32results about How to "Reduces shrinkage tendency" patented technology

The invention relates to a furan resin sand mold for producing heavy castings and a sand core bumping method. According to the technical scheme of the invention, the bumping method comprises the following steps of: a, correcting a table-surface level of a bumper first when the bumper is arranged and then checking up accelerations at four corners of the table-surface by using a seismometer and keeping the numerical values of the accelerations of the four angles to between 20 and 30 m / s<2>; b, adding a furan resin and a furan self-hardening sulfuric curing agent into molding sand and stirring the mixture to obtain sand mud for making mold and core sands, wherein the added weight of the furan resin is 0.95 to 1.15 percent based on the added weight of the molding sand and the added weight of the furan self-hardening sulfuric curing agent is 35 to 45 percent based on the added weight of the furan resin and the sulfuric acid in the furan self-hardening sulfuric curing agent is 9 to 35 percent by weight; and c, pouring the sand mud into a box till the level of the sand mud is 100 to 150 millimeters higher than the box surface and then starting the bumper to perform bumping for 10 to 50 seconds. The method has the advantages of greatly improving the percent of pass, greatly improving the loosening conditions of the casting and greatly reducing the rejection rate.

The invention relates to a single cylinder diesel engine body and particularly relates to a vermicular graphite cast iron single cylinder diesel engine body with high vermicular graphite rate. The single cylinder diesel engine body comprises the following chemical components in percentage by mass: 3.5-3.8% of C, 2.1-2.6% of Si, 0.5-0.8% of Mn, less than 0.08% of P, less than 0.03% of S and the balance of iron and inevitable impurities. The single cylinder diesel engine body provided by the invention has the characteristics of less inclination of shrinkage cavity and shrinkage porosity and long service life. The invention further provides a preparation method of the single cylinder diesel engine body, which is reasonable in process.

The invention discloses a large cylindrical shell aluminum alloy casting low-pressure casting and shrinking control device. The large cylindrical shell aluminum alloy casting low-pressure casting and shrinking control device comprises a sand box, a casting, a pouring system, vibrators and vibration guide rods. The vibration guide rods are connected between a vertical cylinder pouring channel of the pouring system and the sand box. The vibrators are arranged on the outer surface of the sand box. The vibration direction of the vibrators is in line with the direction of the guide rods and tightly connected with the guide rods. The vibrators are adopted for providing a vibration source, the vibration guide rods are used for vibrating and guiding the casting and vibration is generated in the casting. Vibration transmitted by the guide rods is used for eliminating shrinking formed in the casting in the solidifying process. The vibrators vibrate in the normal direction of the outer surface of the cylindrical sand box and the guide rods are arranged in the normal direction of the outer surface of the sand box and coincide with the vibration direction of the vibrators. Meanwhile, the direction of the guide rods is parallel to the normal direction of the outer surface of the casting. According to the large cylindrical shell aluminum alloy casting low-pressure and shrinking control device, the density of the casting is reduced, the tendency to shrinking of the casting is relieved and the qualification rate of the casting is greatly improved.

The invention discloses high-wear-resistance long-life ductile iron, comprising, by weight, 3.80-3.88% of C, 2.20-2.30% of Si, 0.55-0.65% of Mn, < / =0.020% of P, < / =0.010% of S, 0.45-0.55% of Cu, 0.30-0.40% of Mo, 0.0040-0.0060% of La, 0.035-0.045% of Mg, and the balance of iron and unavoidable impurity. The invention is intended to provide the high-wear-resistance long-life ductile iron that has high rigidity and fatigue strength and has improved tensile strength and plasticity, and a method of producing a lower cylinder with the ductile iron.

The invention discloses a sampling device for accurate quantification of carbon content in spheroidal graphite cast iron and additionally discloses a sampling method using the sampling device for the accurate quantification of the carbon content in the spheroidal graphite cast iron. According to the technical scheme of the invention, the sampling device for the accurate quantification of the carbon content in the spheroidal graphite cast iron comprises a sampling base and a sampling handle. A sampling cavity is arranged on the sampling base. The wall surface of the sampling cavity is a spherical crown surface. The sampling handle comprises an operating handle and a sampling ball. The sampling ball is connected with the bottom end part of the operating handle. The diameter of the sampling ball is the same as the diameter of the sampling cavity. By using the device, the precision of carbon content detection is improved, the operation is convenient and the shrinkage trend of castings is reduced.

The invention relates to vermicular graphite cast iron with a high rate of vermiculation of a combustion motor cylinder body and a cylinder cover and a preparation method, and belongs to the field of casting method. The vermicular graphite cast iron with the high rate of the vermiculation of the combustion motor cylinder body and the cylinder cover and the preparation method are characterized in that the vermicular graphite cast iron with the high rate of the vermiculation comprises the following chemical components: 3.4%-3.7% of carbon, 2.0%-2.5% of silicon, 0.5%-0.8% of manganese, 0%-0.08% of phosphorus and 0%-0.04% of sulphur, with the balance being iron. In a microscopic structure, a pearlite area accounts for 50%-70%, a ferrite area accounts for 30%-50%. The mechanical properties are as follows: strength of extension sigma b is more than or equal to 320 MPa to 400 MPa, ductility delta is 1%-4%, and hardness HB is 160-230. Due to the fact that molten iron component is near an eutectic point, scope of crystallization is narrow, liquidity is good, casting performance is good, the tendency of a casting shrinkage cavity and shrinkage porosity is little, a wholesome cylinder cover cast and wholesome cylinder body cast are easy to obtain, the service lives of the cylinder cover and the cylinder body are prolonged, certainly, the vermicular graphite cast iron with the high rate of the vermiculation of the combustion motor cylinder body and the cylinder cover and the preparation method play a pivotal role of the performance of improving the combustion motor and prolonging the service life of the combustion motor.