CN1045112C - Heat-resistant steel wire for logging - Google Patents

Abstract

The present invention relates to a heat-resistant well logging steel wire. Vanadium as an alloy element is added in silicon-manganese high-carbon steel, and the steel wire comprises 0.72 to 0.78% of C, 1.2 to 1.5% of Si, 0.6 to 0.9% of Mn, 0.04 to 0.06% of V, at most 0.03% of P, at most 0.03% of S and balance of Fe. The heat-resistant well logging steel wire has the advantages of simple production technology, small content of alloy elements, low cost and stable performance; the heat-resistant well logging steel wire is suitable for the situations in China and can be popularized and applied in large areas.

Description

Heat-resistant steel wire for logging

The present invention relates to contain the steel alloy of silicomanganese, a kind of heat-resistant steel wire for logging that is applicable to the thermal recovery oil well is provided especially.

In the crude production of China, the viscous crude ratio increases day by day, has reached 1,200 ten thousand tons/year at present, expects " eight or five " latter stage, will rise to 4000～5,000 ten thousand tons/year.And heavy crude producing need infiltrate steam, and envrionment temperature is elevated to about 300 ℃ as a result, at this moment adopts common steel wire for logging can not meet the demands, needs for solving field produces, once military project 906 stainless steels is made steel wire for logging, and is on probation on the thermal recovery oil well.Because this class steel wire costs an arm and a leg (80,000 yuan/ton), can't big area promote the use of.With the immediate technology of the present invention be the large steel wire rod of a kind of siliceous height (1%Si, 0.5%Mn, the 0.8%C) (WireJournalInternational1983 that Nippon Steel Corporation develops, July, 72), but it is as structural steel for building, the normal temperature better performances, resistance toheat is relatively poor.

The object of the present invention is to provide a kind of high-temperature behavior good and cost is low, the heat-resistant steel wire for logging that is applicable to the thermal recovery oil well of long service life.

The invention provides a kind of heat-resistant steel wire for logging, it is characterized in that: be added with the alloying element vanadium in silicomanganese high carbon steel, following (weight %) fills a prescription:

C Si Mn V P S Fe

0.72～0.78 1.2～1.5 0.6～0.9 0.04～0.06≤0.03≤0.03 surplus

Generally speaking, the microstructure of high-carbon steel wire is cold deformation sorbite tissue, thereby its intensity is decided by the sheet spacing and the work hardening capacity of ferritic intensity and lamellar pearlite.Perlite sheet spacing is littler often, intensity is higher, the adding of alloying element is just strengthened by ferrite and is changed the purpose that the perlite size realizes improving material capability, the increase of Si content, it mainly is the reinforced ferrite matrix, thereby the hot strength that improves steel is postponed its recrystallize softening process, because the atomic radius of Si is littler than Fe, after increasing Si content, can cause lattice distortion, increase the frictional force that dislocation is moved in ferrite, thereby relaxation, creep value are reduced, hot strength increases, and has alleviated the trend that age hardening becomes fragile.But after Si＞1.5%, because the variation of interface enthalpy can not be ignored, the sheet spacing will increase.Mn in the high carbon steel is brought up to 0.6～0.9% from 0.52%, than the hardened negative interaction, only can not play the effect of solution strengthening in the time of can not bringing strain during distortion because of the carbon atom contraposition that cementite decomposes out.The V of trace is at thinning microstructure, improve plasticity, drawing property is so that there is active effect aspects such as raising intensity, experimental result shows adding 0.04～0.06%V when improving Si content, room temperature, high temperature and creep rupture strength can be significantly improved, and plasticity, toughness still can be maintained to the desired level of high-carbon steel wire at this moment.Below by embodiment in detail the present invention is described in detail.

Embodiment:

The steel grade composition is listed in the W3 in the table 1, selects high carbon steel W1 and silicon manganese steel W2 to contrast simultaneously, and composition is all listed in table 1, and experimentation is as follows:

The melting in the 25kg vacuum induction furnace of test steel grade; under argon shield, pour into the 10kg steel ingot; adopt 1120 ℃ to open forging subsequently; 800 ℃ are stopped forging; be swaged into Φ 15 bars; reroll into Φ 10 vertical bars, carry out annealing softening and handle, its annealing process is: 1.5 hours stoves of 830 ℃ of insulations be chilled to 570 ℃ again air cooling come out of the stove.For preventing surface oxidation, decarburization, surperficial acute protective cover Ti3.Carry out phosphatization, saponification processing then.Adopt the drawing process of inviting time little tube reducing more, carry out work in-process processing.Its operational path is as follows:

Φ10→Φ9.4→Φ8.3→Φ7.81→Φ7.34→Φ6.9→Φ6.5→Φ6.2mm

Half-finished mechanical property is as shown in table 2:

Advanced quadrat is bathed and is quenched before the drawing of finished product steel wire, and its processing parameter is: the line temperature: 930 ℃; Plumbous overflowing: 570 ℃; Trace speed: 6.5 meters/minute.Wire drawing is carried out on 1/650 and 6/650 drawing wire machine, and its drawing process is:

Φ6.5→Φ6.2→Φ5.6→Φ5.0→Φ4.5→Φ4.07→Φ3.7→Φ8.36→Φ3.10→Φ2.87→Φ2.67→Φ2.5

From Φ 6.5 → Φ 2.5 overall compression ratios 85.2%

The finished product Mechanical Properties of Steel Wire is as shown in table 3:

Sample is heated to the excessive degree of test, is incubated and surveys its tensile property after ten minutes, the results are shown in table 4.

