What is the cleaning range and method of fine castings? The foundry says that cleaning is the process of removing the fine castings from the mold, removing excess parts outside the valve body, and polishing and trimming the inside and outside surfaces of the castings. Nodular cast iron

Core removal and surface cleaning:

Foundry said, divided into dry method and wet method two major categories. Dry cleaning is the use of mechanical equipment to clean castings. The equipment used is simple, the production efficiency is high, the adaptability of different types of castings is large, can effectively remove the core and clean the surface. The disadvantage is dust flying, noise, pollution of the environment. There is no dust in wet cleaning, but because water is the medium, the surface of the casting is easy to rust. A lot of sewage and cement sand are produced in the process of operation, which brings problems such as sand water regeneration and sludge treatment.

Common dry cleaning and wet cleaning in production are:

Roller cleaning. Castings and pig iron are placed in circular drums, the foundry said. When the drum rotates, the sand inside and outside the casting can be removed by the mutual impact and friction between the casting, pig iron and waste sand, polishing the surface of the casting, and also partial removal of flying burrs. This equipment is suitable for cleaning small and medium-sized castings with simple shape and large wall thickness.

Shot blasting cleaning. High-speed steel pellets, iron wan and abrasive flow are used to remove the sand core and sand the surface of the casting, the foundry said. In addition, the commonly used shot blasting cleaning equipment includes shot blasting cleaning table and shot blasting cleaning room. Shot blasting machine for continuous production includes chain type shot blasting drum, continuous shot blasting platform, continuous production hanging shot blasting room, etc. This equipment is expensive to operate and maintain.

Hydraulic sand cleaning. The foundry says high-pressure water is sprayed over the treated castings from the nozzle of a spray gun through a pipe, and relies on the kinetic energy and scouring of the water to clean up sand stuck to the cores and castings. Hydraulic sand cleaning is usually equipped with an open cleaning room consisting of section and steel plates with a turntable at the bottom. The gun is mounted on the side wall and can be moved up and down and rotated, allowing high-pressure water to be sprayed anywhere but the bottom of the casting. Sometimes, in order to improve the desanding efficiency of the surface of fine castings, abrasive materials such as quartz sand are introduced in the appropriate position of the spray gun to obtain high speed water sand flow. Generally this method is called water sand cleaning.

Water sandblasting. After casting, when the casting has cooled to the specified temperature, box it up and immediately dip it into the tank, the foundry says. Water penetrates into the casting through all the gaps, and contacts with high temperature metal to vaporize and explode rapidly. Shock wave can basically clean the sand attached inside and outside the casting. Water spraying sand clearing method has the advantages of short operation time and high efficiency, and it is widely used in cast steel workshop. It is generally used to deal with simple steel castings with carbon content below 0.35%.