Some standard content:
ICS 75.180.10
Request number: 4045-1999
Petroleum and natural gas industry standard of the People's Republic of ChinaSY/T 50241999
Bow-spring casing centralizer
Bow-spring casing centralizer:1999-08-(9 Issued
State Administration of Petroleum and Chemical Industry
2000-04-01 Implementation
SY/T 5024-1999
API Foreword
References
Test Equipment
Starting Force and Lowering Force Test Procedure
Resettling Force Test
9 Recommended Practice for Estimating Required Resettling Force in Deviated and Dogleg Wells Appendix A (Standard Appendix) Other Information
Appendix B (Difficult Appendix) Recommended Practice for Stop Ring Test Procedure Appendix C (Suggestive Appendix) Conversion of Imperial Units to International Units
SY/TS024—1999
This standard is a revision of SY5024-93 (Bumper Stabiliser) based on API Spec 10D (Specification for Bow Spring Casing Centralizers) (5th Edition, 1995). This standard is equivalent to API Spec [OD in terms of technical content and writing specifications. API Spec 10D 5th Edition is based on API Spec 10D (Specification for Bow Spring Casing Centralizers) (5th Edition, 1995). 10) (1991) 4th edition and ISO 10427:1993.
The black italic words and AP[added contents in the ISO version are in notes or shaded parts, and no mark is made after revision: Since this standard is equivalent to API Spec 1UI), there are the following differences between the revised standard and SY 5024-93:
1. Some technical notes are eliminated;
2. The recommended practice for using centralizers under special working conditions is added; 3. The test procedure for stoppers is added:
4. The conversion relationship between international units and British units is added, and the types and codes, wellbore size technical requirements and inspection rules in SY 5024-93 are removed.
This standard replaces SY5024-93 from the date of entry into force. Appendix A and Appendix B of this standard are both standard appendices. Appendix C of this standard is a prompt appendix.
This standard is proposed and coordinated by the National Technical Committee for Petroleum Drilling and Production Equipment and Equipment Standardization. The drafting unit of this standard is the Fourth Petroleum Machinery Factory of Jianghan Petroleum Administration Bureau. The main drafters of this standard are Guiquan and Li Li
SY/r5024-1999
API Foreword 1)
API Spcc:10D is the basic version of ISO10427:1993. This standard consists of two complete versions of API and ISO: The differences between the API version and the ISO version are as follows: · ISO10427:1993 does not have a policy statement and foreword. · The shaded parts in the text do not belong to ISO10427:1993. · Appendix B does not show the content of ISO10427:1993. - Appendix C does not belong to the content of API Spcc 10D. Terms that are unique to the ISO version are indicated in bold italics in the text, and here they are extended to be marked below the clauses by annotation. Terms that are unique to the API version are indicated in this standard by annotations below the clauses or by shading. The dashed parts of the standard text published this time are different from the previous API version. This standard is valid until the date printed on the cover, but can be used arbitrarily from the date the standard is obtained. 1) 15010427:1993 In particular: 1 Specification
Petroleum and Natural Gas Industry Standard of the People's Republic of China Bow- spring casing centralizers
Bow- spring casing centralizersSY/T 5024—1999
Replaces SY5024—93
This standard mainly sets out the minimum performance parameters, test procedures and marking methods for bow-spring casing centralizers. These requirements are limited, but sufficient to meet the needs of on-site cementing operations. The performance parameters of the bow spring centralizers contained in this standard are obtained under the prescribed test procedures. The test methods are applicable to:
a) Check and verify the design, material and process specifications of the manufacturer; b) Regular inspection to ensure the consistency of product performance parameters. This standard does not apply to rigid or solid centralizers. This standard also includes test equipment and marking requirements. In addition, a method for calculating the spacing of centralizers in inclined straight and dogleg wells based on the performance parameters and deviation of the centralizer is provided. 2 Reference standards
The provisions contained in the following standards constitute the provisions of this standard through reference in this standard. At the time of publication of this standard, the versions shown are valid. All standards will be revised, and the parties using this standard should discuss the possibility of using the latest versions of the following standards. SY/T 6194—1996 Casing and arm
3 Definitions
This standard adopts the following definitions.
3.1 Annular space when the casing is completely centered
The diameter of the eye minus the outer diameter of the casing divided by n
3.2 Permanent deformation of the centralizer
Refers to the change in the height of the bow of the centralizer after the bow spring is repeatedly bent. This standard stipulates that the centralizer is considered to have reached permanent deformation after being repeatedly bent [2 times.
