Floor molding is a traditional sand molding process. Floor molding means we make the sand castings on floor or ground by sand boxes.
The deference from other casting method is we use green sand or resin sand, and mold by manual, not by molding machines. It is a kind of old and traditional molding method, but is still widely used in China and worldwide.
As we know, floor molding uses sand as the molding material, which has low cost, easy mold manufacturing, suitable for small production volume and mass production. So, floor molding has been the basic technology of casting production.
Floor molding has existed for many years, and usually uses green sand and resin sand as the molding materials.
The most commonly used casting sand is silica sand. Silica sand can not meet the basic requirements of temperature. Chromites sand and other special corundum sand will be used for special temperature requirements. In order to make the sand mold and core with a certain intensity, casting foundries usually add sand binder, in this way, loose sand will bond together to form the molding sand. Sand binder most widely used is clay, may also have a variety of drying oil or semi-dry oil, water-soluble silicates or phosphates, and various synthetic resin for molding sand binder. According to the difference of sand binders, molding sand can be classified into the wet clay sand, or called green sand, dry clay sand and chemical hardening sand.
Although the foundries use different sands, the molding is still called floor molding. In China, we usually call it as wet sand molding, or green sand molding, but in western countries, it is still called floor molding, or floor moulding.
This article was from Dandong Foundry Blog .
This standard is for gray iron castings used for general engineering use where tensile strength is a major consideration. Casting degrees are classified on the basis of the tensile strength of the cast test bars. This standard also provides the chemical composition and physical properties for motor vehicles.
According the minimum tensile strength obtained by test bars, designers could choose the suitable gray iron degrees. The following information is from ASTM.
This article was from Dandong Foundry Blog.
For the whole article, please check Dandong Foundry Blog.