CN101962735B

CN101962735B - Super-strength sucker rod steel

Info

Publication number: CN101962735B
Application number: CN2010102795715A
Authority: CN
Inventors: 王峰; 李子俊; 智建国; 井益农; 贺培基
Original assignee: BAOTOU FOUND PETROLEUM MACHINERY Co Ltd
Current assignee: FENGDA PETROLEUM EQUIPMENT CO., LTD.
Priority date: 2010-09-01
Filing date: 2010-09-01
Publication date: 2011-12-21
Anticipated expiration: 2030-09-01
Also published as: CN101962735A

Abstract

The invention relates to super-strength sucker rod steel which is characterized by comprising the following chemical components in percentage by weight: 0.23-0.46 percent of carbon (C), 0.1-0.3 percent of silicon (Si), 1.25-1.55 percent of manganese (Mn), less than 0.02 percent of phosphorus (P), less than 0.015 percent of sulphur (S), 0.05-0.15 percent of vanadium (V), 0.025-0.032 percent of chromium (Cr), 0.05-0.13 percent of rare earth (Re) and the balance of iron (Fe), wherein the rare earth is a mixture of lanthanum (La) and cerium (Ce). The invention has the advantages of high comprehensive mechanical property, overall consistent corrosion resistance, super strength and anti-corrosion, breaks the limits of technical means of shot blasting strengthening or electroplating chemical treatment, and the like to the strengthening or the anti-corrosion of the sucker rod and is a brand-new low-cost sucker rod material.

Description

The super-strength sucker rod steel

Technical field

The present invention relates to a kind of super-strength sucker rod steel, belong to the alloy steel material field.

Background technology

According to SY/T5029 " sucker rod " standard, conventional sucker rod is divided into by its mechanical property: K, C, D Three Estate, supporting capacity exceeds the D level, be that minimum stress is at 0-102Mpa, the sucker rod that the permissible stress value exceeds D level 35% mechanical property is the sucker rod of superstrength, and super-strength sucker rod is divided into again: material-type (code name HL) and two types of sucker rods of craft type (code name HY).Its regular size, promptly body of rod diameter is: four kinds of 5/8in (Φ 15.9), 3/4in (Φ 19.1), 7/8in (Φ 22.2) and 1in (Φ 25.4).

HY type sucker rod is selected to meet the YB/T054 standard except starting material, also must carry out surface strengthening and coating and handle, and be prone to surface imperfection, belongs to the craft type super-strength sucker rod.

HL type sucker rod is brought up to the superstrength grade by selecting suitable material (meeting the YB/T054 standard) for use with mechanical property, as material: 30CrMoA, belong to typical case's representative of material-type (HL type) super-strength sucker rod type, though its mechanical property conformance with standard requirement.But alloying element prices such as Mo wherein, W, Cr are all higher, cause the product prices of raw and semifnished materials more expensive.

But two kinds of superstrength HY types and HL type sucker rod are rich in H running into oil well well liquid ₂During corrosive mediums such as S, being easy to generate fatigue corrosion fracture lost efficacy, moreover each oil field oil recovery operating mode difference is bigger, be rich in various different corrosive mediums in the well liquid, make the sucker rod extent of corrosion that very big difference be arranged again, as: the well liquid in oil fields such as triumph, Central Plains, Xinjiang all contains a large amount of corrosive mediums, cause sucker rod shortening working life, and the oil well that deep-well, ultra deep well and big pump are adopted by force increases gradually, and the oil field presses for superstrength and corrosion resistance nature sucker rod stronger, that dual performance has both occurs.

HL type super-strength sucker rod relies on material itself to reach mechanical property requirements, but anticorrosion cracking performance is not good enough.HY type super-strength sucker rod reaches mechanical property requirements by means of surface strengthening or thermal treatment means, but after the surperficial coated layer generation spot corrosion, corrosion phenomenon increases the weight of rapidly, and corrosion resistance nature is also imperfect.