In order to simulate the test mode of thermal recovery well, carried out 7～10 days rupture test, and with the rupture test sample chamber of the doing tension test of overflowing of not rupturing, with examination after rupture test, the residual intensity of material.Rupture test the results are shown in Table 5.

The Chemical Composition of table 1 test materials (wt%)

Numbering	C	Si	Mn	P	S	Mo	V
								W1	0.82	0.27	0.58	0.006	0.020
W2	0.70	1.30	1.19	0.005	0.020
								W3	0.78	1.31	0.61	0.005	0.019		0.049

The half-finished mechanical property of table 2

Numbering	Diameter (mm)	Rupture pull force (KV)	Breaking tenacity (MPa)	Unit elongation (δ %)
					W1	6.5	40.2	1211	6.6
W2	6.25	40	1304	6.2
					W3	6.5	44.2	1382	7.4

Table 3 finished product Mechanical Properties of Steel Wire

Numbering	Steel grade	Maximum pull (KN)	Maximum stress (MPa)	360 ° are reversed (inferior)	180 ° of bendings (inferior)
						W1	Carbon steel	9.95	2027	23	9.5
W2	Silicon-manganese steel	9.95	2027	24.5	9.5
						W3	Silicon-vanadium steel	10.60	2159	23	9
The Q-ZG201-87 standard		7.79 9.45	1576 1913	≥21	≥7

The TRANSIENT HIGH TEMPERATURE intensity of table 4 finished product twine

Numbering	Steel grade	Test temperature (℃)	The high intensity (MPa) of irritating
				W1	Carbon steel	200	1863
309	1460
		350	1340
400	1174

Numbering	Steel grade	Test temperature (℃)	Hot strength (MPa)
				W2	Silicon manganese steel	200	1833
300	1610
		350	1430
400	1284

Numbering	Steel grade	Test temperature (℃)	The high intensity (MPa) of overflowing
				W3	The silicon vanadium steel	200	2023
300	1764
		350	1554
400	1380

Table 5 rupture test result

Numbering	Steel grade	Rupture time under 400 ℃ of 200kg load (hour)	Fracture time gating under 400 ℃ of 245kg load (hour)
				W1	Carbon steel	＞168	64.5； 64.5
W2	The Si-Mn steel	＞168	43；102.5；＞140
				W3	The Si-V steel	＞168	113.75；＞231

Utilize heat-resistant steel wire for logging product of the present invention respectively in the Liaohe River, the heavy crude heat extraction of Shengli Oil Field goes forward side by side and exercises with examination.To be on the safe side, 28 wells have at first been tried out at the normal temperature well below 100 ℃ in the Liaohe Oil Field, and then at 285～290 ℃, 180 meters dark hot holes use 16 wells, and the result is normal fully.Shengli Oil Field, test 27 wells of going into the well in the thermal recovery well of 228.6～344.1 ℃ of well depth 8707～930M, temperature stopped 36 hours 45 minutes.Then steel wire is pulled out with the mistake section and cut off, continue 27 wells on probation again, the back surplus 1000 meters shut down and scrap, this dish steel wire is at go into the well altogether 76 wells time of Shengli Oil Field hot hole, and the plain carbon stool steel wire uses after 5 times at the high-temp thermal recovery well, crooked straight value is just reduced to 5 times from 21 times, general 8～12 wells that use are just scrapped, and see that by contrast the work-ing life of heat-resistant steel wire for logging is more much longer than common steel wire for logging.

The present invention has following advantage in a word:

1. during the processing and manufacturing steel wire, can with reference to the smelting of high-carbon steel, rolling, drawing process, utilize the production of existing equipment tissue.

2. the service life the when heat-resistant steel wire for logging of being processed into is tested in thick oil thermal extraction is more much longer than common high-carbon steel steel wire for logging.

3. alloying element content is few, and cost is low, and stable performance is fit to China's national situation, can large scale application.

Claims (1)

1. heat-resistant steel wire for logging, it is characterized in that: be added with the alloying element vanadium in silicomanganese high carbon steel, following (weight %) fills a prescription:

C Si Mn V P S Fe

0.72～0.78 1.2～1.5 0.6～0.9 0.04～0.06≤0.03≤0.03 surplus