3.3 Deflection or sag
Casing supported between two points will inevitably produce weight between the support points. This sag is called the sag of the casing or the deflection of the casing: the point at which the deflection is maximum is called the sag point (see Figure 4). 3.4 Dogleg severity
Rate of change of inclination, expressed in degrees per 30.5 m (100 ft) of deflection [see equation (31) in 9.12]. 3.5 Deflection
A bow spring is considered to be deflected when a force of three times the specified minimum return force (±5%) is applied to the bow spring. 3.6 Clamping device
A device for fixing a stop ring or a quick straightener to the casing. Clamping devices include screws, pawls, mechanical clamps, and epoxy resins. 3.7 Clamping force
The maximum force required to cause the stop ring to slip on the casing. 3.8 Wellbore size
Approved by the State Administration of Petroleum and Chemical Industry on September 9, 1999, 2000-04-01 Implementation
and eye diameter.
3.9 Limit
i.e. stop ring.
3.10 Reset force
SY/T 5024-1999
The force applied by the centralizer on the casing to keep the casing away from the wellbore wall. 3.11 Rigid centralizer
The limbs of the centralizer cannot be deflected and their diameter is a constant value (see rigid centralizer). 3.12 Lower
The maximum force required to move the centralizer on the casing. Note: The values of the starting force, reset force and lowering force may vary with the installation method. 3.13 Sliding force range
The range of force required to continue moving the stop ring after overcoming the clamping force. 3.14 Rigid centralizer
With ribs that cannot be deflected 3.15 Deviation clearance
The minimum distance between the eye diameter and the outer diameter of the casing. 3.16 Deviation clearance ratio
The ratio of the deviation clearance to the annular space, expressed as a percentage (see calculation example in Appendix A (Appendix A) of the standard). 3.17 Starting force
The minimum force required to get the centralizer into the casing. , force. 3.18 Stopper
A device placed on the casing to prevent the casing stopper from moving. The device can be used as a separate component or combined with the centralizer to form a component.
4 Requirements
4.1 Function of the centralizer
The function of the casing centralizer is sufficient to make the casing easy to lower to the predetermined well depth and to promote the casing to be centered in the wellbore. The centralizer can be composed of bow spring sheets of different types, shapes and different numbers. 4.2 Starting force| |tt||The maximum starting force shall be less than the weight of a 12.19 m (40 ft) long medium-walled casing (see Table 1). The maximum starting force shall be determined using a newly assembled centralizer.
4.3 Resetting force
The minimum resetting force required for the centralizer to achieve a deviation clearance ratio of 67% shall not be less than the value specified in Table 1. The method for determining and calculating the minimum resetting force is shown in Appendix A (Standard Appendix), 4.4 Test frequency
4.4.1 At least 6 newly assembled centralizers shall be used for necessary tests to verify and check the reliability and rationality of their design and process. The performance parameters of all tested centralizers must meet the requirements of Table 1. 4.4.2 In order to verify the consistency of product performance parameters, each specification of centralizer produced in accordance with this standard shall be tested at least once a year if the annual output exceeds 500. If the tested centralizer does not meet the performance parameter requirements in Table 1, corrective measures must be taken for the centralizer of the specification with problems and records shall be made. Irm
Casing Specifications
SY/T 50241999
Medium Wall Thickness Casing
Casing Centralizer Specifications
Minimum Reset Force at 67% Deviation
Maximum Starting Force
10 853
Note: The starting force and reset force specifications of the spring centralizer are obtained based on the centralizer installation method recommended by each manufacturer and the method of using a bump in the pipe inspection. When the centralizer is installed on the casing joint and the stop ring with an integral stop ring during the test, the actual results obtained are different from those obtained by the test method specified in the standard. Note that during the test, the report should indicate how the installation method and the type of device used should be noted. If the centralizer is tested by a method other than that specified in this standard, it is considered not a standard test and the test results may or may not meet the data in Table 1 and the quality of the liner gauge and flat head pipe regularity. 5 Test equipment
Test bench
The test bench shall be able to apply vertical loads and measure loads and vertical displacements. Examples of equipment are shown in Figures 1 and 2. 5.2 Test instrument
Displacement scale: The test bench shall be equipped with a displacement scale with a reading equal to or less than 1.6mm (1/16in) scale. 5.3 Test accuracy
5.3.1 Load measurement: The measurement accuracy shall be within 5% of the measured value. 5.3.2 Displacement: The accuracy within the measurement range shall be within 0.8mun (1/32in). 5.3.3 All test equipment must be calibrated once a year. 5.4 Test pipe
Inner pipe (A in Figures 1 and 2): The length of the inner pipe should be greater than the length of the centralizer in the flexed state and the length of the outer pipe B. 5.4.1
The outer diameter of the inner pipe A should be within the small tolerance range of the non-thickened pipe in SYT6194. Surface burrs and similar defects should be removed. The end surface of the inner pipe A not covered by the centralizer and other test elements are not subject to the above provisions. 5.4.2 Outer pipe (B in Figures 1 and 2): The length of the outer pipe should be greater than the length of the centralizer bow spring in the flexed state. The inner diameter of the outer pipe3
SY/T 5024—1999
should be the borehole diameter size corresponding to the centralizer being designed. The tolerance should be within +3.2～-0.8mm (+1/8～-1/32in). Surface burrs and similar defects should be removed. The upper end of the outer tube used for testing the starting force may be chamfered at the inner hole at an angle of up to 45°, with the maximum diameter of the chamfer not exceeding 3.2um (1/8in) of the inner diameter of the tube.
