AG.
High speed oxygen fuelA: General Motors has developed high-speed oxygen-burning systems that contain more oxygen in the plasma substrate. This system also uses the traditional single-core feed system.
Plasma Transferred Wire Arc was invented in 2009 by Flame Spray Industries and improved by Ford Motor Company. In fact, Plasma Transferred Wire Arc Welding won the 2009 IPO National Inventor of the Year award. PTWA technology is currently used by Nissan in the Nissan GTR, Ford Mustang GT500, and Caterpillar in heavy engine recycling.
Ford representatives said that the technology provides a 50% reduction in CO2 emissions when comparing the cost of production of a new engine. The use of recycled materials requires less downtime for the customer and reduces production costs. It will be interesting to see how precision welding turns out, as technology continues to improve efficiency, durability and cost reduction in the coming years.