Summary of the invention

The purpose of this invention is to provide a kind of comprehensive mechanical performance height, the whole unanimity of corrosion resistance nature, and the stronger super-strength sucker rod steel of corrosion resistance.

In order to realize purpose of the present invention, the technical measures that adopt are: with D level pole stock matter is that the material of 25MnV is a parent chemical ingredients prescription, add suitable rare earth, chamber prescription and mechanical property and antiseptic property experimental result by experiment, adjust the dispensing ratio of each element of material, finally develop a kind of not only superstrength but also the novel material of sucker rod of acid-and base-resisting corrosive.

The chemical ingredients of super-strength sucker rod steel of the present invention is by weight percentage: carbon (C): 0.23-0.46%, silicon (Si): 0.1-0.3%, manganese (Mn): 1.25-1.55%, phosphorus (P): sulphur (S)＜0.02%:＜0.015%, vanadium (V): 0.05-0.15%, chromium (Cr): 0.025-0.032%, rare earth (RE): 0.05-0.13%, surplus is an iron, and wherein: rare earth is the mixture of element lanthanum (La) and cerium (Ce).

Advantage of the present invention is: comprehensive mechanical performance height, the whole unanimity of corrosion resistance nature, superstrength and anticorrosion having concurrently; Having broken through sucker rod is strengthened or the restriction of technique means such as anticorrosion employing shot peening strengthening or electroplating chemical processing, is a kind of completely newly material of sucker rod cheaply.

Embodiment

Embodiment: with D level pole stock matter is that the material of 25MnV is a parent chemical ingredients prescription, adds suitable rare earth.

(1) production technique:

Feed Si-Ca line-continuous small-billet casting-steel billet heating-bar continuous rolling-scale-inspection-packing warehouse-in after hot metal pretreatment-converter smelting-aluminium manganese silicon deoxidation-LF refining feeding rare-earth wires-refining in early stage.

(2) production smelting operation:

In the converter tapping process, adopt the Cr iron alloyization; The deoxidation of aluminium manganese silicon, LF refining feeding rare-earth wires in early stage is fed the Si-Ca line after the refining, and refining finishes to keep the soft blow of certain hour; Ladle direct casting platform is cast, specification 150mm * 150mm.

Because steel of the present invention are to be that the material of 25MnV is a parent chemical ingredients prescription with D level pole stock matter, add suitable rare earth and make, so called after: 25MnVRE.

The production testing data of 25MnVRE steel are as follows:

Round steel finished product chemical ingredients (weight %)

Round steel rolls the state property energy

Heat (batch) number	Specification (mm)	Rel(MPa)	Rm(MPa)	A(％)	Z(％)
						09102161	22	520、545	695、705	23、23	43.5、51.0
09102162	22	530、540	690、705	24.5、26	47.5、56.0
						09202208	22	525、555	685、720	23、23.5	44、46.0
09402010	19	600、615	770、785	22、23.5	42.5、44.5
						09501791	19	600、600	760、775	19.5、22.0	44、45
09202206	19	585、610	750、780	21.5、23.5	45、45.5
						09302015	19	590、605	750、770	23.0、24.0	50、54

Heat treatment performance

(heat treatment quenching and tempering back tension sample is processed into Φ 10mm for 880 ℃ of quenchings of sample (insulation 90min), 500 ℃ of tempering (insulation 60min), and impact specimen is processed into 10 * 10 * 55mm, tests then)

Heat (batch) number

Specification (mm)

Rel(MPa)

Rm(MPa)

A(％)

Z(％)

AKU(J)

