Atomizer Oil Separator Tube Titanium Alloy Lost-wax Casting

* Titanium alloys possess excellent corrosion resistance. For atomizer separator tubes, this effectively resists chemical corrosion when in contact with various atomizing liquids, ensuring long-term performance and extending service life. For example, in atomizing liquids containing acidic or alkaline components, ordinary metal materials may corrode quickly, while titanium alloys remain stable.

* Titanium alloys have high strength and are lightweight. Separator tubes require a certain structural strength to ensure their stability and safety within the atomizer. The high strength of titanium alloys meets this requirement, while their relatively light weight does not add excessive burden to the overall atomizer design, facilitating miniaturization and portability.

* Lost-wafer casting can manufacture high-precision parts. Atomizer separator tubes typically have complex internal structures and precise dimensional requirements. Lost-wafer casting can accurately replicate the shape of the mold, ensuring the dimensional accuracy and surface quality of the separator tube. For example, the inner diameter and wall thickness of the oil separator can be strictly controlled within the design requirements, ensuring good fit with other components of the atomizer.

* This process can manufacture parts with complex shapes. Oil separators may need to be designed with special shapes to achieve better atomization or integration with other components. Lost-wax casting is not limited by traditional machining methods and can manufacture various complex geometries, such as oil separators with curved channels or irregularly shaped ports.

* Lost-wax casting produces a good surface finish. A good surface finish reduces the residue and adsorption of atomized liquid on the inner wall of the oil separator, which is beneficial for improving atomization efficiency and quality, and also facilitates cleaning and maintenance.

First, based on the design drawings of the atomizer oil separator, a 3D model is created using computer-aided design (CAD) software. Then, a master mold is made using rapid prototyping technology (such as 3D printing) or traditional machining methods. The accuracy and quality of the master mold directly affect the quality of subsequent castings; therefore, its dimensional accuracy and surface roughness must be strictly controlled.

Molten wax is poured into the master mold. After the wax cools and solidifies, the wax model is removed from the master mold. The shape and size of the wax model should match the final oil separator casting. To improve production efficiency, multiple wax models are usually made and combined into a wax model assembly, connected together by a gating system and risers.

The wax model assembly is immersed in a special refractory coating, ensuring a uniform coating layer on the surface. A layer of refractory sand is then sprinkled onto the coating surface, allowing it to adhere firmly. This process is repeated several times to form a shell of a certain thickness. The strength and permeability of the shell are crucial to the quality of the casting; therefore, appropriate refractory materials and coating formulations must be selected based on the characteristics of the titanium alloy and the casting process requirements.

The wax model assembly with the shell is placed in a steam dewaxing furnace or hot water, causing the wax to melt and flow out of the shell. To ensure complete wax removal, the dewaxing temperature and time must be carefully controlled. After dewaxing, a cavity with the same shape as the oil separator is formed inside the mold shell.

The dewaxed mold shell is placed in a high-temperature firing furnace for firing to remove residual wax and moisture, and to improve the strength and refractoriness of the mold shell. The firing process requires strict control of temperature and heating rate to prevent cracking or deformation of the mold shell.

The titanium alloy raw material is placed in a vacuum induction furnace for melting. During melting, the vacuum level and temperature inside the furnace must be strictly controlled to ensure the uniformity and purity of the titanium alloy composition. When the titanium alloy reaches the appropriate casting temperature, it is quickly poured into the preheated mold shell. The casting process must be carried out under a protective atmosphere to prevent the titanium alloy from reacting with oxygen, nitrogen, etc., in the air at high temperatures.

After casting, the casting is allowed to cool naturally in the mold shell. The cooling rate affects the microstructure and properties of the titanium alloy and needs to be controlled according to specific circumstances. After cooling, break the mold shell, remove the casting, and remove excess parts such as the sprue and riser. Then clean and polish the casting to achieve the designed surface finish.

A comprehensive quality inspection is performed on the cleaned oil separator casting. This includes dimensional accuracy inspection, using measuring tools (such as calipers, micrometers, etc.) to measure key dimensions such as the inner diameter, outer diameter, and length of the oil separator to ensure it meets the design drawings; non-destructive testing, such as using X-ray flaw detection and ultrasonic flaw detection to detect internal defects such as cracks and porosity; and performance testing, testing the corrosion resistance, strength, and other properties of the oil separator to ensure it meets the atomizer's usage requirements.

* Challenge: Titanium alloys have high chemical reactivity and easily react with oxygen and nitrogen in the air at high temperatures to form oxides and nitrides, thereby reducing the performance of the casting. Meanwhile, titanium alloys have high melting points, requiring significant energy consumption during melting and casting, and placing high demands on equipment.

* Solution: Employ a vacuum induction melting furnace, maintaining a high vacuum or inert gas protective atmosphere (such as argon) within the furnace during melting and casting to prevent contact between the titanium alloy and air. Simultaneously, select high-quality melting equipment, improving heating efficiency and temperature control accuracy to ensure the titanium alloy melts fully and reaches the appropriate casting temperature.

* Challenge: Titanium alloys can chemically react with the mold material at high temperatures, leading to defects such as sand adhesion and peeling on the mold surface, affecting the surface quality and dimensional accuracy of the casting.

* Solution: Select refractory materials with good compatibility with titanium alloys for the mold, such as yttrium oxide-based refractories. Simultaneously, apply a special insulating coating to the mold surface to reduce the chemical reaction between the titanium alloy and the mold. Furthermore, optimize the mold manufacturing process to increase its density and strength, reducing its reactivity with the titanium alloy.

* Challenge: During lost-wax casting, defects such as porosity, shrinkage cavities, and cracks are prone to occur inside the casting. These defects severely affect the performance and reliability of the oil separator.

* Solutions: Optimize the design of the gating system, rationally setting the position and size of the gating system and risers to ensure that the molten titanium alloy can smoothly and evenly fill the mold shell, reducing the generation of porosity and shrinkage cavities. During the smelting process, use refining processes to remove gases and impurities from the molten titanium alloy, improving its purity. Simultaneously, control the cooling rate of the casting to avoid cracks caused by uneven cooling. For defects already discovered, repair methods such as welding and grinding can be used.