Heat treatment method capable of improving elongation rate of PCrNi3MoVA material forge piece

A heat treatment method and elongation technology, which are applied in the production field of large-section ultra-high pressure vessel forgings for medium alloy structural steel, can solve the problem of difficult to meet elongation requirements, improve elongation and impact toughness, improve original structure, operation strong effect

Active Publication Date: 2018-11-30
武汉重工铸锻有限责任公司
View PDF7 Cites 4 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] Due to the high strength and high impact toughness of this material, it has been widely used in ultra-high pressure vessel forgings. As the pressure vessel equipment is used in more and more fields, the pressure and cross section of the pressure vessel equipment are also increasing. Therefore, The elongation required by this material is in large cross-section forgings. It is difficult to meet the elongation requirements by using conventional quenching and tempering heat treatment methods. The performance meets the technical requirements

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0024] Heat treatment The effective cross-section of PCrNi3MoVA material forging heat treatment is φ120mm, and its chemical composition (%, wt, melting analysis) is as follows: C: 0.32%, Si: 0.26%, Mn: 0.66%, P: 0.008%, S: 0.005%, Cr: 1.50%, Ni: 3.45%, Mo: 0.35%, V: 0.20%, Cu: 0.10%, and other elements meet the requirements.

[0025] The specific steps of heat treatment are as follows:

[0026] 1) First heat the PCrNi3MoVA material forging to 610°C and keep it warm for 2 hours, then raise the temperature to 890°C and keep it warm.

[0027] 2) Heat the PCrNi3MoVA material forging that has been cooled to room temperature in step 1) to 610°C and keep it warm for 2 hours, then raise the temperature to 870°C and then keep it warm. The holding time is calculated as 1h according to 0.8h / 100mm; To 780°C, keep warm for 1 hour, then take out the furnace and quench;

[0028] The quenching method is water cooling, air cooling, secondary water cooling, and then oil cooling; the water coo...

Embodiment 2

[0032] Heat treatment The effective cross-section of PCrNi3MoVA material forging heat treatment is φ150mm, and its chemical composition (%, wt, melting analysis) is as follows: C: 0.34%, Si: 0.25%, Mn: 0.6%, P: 0.006%, S: 0.005%, Cr: 1.40%, Ni: 3.4%, Mo: 0.35%, V: 0.18%, Cu: 0.15%.

[0033] The specific steps of heat treatment are as follows:

[0034] 1) First heat the PCrNi3MoVA material forging to 630°C and keep it warm for 2 hours, then raise the temperature to 880°C and keep it warm.

[0035] 2) Heat the PCrNi3MoVA material forging that has been cooled to room temperature in step 1) to 630°C and keep it warm for 2 hours, then raise the temperature to 860°C and keep it warm. The holding time is calculated as 1.2h according to 0.8h / 100mm; Lower it to 780°C, keep it warm for 1 hour, then take it out of the furnace and quench it;

[0036] The quenching method is water cooling, air cooling, secondary water cooling, and then oil cooling; calculated: the water cooling time is c...

Embodiment 3

[0040] Heat treatment PCrNi3MoVA material forging heat treatment effective section is φ200mm, its chemical composition (%, wt, melting analysis) is as follows: C: 0.35%, Si: 0.30%, Mn: 0.7%, P: 0.007%, S: 0.005%, Cr: 1.50%, Ni: 3.5%, Mo: 0.40%, V: 0.20%, Cu: 0.11%.

[0041] The specific steps of heat treatment are as follows:

[0042] 1) First heat the PCrNi3MoVA material forging to 620°C and keep it warm for 2 hours, then raise the temperature to 900°C and keep it warm.

[0043] 2) Heat the PCrNi3MoVA material forging that has been cooled to room temperature in step 1) to 620°C and keep it warm for 2 hours, then raise the temperature to 880°C and keep it warm. The holding time is calculated as 1.6h according to 0.8h / 100mm; Lower to 790°C, keep warm for 2 hours, then take out the furnace and quench;

[0044] The quenching method is water cooling, air cooling, secondary water cooling, and then oil cooling; it is calculated that the water cooling time is 5 minutes according to...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
elongationaaaaaaaaaa
elongationaaaaaaaaaa
Login to view more

Abstract

The invention relates to a heat treatment method capable of improving an elongation rate of a PCRni3MOVA material forge piece. The method comprises the following steps that normalizing is conducted toheat to 610-650 DEG C firstly, then heating up to 880-900 DEG C is conducted, then heat preservation is conducted, and cooling to a room temperature is conducted; quenching is conducted to heat to 610-650 DEG C firstly, then heating up to 860-880 DEG C is conducted, the heat preservation is conducted, cooling and quenching are conducted, taking out of a furnace is conducted, and water cooling, air cooling, secondary water cooling and oil cooling are conducted for cooling and quenching; tempering at a high temperature is conducted to heat to 320-350 DEG C firstly, then preserving heat is conducted, and then heating up to 580-610 DEG C is conducted; after the furnace cooling to 400 DEG C is conducted, and taking out of the furnace is conducted for the air cooling. According to the method, the heat treatment mode of normalizing, cooling and quenching and high-temperature tempering is adopted, the material forge piece with a effective section phi 101 mm to phi 250 mm can be subjected to heat treatment, the elongation rate of the material forge piece subjected to the heat treatment can reach 16%-19%, technical requirements of an ultra-high pressure container forge piece can be met, andthe production process is high in operability.

Description

technical field [0001] The invention relates to the technical field of production of large cross-section ultra-high pressure container forgings for medium alloy structural steel, and mainly relates to a heat treatment method capable of improving the elongation rate of PCrNi3MoVA material forgings. Background technique [0002] General PCrNi3MoVA heat-treated forgings are small forgings with an effective cross-section ≤ 100mm. Its chemical composition (%, wt, smelting analysis) is as follows: C: 0.32% ~ 0.42%, Si: 0.17% ~ 0.37%, Mn: 0.20% ~ 0.80%, P≤0.012%, S≤0.008%, Cr: 1.20 %~1.50%, Ni: 3.00%~3.50%, Mo: 0.35%~0.45%, V: 0.10%~0.25%, Cu≤0.20. The heat treatment method is: heating to 860 ~ 880 ℃ for quenching, and the holding time is calculated as 2h / 100mm. Tempering: Heating to 550-620°C and then holding the heat. The holding time is calculated as 2.0h / 100mm, and the trolley is taken out of the oven and air-cooled. The sampling position for the performance test of small fo...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): C22C38/02C22C38/04C22C38/44C22C38/46C22C38/42C21D1/18
Inventor 汤晶晶张承峰熊武刘国平周预平邹泉马晓兵潘小飞罗波
Owner 武汉重工铸锻有限责任公司
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap