SY/T 5374-2000 Methods of using pre-cementing fluid for oil and gas wells
Some standard content:
ICS 75.020
Registration No.: 8144—2001
Petroleum and Natural Gas Industry Standard of the People's Republic of ChinaSY/T 5374—2000
The application procedure of preflush for well cementing2000－12-12Published
State Administration of Petroleum and Chemical Industry
2001-06-01Implementation
SY/T 5374—2000
Cement pre-fluid for oil and gas wells is a special liquid used in cementing operations. It plays the role of isolating, buffering, flushing and diluting drilling fluid in the process of displacing drilling fluid, thereby improving the replacement efficiency of cement slurry and achieving the purpose of improving cementing quality. This revision supplements the content of drilling fluid flushing fluid, stipulates the relevant calculation and report format of drilling fluid flushing fluid; at the same time, according to the use of cement pre-fluid in various oil fields, the original standard SY/T5374-91 part of the text and text have been revised to make this standard applicable and operational.
From the date of entry into force, this standard will replace SY/T5374-91. Appendix A, Appendix B and Appendix C of this standard are all standard appendices. This standard is proposed by China Shishan Natural Gas Group Co., Ltd. This standard is under the jurisdiction of the Oil Drilling Engineering Professional Standardization Committee. This standard was drafted by: Daqing Petroleum Administration Bureau Drilling Production Technology Service Company, Drilling Research Institute: The main drafters of this standard are Tu Xiancheng, Zhou Jiman, Zhang Xianwu, Yang Zhiguang, and Xu Ming. This standard was first issued in July 1991, and this is the first revision. 1 Scope
Petroleum and Natural Gas Industry Standard of the People's Republic of China Application of Pre-flushing Fluid for Oil and Gas Well Cementing
The application procedurc of prcflush for well cementingSY/T5374—2000
S1/1 5374—91
This standard specifies the performance requirements, main indicators, compatibility test methods and designs of pre-flushing fluid for cementing. This standard is applicable to cementing, cement plugging and cementing operations in Shantou. The pre-flushing fluid in this standard includes flushing fluid and isolation fluid. 2 Cited standards
The clauses contained in the following standards constitute the clauses of this standard through reference in this standard. The versions shown in the publication of this standard are valid: All standards will be revised. The parties using this standard shall explore the possibility of using the latest versions of the following standards. GB10238-1998 Oil well cement
SY5546-92 Test method for door performance of oil and cement (confirmed in 2000)
3 Performance requirements
3.1 Flushing fluid
) It has a lower base fluid density and rheological properties close to Newtonian fluid: b) It has good penetration and suspension for loose mud and good thermal stability: () It reduces the viscosity and judgment of drilling fluid, has good dilution performance, has a lower critical return velocity of turbulence, and has good dilution and flushing effects on dark and casing; d) It has good effects on oil-based components in drilling fluid It has a wetting reversal effect: c) It has good compatibility with drilling fluid and cement slurry, and does not flash or thicken. It has little effect on the thickening time of cement slurry. It can add inert solid particles in an appropriate amount to improve the system effect. g) It does not corrode the casing.
) The flushing fluid should be selected with less influence on the strength of cement bonding. 3.2 Spacer fluid
) It has good compatibility with drilling fluid and cement slurry, which can reduce the viscosity and shear force of drilling fluid, and does not flash or thicken. It has little effect on the thickening time of water slurry filtration. 1) It has good suspension performance and heat High stability:
) The cold current isolation fluid has strong thixotropy, high dynamic plasticity, and good suspension displacement effect; {l) It has good wetting performance on the Shanji drilling fluid and isolation fluid, which is beneficial to improve the cement bonding strength:) Control the filtration loss and do not corrode the casing
3.3 Performance indicators
Performance indicators are shown in Appendix A (Appendix to the standard) 4: Compatibility test
Pre-fluid viscosity well fluid, cement slurry compatibility test is shown in Appendix B (Appendix to the standard) Approved by the State Bureau of Petroleum and Chemical Industry on December 12, 2000 001-06-01 Implementation
5 Design
5.1 Design basis and conditionswww.bzxz.net
SY/T5374—2000
a) Type, performance index and rheological parameters of drilling fluid for oil and gas wells; b) Type, performance index and rheological parameters of cement slurry in cementing design; c) Determine displacement flow pattern;
d) Well depth, temperature (wellhead and bottom hole circulation temperature, bottom hole static temperature), formation pore pressure, formation fracture pressure; e) Balance pressure calculation conditions determined by cementing design. 5.2 Usage
5.2.1 Conventional situation
a) Determine the critical velocity of turbulent flow based on rheological parameters and average geometric dimensions of the wellbore; b) Meet the flushing isolation contact time of not less than 4 minutes; c) When flushing fluid and isolation fluid are used at the same time, the total amount of pre-fluid shall comply with the provisions of b) in this article. 5.2.2 Special cases
a) When cementing small annulus and tail pipe, the amount of pre-fluid used is about 250m3 of annulus volume, and the minimum is not less than 1.6m3; b) When cementing large annulus, the amount of pre-fluid used is not less than 100m3 of annulus volume: c) For oil and gas wells with a depth of more than 3000m, 0.2~0.3m should be added for every additional 300m. 5.3 Rheological calculation
5.3.1 Based on the rheological calculation of cement slurry in cementing design, determine the appropriate pre-fluid type, measure the rheological parameters, check whether it meets the requirements of cementing rheological design, and make performance adjustments. 5.3.2 Determine the rheological mode based on the rheological performance parameters, and calculate the flow pressure drop, turbulence or plug flow of the annular pre-fluid. 5.3.3 The critical turbulence velocity of the flushing fluid is lower than the critical velocity of the cement slurry, and the critical plug flow velocity allowed by the isolation fluid is higher than the return velocity of the cement slurry plug flow displacement.
5.3.4 Verification of turbulent displacement equilibrium pressure conditions: Based on the critical velocity of cement slurry turbulence, calculate the total annular dynamic liquid column pressure (annular static liquid column pressure plus flow resistance) including drilling fluid, cement slurry, and pre-fluid, which should be less than the formation fracture pressure. 6 Calculation and report format related to drilling fluid flushing isolation effect Calculation and report format related to drilling fluid flushing isolation effect See Appendix C (Standard Appendix). Flushing fluid
SY/T5374—2000
Appendix A
(Standard Appendix)
Main performance indicators of pre-fluid
Base fluid density range: 1.0~1.03g/cm3. A1.2 Critical return velocity of flow: 0.3~0.5m/sc
A1.3 Thermal stability: Under cyclic temperature conditions, after 10h aging test, the performance change does not exceed 10%. A1.4 Flushing rate: The flushing rate of drilling fluid is more than 95%. A2
Isolation fluid
A2.1Density adjustable range: 1.08~2.40g/cmA2.2At the bottom hole circulation temperature, the dynamic plastic ratio is 0.05~0.12. A2.3Filtration loss standard:
a) At a temperature of 27~103℃ and a pressure difference of 7MPa, the 30min filtration loss is less than 250ml; b) At a temperature greater than 103 and a pressure difference of 7MPa, the 30min filtration loss should be less than 150ml. A2.4Good high temperature thermal stability.
The compatibility thickening time is not less than the cement slurry thickening time. B1 Compatibility test purpose
SY/T 5374—2H00
Attachment B
(Appendix of the standard)
Compatibility test of pre-pad fluid with drilling fluid and cement slurry Understand and master the performance changes of pre-pad fluid, drilling fluid and cement slurry in contact and mixing, as well as the uniformity and stability of the mixture. Drilling fluid performance changes refer to rheology, filtration loss: Cement slurry performance changes refer to rheology, filtration loss, curing time and compressive strength: 82 Test content
a) Effect of pre-pad fluid on rheological compatibility (pre-pad fluid and drilling fluid, cement slurry); b) Effect of pre-pad fluid on curing time (pre-pad fluid and cement slurry); c) Effect of pre-pad fluid on compressive strength (pre-pad fluid and cement slurry); d) Effect of pre-pad fluid on filtration loss (pre-pad fluid, drilling fluid and cement slurry) Note: The following test methods are the same for flushing fluid and isolation foot. The term "pre-fluid" below refers to the above two fluids. B3 Test procedures and methods
B3.1 Base fluid preparation
a) Pre-fluid: Prepared according to the product technical instructions and aged; 1) Drilling fluid: Sampled on site and fully mixed: () Cement slurry: Prepared from cement and slurry water on site. B3.2 Preparation of mixed fluids
The mixed fluids prepared in this chapter should be subjected to rheological properties, thickening time, repellency and water loss tests. Before preparing the fluids, the basic fluid data should be measured first. All mixed fluids in this chapter are expressed as the volume fraction of the entire mixed fluid, and the volume of the mixed fluid should meet the experimental requirements.
B3.3 Rheological properties
The rheological properties tests of cement slurry/drilling fluid, cement slurry/preflush fluid and drilling lift fluid/preflush fluid should be carried out. For each fluid combination, the recommended ratios are 95/5, 75/25, 50/50, 2575 and 5/95, and the drilling fluid/preflush fluid/cement slurry ratio of 25/50/25 is as follows: the measured data are recorded in Table B1: 83.4 Effect of forefill fluid on thickening time
The cement slurry mixed with 5%, 25% and 501% forefill fluid was subjected to thickening time test in accordance with GB10238, and compared with the thickening time data of cement slurry not mixed with forefill fluid; the measured data are recorded in Table B2. B3.5 Effect of forefill fluid on compressive strength
Cement samples containing 5%, 25% and 50% forefill fluid were measured. All samples should be selected at the bottom static temperature, and the compressive strength test was carried out in accordance with G11038, and compared with the compressive strength of cement samples without preflush fluid. B3.6 Effect of pre-fluid on cement slurry filtration loss Fire water test was carried out on cement slurry mixtures mixed with 5%, 25% and 50% pre-fluid according to SY5546: B4 Effect of suspension capacity test
) Mixing scheme: Volume fractions are: 5% liquid + 95% pre-fluid:
5% pre-fluid + 95% cement slurry.
SY/F 5374-2000
b) Stir the mixed liquid with a rod (then heat it to the full circulation temperature) and observe the viscosity change to see if there is any crystallization or other signs of premature coagulation. Table B1 Rheological compatibility data of drilling fluid, cement slurry and pre-pad fluid Cement slurry
Pre-pad fluid
Drilling fluid
Mixed fluid (volume fraction)
100 cement slurry
100% spacer fluid
100% drilling fluid
95% drilling fluid + 5% cement slurry
75% drilling fluid125% cement slurry
50% drilling fluid + 50% cement slurry
25% non-drilling fluid175% cement slurry||tt ||5% drilling fluid + 95%, cement slurry
95% drilling fluid 15% pre-feed fluid
75% drilling fluid←25% pre-feed fluid
50% drilling fluid 150% pre-feed fluid
25% drilling fluid + 75% pre-feed fluid
5% drilling fluid + 95% pre-feed fluid
95% cement slurry + 5% pre-feed fluid
75% cement slurry + 25% pre-feed fluid
50% water slurry 50 pre-feed fluid
25 water filter slurry + 75% pre-feed fluid
5% cement slurry "95% pre-feed fluid
25% drilling fluid - 5% pre-feed fluid
25 cement slurry
Mixed Mixture (volume fraction)
100% cement slurry
5% pre-fill liquid95% cement slurry
25% pre-fill liquid + 75% cement slurry
50% pre-fill liquid + 50% cement slurry
Test temperature
Viscometer dial reading
300200:0060
Table 2 Effect of pre-fill liquid on thickening time
Reading
Plastic viscosity
Thickening time
Yield value
C1 Test procedure
SY/T5374—2000
Appendix C
(Appendix to the standard)
Drilling Calculation and report format related to the effect of well fluid flushing and isolation CI.1 Wash, wipe and weigh the circular mold of the simulated casing in the flushing device. C1.2 Immerse the circular mold of the simulated casing in the drilling fluid for 10 cm, place it for 1min, then take it out, let it stand in the air for 1min, and then weigh it again.
C1.3 Put the circular mold with drilling fluid into the device containing flushing fluid, flush it for 5min at a speed of 1400r/min, then take out the circular mold, place it in the air for 1min, and weigh it.
Calculation of flushing rate
The flushing rate is calculated according to formula (C1):
Wu Zhong: A——Flushing rate, %;
Gn-Original mold mass, g:
× 100
Gi - Go
G)--Total mass of the mold after being immersed in the drilling fluid, g; G2--Total mass of the mold after flushing the adhering drilling fluid with flushing fluid, g. C3
Flushing rate test report format
Flushing rate test report format see Table C1:
Table CI flushing fluid test report format
Flushing rate A3Put the round mold with drilling fluid into the device containing flushing fluid, flush for 5 minutes at a speed of 1400r/min, take out the round mold, place it in the air for 1 minute, weigh it, and calculate the flushing rate. The flushing rate is calculated according to formula (C1): A——Flushing rate, %; Gn-Original mold mass, g: × 100; G2——Total mass of the mold after being immersed in drilling fluid, g; C3 Flushing rate test report format Flushing rate test report format is shown in Table C1: Table CI Flushing fluid test report format Flushing rate A3Put the round mold with drilling fluid into the device containing flushing fluid, flush for 5 minutes at a speed of 1400r/min, take out the round mold, place it in the air for 1 minute, weigh it, and calculate the flushing rate. The flushing rate is calculated according to formula (C1): A——Flushing rate, %; Gn-Original mold mass, g: × 100; G2——Total mass of the mold after being immersed in drilling fluid, g; C3 Flushing rate test report format Flushing rate test report format is shown in Table C1: Table CI Flushing fluid test report format Flushing rate A
Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.