The quality of alloy steel castings is effective in the mass operating and inherent quality, as well as appearance quality. In the cooling process of alloy steel castings should be effective scatter in a dry place, work piece should be promptly tempering after quenching, the time interval should not be commonly more than 4 h, work piece used carbon alloy steel castings (carbon mass fraction) is low, the shape is simple and should not be more than 16 h.
Alloy steel castings cooling to rear can wash, cryogenic treatment or tempering operation, welding assembly of alloy steel castings, the time interval between welding and subsequent heat treatment should not be more than 4 h products in cooling, we have to request according to the work piece and the surface condition using alkaline cleaning, water-soluble solvent cleaning agent, chlorine sandblasting, shot blast cleaning methods such as alloy steel castings, to ensure better cooling effect into full play.
Classification of alloy steel castings.
1. Low alloy cast steel castings, in China they are mainly apply with manganese series, manganese silicon and chromium series, such as ZG40Mn, ZG30MnSi1, ZG30Cr1MnSi1, etc.It is used to make parts such as gear, hydraulic machine working cylinder and turbine rotor, and ZG40Cr1 is commonly used to make high-strength gear and high-strength shaft, etc.
2. High alloy steel castings, wear-resisting, high temperature and corrosion resistance and other special performance, such as high manganese steel ZGMn13, is a kind of wear-resistant steel, mainly used in the manufacture of parts are used for dry friction conditions, such as the anterior wall of the excavator grab and grab bucket tooth, and tanks of crawler tractor, etc.;Chromium nickel stainless steel ZG1Cr18Ni9 and chromium stainless steel ZG1Cr13 and ZGCr28, etc., have high corrosion resistance to nitric acid, mainly used in manufacturing chemical, petroleum, chemical fiber and food equipment.
Heat treatment process of alloy steel castings.
Heat treatment methods include: annealing, normalizing, normalizing plus tempering.The mechanical properties of the three methods are different, which is not too complicated for the general shape.For casting steel nodes with complicated shape, easy to deform and crack, it is appropriate to use annealing.It is used for thick carbon steel castings and low alloy steel parts.The purpose of tempering is to eliminate the stress of cast steel joints both avoid deformation and cracking of steel joints.http://www.pump-casting.com/