What does sludge quenching and tempering mean, and what does quenching and tempering mean?

Sludge quenching and tempering: some sludge contains oil or other organic substances, which encapsulates the water, which is not conducive to dewatering, so it is necessary to add a conditioner, generally lime or polymer flocculant, to facilitate sludge dewatering.

Sludge is a product of sewage treatment and is an extremely complex heterogeneous body composed of organic residues, bacterial bacteria, inorganic particles, colloids, etc. The main characteristics of sludge are high moisture content (up to 99% or more), high organic matter content, easy to decay and smell, and fine particles, small specific gravity, and gelatinous liquid. It is a thick substance between liquid and solid and can be transported by pump, but it is difficult to separate solids from liquid by sedimentation.

Sludge conditioning calcium hydroxide (slaked lime) I. Basic overview 1Aliases: slaked lime, hydrated lime 1

Main components: Ca(OH)2, molecular weight 1Production Method:

The finished product is obtained by calcium oxide, i.e., quicklime digested with water, drying, sieve, and winnowing (or grading and crushing). 1.Physicochemical properties:

Fine white powder, strongly alkaline. It is placed in the air to gradually absorb carbon dioxide and turn it into calcium carbonate. Slightly soluble in water, soluble in acid.

density, its clear aqueous solution is a colorless and odorless alkaline transparent liquid with a pH value. 1.The product refers to the implementation of Q 320586EAE04-1998 and GB T6852-86PH benchmark reagent calcium hydroxide, JC T481-92 and other standards.

Main Markets Environmental Protection Sewage (Wastewater) Treatment, Sludge Conditioning, Flue Gas Desulfurization, Tannery Impregnation Lime, Building Materials Raw Materials, Lacquermaking, Non-ferrous Metal Smelting, Stone Sand-sawing Chips, Soil Stabilization, Feed Additives, Building Adhesive Ingredients, etc.

Most of the quenched and tempered parts work under a relatively large dynamic load, they bear the action of tension, compression, bending, torsion or shearing, and some surfaces also have friction, requiring a certain degree of wear resistance and so on.

In short, the parts work under various compound stresses. This type of parts is mainly the structural parts of various machines and mechanisms, such as shafts, connecting rods, studs, gears, etc., which are commonly used in manufacturing industries such as machine tools, automobiles and tractors. Especially for large components in heavy machine building, quenching and tempering treatment is used more Therefore, quenching and tempering treatment occupies an important position in heat treatment.

The quenched and tempered parts in mechanical products, due to their different stress conditions, the required performance is not exactly the same. Generally speaking, all kinds of quenched and tempered parts should have excellent comprehensive mechanical properties, that is, the appropriate combination of high strength and high toughness to ensure the long-term smooth work of the parts.

Quenching and tempering usually refers to the heat treatment process of quenching + high temperature tempering to obtain tempered sostene. The method is to quench first, and the quenching temperature: AC3+30 50 for sub-eutectic steel; Ac1+30 50 for eutectic steel; Alloy steel can be slightly higher than carbon steel.

After quenching, tempering at 500 650 can be done. The main purpose of quenching and tempering is to obtain comprehensive mechanical properties with good strength and plasticity.

If it refers to quenching and tempering heat treatment, it is.

A heat treatment process for high-temperature tempering after quenching. It is suitable for medium carbon steel, with good comprehensive performance after quenching and tempering, and the hardness is 35-45HRC

Quenching and tempering refers to the heat treatment process through quenching and high-temperature tempering to obtain tempered soptenite. Quenching and tempering is a commonly used process. This treatment not only improves the strength, but also maintains the toughness of the material, and also improves the machinability of the material.

The heat treatment process of steel includes methods such as annealing, normalizing, quenching, tempering, and surface heat treatment. Among them, tempering also includes quenching and tempering treatment and aging treatment. Tempering of steel:

The quenched steel is reheated to a temperature of (350 650) according to the desired mechanical properties, and the carbon is precipitated in the form of a finely evenly distributed cementite. As the tempering temperature increases, the carbide particles increase, the yield point and tensile strength decrease, the hardness and brittleness decrease, and the elongation and shrinkage increase. The aim is to eliminate the internal stresses caused by quenching in order to achieve the desired mechanical properties.

Tempering is divided into three categories: high-temperature tempering, medium-temperature tempering and low-temperature tempering.

High temperature tempering: 500 650

Medium tempering: 300 450

Low temperature tempering: 150 250

Quenching and tempering treatment: The heat treatment method of high-temperature tempering after quenching is called quenching and tempering treatment. High temperature tempering refers to tempering between 500-650.

Quenching and tempering can make the performance and material of steel be adjusted to a great extent, and its strength, plasticity and toughness are good, and it has good comprehensive mechanical properties. After quenching and tempering, tempered sostenite is obtained. Tempered sorbite is formed by martensite during tempering, which can only be distinguished by magnification of more than 500 600 times under an optical mirror microscope, and is a composite structure of carbide (including cementite) chondrites distributed in a ferrite matrix.

It is also a tempered structure of martensite, which is a mixture of ferrite and granular carbide. At this time, the ferrite is basically free of carbon supersaturation, and the carbide is also a stable carbide. It is a balanced tissue at room temperature.

Quenching + high temperature tempering = quenching and tempering, quenching and tempering is the dual heat treatment of quenching and high temperature tempering, the purpose of which is to make the workpiece have good comprehensive mechanical properties.

The comprehensive treatment process of steel quenching and then high-temperature tempering is called quenching and tempering treatment.

That is: quenching and tempering treatment = quenching + high temperature tempering.

In engineering, the heat treatment combination of quenching + high temperature tempering is usually called quenching and tempering treatment, and the strength, hardness, plasticity and toughness obtained by the main purpose are matched with good comprehensive mechanical properties, which can be used as final heat treatment or as pre-heat treatment. The structure of the steel after quenching and tempering is: tempered sostenite structure.

The hardness value required after quenching and tempering is measured in Rockwell hardness value.

Quenching and tempering is a comprehensive heat treatment method of quenching + high temperature tempering, which is mainly used to improve the comprehensive mechanical properties of materials;

Hardness is an indicator of the hardness and softness of a metal material. HRC is a scale of Rockwell hardness, and when the hardness of the material is greater than HB (Brinell hardness) 450, it needs to be measured by a Rockwell hardness tester; Different scales can be measured according to different loading forces and indenters: HRA, HRB, HRC; HRC is the hardness obtained using a load of 150 kg and a diamond cone press.

The two together mean that the heat treatment method for the material is quenched and tempered, and the hardness of the quenched and tempered material should meet the requirements of HRC**.

HRC is the Rockwell hardness.

Quenched and tempered HRC means quenched and tempered hardness.

HRC and HB are two different hardness testing methods. Compared to HB, HRC is more suitable for materials with higher hardness after quenching, while HB is more suitable for annealed and unheated materials. The HRC hardness suitable for testing is HRC 20-67, which is equivalent to HB225-650, which cannot be measured or is inaccurate.

In this case, it is more accurate to use HB for measurements.

HRC is used when quenching is known, and the material obtained after quenching and tempering (after quenching + high temperature tempering) is labeled as HB, which can then be converted to HRC to compare with the hardness of the material after quenching.

HRC and HB are two different hardness test methods, HRC is more suitable for the hardness of materials with higher hardness after quenching, while HB is more suitable for annealed and unheat-treated materials. HRC 20 67, which is equivalent to HB225 650, is low, unmeasurable, or inaccurate, and it is more accurate to measure HB at this time.

Think of you in this situation:

HRC is used in quenching, and the material obtained after quenching and tempering (quenching + high temperature tempering) is marked as HB, then HB can be converted into HRC to compare with the hardness of the material after quenching, (because the hardness of the quenching and tempering material is generally not very low, in this case, it is better to use HRC for comparison, and HRC is used as a reference when formulating the corresponding heat treatment process) and then formulate the relevant heat treatment process. The specific comparison can be done with reference to the hardness comparison table of 1L.

HB is the meaning of hardness, which means that the hardness of the modulation process should reach 225---250, and HRC is the meaning of Rockwell hardness.

Both are used to indicate the hardness of a part, with the former generally used for large blanks and the latter generally used for machined parts.

The so-called quenched and tempered steel, is the product of quenching and tempering at high temperature, after quenching and tempering steel, its strength, toughness, stiffness, corrosion resistance, high temperature resistance, wear resistance and other properties will be significantly increased, mainly used for connecting rods, etc., in addition to bearings, tool steel should be used.

Attention: 1469 low-carbon low-alloy quenched and tempered steel generally has high yield strength (450-980MPa), good plasticity, toughness, and wear resistance and corrosion resistance. According to different uses, different alloy compositions and different heat treatment systems can be used to obtain low-carbon low-alloy quenched and tempered steel with different comprehensive properties.

1) Steel is mainly used in engineering mining machinery.

Structural steel products used in large quantities are usually quenched and heat-treated, which not only consumes energy but also brings disadvantages to heat-treated parts, such as deformation and quenching. Non-quenched and tempered steel is to add trace elements V, Ti, etc. to the steel, through the controlled forging (rolling) process, so that the alloying elements are dispersed and precipitated by C and N compounds, so that the steel reaches the level of quenched and tempered strength, thereby eliminating the quenching and tempering treatment, simplifying the production process, saving energy, and has certain economic benefits. Non-quenched and tempered steel is mainly used in automobile engines, tractor engines, connecting rods of air compressors, machine tool parts, shaft parts, etc.