Torque Normalizing Of Heat Treatment Of Machinery Casting Part

Torque normalizing of heat treatment of Machinery Casting Part
The precision foundry will have a heat treatment process in the production of the Machinery Casting Part. The reason is mentioned in the previous article. The following is a major part of the process that the Machinery Casting Part has an indispensable process in the heat treatment process. Normalizing.
Tempering
Machinery Casting Part The purpose of product tempering is as follows:
1, reduce the brittleness, eliminate or reduce the internal stress, Machinery Casting Part after quenching there is a lot of internal stress and brittleness, if not timely tempering will often make the Mechanical Casting Part deformation or even cracking.
2, to obtain the required mechanical properties of the workpiece, the workpiece after quenching high hardness and brittle, in order to meet the different requirements of various workpiece requirements, with the appropriate tempering to adjust the hardness, reduce the brittle, get the required Toughness, plasticity.
3, stable workpiece size
4, for the annealing is difficult to soften some of the alloy steel, quenching (or normalizing) after the use of high temperature tempering, so that the proper accumulation of carbide in the steel, the hardness reduced to facilitate the cutting process.
Normalizing
The production of Machinery Casting Part also requires normal fire
Normalizing is the heat treatment process that heats the Machinery Casting Part to above the critical temperature of 30-50 ° C and is cooled in the still air after proper temperature for holding it. The main purpose of normalizing is to refine the organization, improve the performance of steel, get close to the balance of the organization.
Normalizing and annealing process compared to the main difference is the normalizing of the cooling rate is slightly faster, so the normalizing heat treatment of the production cycle is short. So the same annealing and normalizing parts to meet the performance requirements, as far as possible the use of normalizing. Most of the low carbon steel blanks are generally used in normalizing heat treatment. General alloy steel billet often used annealing, if the normalizing, due to the cooling faster, so that the normalized high hardness, is not conducive to cutting.
Each qualified Machinery Casting Part product, must be strictly through the various links, each link of the small differences, and ultimately affect the quality of the product.
Different Machinery Casting Part structure of the subsequent processing content and the difficulty is also different, the general Machinery Casting Part cast after crushing, cutting, grinding, shot blasting and other processes can be, and some Machinery Casting Part need to increase the process. Factors that determine the difference in post-processing costs: Clean sand, corrective deformation and refurbishment, the cost of which depends on the structure and technical requirements of the Machinery Casting Part, and the cost difference should be taken into account when approving the price.
1, sand: some with a long slot or slender hole of the Machinery Casting Part sand more difficult, need to drill sand, biting acid, sandblasting or alkali explosion to clean up. Such a Machinery Casting Part requires a separate estimate of sand removal costs.
2, plastic: easy to deformation of the Machinery Casting Part need to correct its deformation, the difficulty of shaping depends on the Machinery Casting Part structure, deformation and customer size and shape and position tolerance requirements. Plastic costs should be accounted for separately.
3, renovation: casting process is a special process, the impact of Machinery Casting Part quality factors are more. Objectively speaking, the mechanical imperfections of the Machinery Casting Part are difficult to avoid. Different requirements for surface quality are different for different customer or different uses. The supply and demand sides prior to the order are determined by a reasonable quality based on the characteristics of the Machinery Casting Part and possible surface defects Acceptance criteria are very important. If the customer's surface quality requirements are relatively high, the cost of renovation is relatively high. Refurbishment costs are mainly affected by the quality requirements of the Machinery Casting Part and the rate of passability of the Machinery Casting Part, which requires consideration in pricing and the latter depending on the internal quality control. Refurbishment costs can be adjusted on the basis of the average cost of the post-processing multiplied by the appropriate quality rating factor.