09102161

22

910、950

1020、1070

14、16

58、58.5

102、112、116

09102162

22

910、980

1000、1070

16、17

60、60.5

144、151、158

09202208

22

995、1100

1090、1210

14.5、16

55.5、58.5

121、124、130

09402010

19

990、1120

1080、1220

14.5、14.5

54.5、59.5

92、95、98

09501791

19

1070、1100

1190、1190

14.5、15

52、54

90、93、96

09202206

19

1050、1100

1140、1200

13、15

54、55.5

87、95、98

09302015

19

1080、1120

1170、1190

14、15

55.0、55.0

100、104、104

09106064

19

925、940

1020、1030

16.5、17

63.5、65

109、110、115

09305927

19

1030、1030

1100、1110

15、15

58、59

69、68、61.5

09206305

19

1030、1040

1100、1110

14、14.5

50.5、59.5

70.558.5、58

09305926

19

1060、1070

1130、1130

15、16

57、58

98.5、96、98.5

09206304

19

810、920

915、995

15、17

55.5、67

163、172、176

09305925

19

1020、1030

1080、1100

14、15

58、58

114、118、93

YB/T5029-2006

≥795

965-1195

≥10

≥45

The test of preproduction axial fatigue

The acidleach macrostructure, General Loosen, center porosity, pattern segregation all less than 2 grades, has reached intended purposes.

Be 25MnV and 25MnVRE material composition contrast table below:

Can see that from last table novel material 25MnVRE has added Cr and two kinds of elements of RE than D level material 25MnV, the ratio of other element has also been done corresponding adjustment.Wherein, RE is the mixture of element lanthanum and cerium, and the remaining proportion of not annotating in the table all is a ferro element.

Be 25MnV and 25MnVRE material mechanical performance contrast table below

Can see that from last table the mechanical property of novel material 25MnVRE has has met or exceeded the mechanical property of HL type bar, for the mechanical property of clearer and more definite D level and HL section bar material, existing mechanical property example table with these 2 kinds of materials is as follows:

Model

Tensile strength

Yield-point

Elongation

Section shrinks

Fatigue strength

Impact

Rate (%)

60.2Mpa

The circulation cycle

A.K.V.J

The D type

793-965

≥620

≥10

≥50

≥590

The HL type

965-1195

793-862

≥12

45-50

≥795

≥1×10 ⁶

≥60.8

From then on table can see that the mechanical performance index that novel material 25MnVRE is done meets the requirement of HL section bar material fully.Stipulate the acidleach macrostructure among the GB GB10560-89:

1. in the test piece of steel cross section acidleach macrostructure macroscopic shrinkage cavity must not be arranged, bubble, crackle, be mingled with, skull patch and white point.

2. acidleach macrostructure rank should meet the following requirements:

	General Loosen	Center porosity	Pattern segregation
				The high-quality steel	≤ 3 grades	≤ 3 grades	≤ 3 grades
Senior high-quality steel	≤ 2 grades	≤ 2 grades	≤ 2 grades

25MnVRE steel sucker rod situ production processing step:

Incoming Quality Control (material composition, visual appearance and size)-head jumping-up moulding (equipment, horizontal forging machine 315-450T, heating in medium frequency stove 250KW, Heating temperature and soaking time are decided with product type)-body of rod magnetic spy (magnetic powder flaw detector)-(575KW cabinet-type electric furnace quenches, Heating temperature and soaking time are decided with product type)-water-cooled (swivel feeding mechanism automatically)-tempering (375KW cabinet-type electric furnace, hot temperature and soaking time are decided with product type)-machinery stretching (drawing-in machine)-cutting thread (automatic screw lathe)-packing (cleaning continuously, be coated with thread protector oil, wear the thread protector cap, dipping lacquer, packing)-warehouse-in.

Claims

1. super-strength sucker rod steel, it is characterized in that: the chemical ingredients of super-strength sucker rod steel is by weight percentage: carbon (C): 0.23-0.46%, silicon (Si): 0.1-0.3%, manganese (Mn): 1.25-1.55%, phosphorus (P):＜0.02%, sulphur (S):＜0.015%, vanadium (V): 0.05-0.15%, chromium (Cr): 0.025-0.032%, rare earth (RE): 0.05-0.13%, surplus is an iron, wherein: rare earth is the mixture of element lanthanum (La) and cerium (Ce), the tensile strength of described pumping rod is 1040-1080MPa, unit elongation is 14-14.5%, relative reduction in area is 53-59.5%, and impacting A.K.V is more than or equal to 84 joules.