Valve retainer

Abstract

The invention discloses a valve retainer, which is made of a powdered metal material that comprises the following components in percentage by weight: 0.8 to 1.3 percent of C, 2.0 to 4.0 percent of Cr, 1.0 to 3.0 percent of Mo, 3.0 to 6.5 percent of Co, 0.5 to 2.0 percent of Ni, 0.8 to 1.5 percent of Mns, 0.05 to 0.1 percent of P, 0.2 to 0.5 percent of V, less than or equal to 3 percent of other elements and the balance of Fe. A prevention segregation agent is added into the powdered metal material which can make valve retainer. The valve retainer disclosed by the invention can resist high temperature and wear, and resist the high temperature of over 800 DEG C. In a bench test of more than 300 hours, the valve retainer does not generate segregation, which is favorable for cutting and ensuring the size precision and surface roughness of a cut face.

Description

technical field [0001] The invention belongs to a valve seat ring, in particular to a valve seat ring made of powder metal material. Background technique [0002] The traditional valve seat in our country is made by melting and casting various alloy elements, which has a low level of technology, backward technology and poor product consistency. Because the casting is melted at high temperature, when it is cooled to room temperature, the structure at room temperature must be different due to the different cooling rates of the core and the edge. The stress is large, and it is easy to produce processing and use deformation. [0003] Because there are metals with different densities in the formula, it is impossible to completely uniformly combine and dissolve during the melting process. Some of them are insoluble metals, such as molybdenum and other high-density metals, which must sink into the lower layer, and metal compounds with low density must float on the upper layer. Th...

AI Technical Summary

Problems solved by technology

[0002] The traditional valve seat ring in our country is made by melting and casting various alloy elements, which has a low level of technology, backward technology and poor product consistency.

Because the casting is melted at high temperature, when it is cooled to room temperature, the structure at room temperature must be different due to the different cooling rates of the core and the edge. Large stress, easy to produce processing and use deformation

[0003] Because there are metals with different densities in the formula, it is impossible to completely uniformly combine and dissolve during the melting process. Some of them are insoluble metals, such as molybdenum and other high-density metals, which must sink into the lower layer, and metal compounds with low density must float on the upper layer. This will cause segregation of components, uneven structure, uneven hardness and softness, resulting in uneven wear, resulting in air leakage on the sealing surface, reducing power, increasing energy consumption and exhaust emissions

[0004] It is very likely that some inclusions and air bubbles are not discharged in the casting, which will cause pores inside the product, resulting in a decrease in mechanical strength, air leakage on the sealing surface, and serious fracture

Since the castings are produced in a molten state, the energy consumption is high and the efficiency is low, and some alloy elements that are resistant to high temperature and wear cannot be added