Quality Nickel Alloy Casting & Cobalt Alloy Castings factory

Chinese Lost wax process originated from Burning Loss method which can be dated back to the middle and the late periods of Shang Dynasty. The Burning Loss method started dying off after the development of Lost wax process. Lost wax process is a precesion casting process used to cast ware which is made of brozen and other materials. The process is that engineers should make a mold which is made of beewax, then the lame core and outside parts will be made from other fire-proof materials. With the heating process,the whole wax pattern will be melted, running away. So the whole casting mold will be empty. The engineers will pour molten metal into mold, then get a casting.. The advantages of lost wax process: 1. The castings significant feature of high precision and high finishi. The dimensional precision can reach to 5% of nominal size. And the roughness level is Ra0.8-3.2μm， which can help us prove the efficiency of machining. 2. The mechanical properties of the castings produced by Lost wax process are superior, and the costs are lower. 3. Comprehensive material adaptability. 4. Good production flexibility. Lost wax process is suitable for mass production,small-lot production, even the unit production.

A non-ferrous alloy formed by adding other elements to molybdenum as a matrix. The main alloying elements are titanium, zirconium, hafnium, tungsten and rare earth elements. Titanium, zirconium, and molybdenum alloy hafnium elements not only play a solid solution strengthening effect on the molybdenum alloy, maintain the low-temperature plasticity of the alloy, but also form a stable and dispersed carbide phase to improve the strength and recrystallization temperature of the alloy. Molybdenum alloy has good thermal conductivity, electrical conductivity and low expansion coefficient. It has high strength at high temperature (1100~1650℃) and is easier to process than tungsten. It can be used as the grid and anode of the electron tube, the support material of the electric light source, and used to make die-casting and extrusion molds, and the parts of spacecraft. Because molybdenum alloy has low temperature brittleness and welding brittleness, and high temperature is easy to oxidize, its development is limited. Industrially produced molybdenum alloys include molybdenum-titanium-zirconium, molybdenum-tungsten, and molybdenum rare-earth alloys. The most widely used is the first type. The main strengthening methods of molybdenum alloys are solid solution strengthening, precipitation strengthening and work hardening. Through plastic processing, molybdenum alloy plates, strips, foils, pipes, bars, wires and profiles can be prepared, and its strength can be improved and low-temperature plasticity can be improved.

Stellite is a hard alloy that can withstand various types of wear, corrosion and high temperature oxidation. It is commonly referred to as cobalt-chromium-tungsten (molybdenum) alloy or cobalt-based alloy. Stellite alloy was invented in 1907 by American Elwood Hayness. Stellite alloy is a type of alloy with cobalt as the main component, containing a considerable amount of nickel, chromium, tungsten and a small amount of alloying elements such as molybdenum, niobium, tantalum, titanium, and lanthanum, and occasionally also containing iron. According to the different composition of the alloy, they can be made into welding wire, powder used for hard surface welding, thermal spraying, spray welding and other processes, and can also be made into castings and forgings and powder metallurgy parts.

1. Introduction Tungsten carbide valve ball or carbide ball valve is evolved from the traditional plug valve. Its opening and closing part is a sphere, and the purpose of opening and closing is realized by the sphere around the axis of the valve stem. High-precision tungsten-cobalt cemented carbide balls are widely used in oil drilling and deep sea drilling oil pump valve balls and ball seats, which are also one of the most critical components in oil well pumps. Due to the harsh working environment and conditions in the oil drilling industry, there are usually some highly corrosive substances such as water, various gases, wax, sand, etc. in sand-bearing wells, heavy oil wells, and high-pressure oil-repellent wells. To extract oil from hundreds or even thousands of meters of formation, it requires the valve ball and seat to have good sealing performance, wear resistance and corrosion resistance (after the valve ball and valve seat are matched, vacuumize to an absolute pressure of 0.36kgN /cm below, the absolute pressure value does not change within 10s). 2. Advantages The main advantages of carbide ball valves can be divided into the following aspects: 1. It has the lowest flow resistance in theory (flow resistance refers to the ratio of the pressure difference on both sides of the sound-absorbing material sample to the linear velocity of the air flow passing through the sample under a steady airflow state); 2. Excellent chemical stability and wear and corrosion resistance, can be in contact with most liquids and some corrosive media; 3. In the environment of high temperature and high pressure, it can still achieve complete sealing (nominal pressure from vacuum to 42MPa); 4. Since the tungsten carbide ball valve uses the ball as the opening and closing part, it is less affected by friction, and can realize rapid opening and closing (can be controlled within 0.05-0.1s), and the impact of the operation is small. In addition, the spherical closing The parts can withstand high pressure difference when closing, and can also realize automatic positioning; 5. It has two-way sealing, which makes the work more stable and reliable. 3. Application Applicable occasions for several common carbide ball valves: 1. It is suitable for pipeline systems with two-position adjustment, high requirements for sealing performance, rapid opening and closing (1/4 turn opening and closing), large pressure difference, small operating torque, small flow resistance, and cavitation or vaporization. Use carbide ball valve; 2. In pipelines with certain corrosive media; 3. In low-temperature cryogenic devices or high-temperature and high-pressure piping systems; 4. Full-bore welded carbide ball valves can be used in oil pipelines and gas pipelines that need to be buried underground; 5. The specially designed V-shaped opening structure carbide ball valve can also have a certain adjustment function. In addition, the application range of cemented carbide balls is very wide, such as: balls, navigation systems, stamping and stretching of precision parts, precision bearings, instruments, meters, pen making, spraying machines, water pumps, mechanical parts, sealing valves, brake pumps , punching, oil field, hydrochloric acid laboratory, hardness measuring instrument, high-quality fishing gear, counterweight, finishing and other industries!

Heat-resistant steel precision castings should be stacked reasonably according to the layout characteristics during heat treatment to prevent deformation as much as possible. When the segregation of the as-cast arrangement of the casting is serious, in order to eliminate the influence on the function of the end of the casting, a unified treatment method needs to be adopted. In the as-cast arrangement, there are often coarse dendrites and segregation. During heat treatment, the heating temperature should be slightly higher than that of forgings with the same composition, and the austenitizing holding time should be appropriately extended. For steel castings with messy shapes and large wall thicknesses, section effects and casting need to be considered during heat treatment. The main elements of high temperature oxidation and high temperature corrosion resistance in heat-resistant steel precision castings can improve the thermal strength of heat-resistant steel. The high temperature corrosion resistance of heat-resistant steel has a certain relationship with its chromium content. Therefore, the chromium content of commonly used heat-resistant steels should not be lower than nickel, which is one of the important alloying elements in heat-resistant steels. In order to obtain the pure austenite structure of the steel at normal temperature, the nickel content is not less than 25%. However, when the steel contains other alloying elements, in order to obtain a pure austenite structure, the nickel content can be appropriately reduced. How to clean heat-resistant steel precision castings Heat-resistant steel precision castings are one of the castings. The cleaning of heat-resistant steel precision castings is divided into general cleaning, ultrasonic cleaning, degreasing cleaning and vacuum cleaning. They have their own characteristics, and the formulations of the cleaning solutions used are different. Generally, there are solvent-based cleaning solutions and water-based cleaning solutions. In the actual cleaning process of heat-resistant steel precision castings, the most used ones are: 1. Metal cleaner It is mostly used for cleaning before heat treatment and chemical heat treatment of heat-resistant steel precision castings 2.3%-10% sodium carbonate or sodium hydride cleaning solution, the temperature is controlled at 80-100°C, it is mostly used for degreasing and salt slag finishing of heat-resistant steel precision castings after quenching.