When testing the resetting force, the end of the outer tube not covered by the centralizer (not the end used for testing the starting force) is not subject to the above restrictions. Casing less
Well scale
Figure! Example of Casing Centralizer Starting Force Test Equipment 6 Starting Force and Lowering Force Test Procedure
6.1 Starting Force Test
Figure 2 Example of Casing Centralizer Resetting Force Test Equipment 6.1.1 Install the newly assembled centralizer on the four evenly distributed gate blocks C of the inner tube A as shown in Figure 1, and the height of each gate block on the outer surface of the inner tube shall not exceed 6.4mm (1/4in). Note: There are many different ways to install the centralizer on the casing in the field. Therefore, the starting force and reset force values obtained with this procedure will not be the same for all types of clamping devices. 6.1.2 The vertical deviation of the test assembly shall be within 5°. 6.1.3 Before the test, the contact surfaces shall be coated with petroleum-based grease. API modified grease is recommended, but other greases may also be used.
6.1.4 Place the stopper on the edge of the outer tube B, apply a load to the inner tube A, and pull the stopper into the outer tube B. 6.1.5 The load shall be recorded continuously from the beginning of the load application until the stopper is completely inserted into the outer tube B. 6.1.6 The starting force is equal to the maximum force required to move the inner tube A into the outer tube B (including the weight of the inner tube A and accessories). 6.2 Lowering force test
6.2.1 This test does not need to meet the maximum value, but it is still necessary to conduct the test and record the test results. 6.2.2
The lowering force test can be carried out simultaneously with the starting force test, or separately. Record the load from the moment the centralizer enters the outer tube B. 6.2.3
The lowering force is equal to the maximum force required to slide the inner kidney A in the outer tube B, and the force reading is taken as the time when it tends to stabilize (including the weight of the inner tube A and accessories). 6.2.4
7 Resetting force test
SY/T 5024—1999
7.1 During this test, the horizontal deviation between the inner tube A and the outer tube B shall be within 5 (see Figure 2). 7.2 The external force shall be applied to the outer tube B so that the force is transmitted vertically through the tube to the contacting device (see Figure 2). 7.3 Before collecting the test force data, all the springs shall be bent 12 times. 7.4 Apply the load and record the load-deflection readings. The minimum deflection change rate shall be recorded every 1.6 mm (1/16 in) increase. , until three times the minimum reset force (see Table 1) (±5%) is obtained. For each test position, the travel distance when 67% deviation interval ratio is obtained shall be measured.
7.5 Repeat the above test process until each spring bank and each group of springs of the centralizer are tested according to position I and position II shown in Figure 3.
7.6 Calculate the total load for each deflection. The weight of the outer tube and accessories should be added in the calculation. 7.7 Make a calculation based on the average value of the load under the corresponding degree and deflection. Load-deflection curve, from which the reset force at 67% deviation gap ratio is found [see Appendix A (Standard Appendix)]. Position 1
8 Marking
Figure 3 Test position of casing straightener
8.1 Casing straighteners that comply with this standard shall be marked by the manufacturer as follows. Position cover 1
There is no restriction on additional markings required by the manufacturer and the purchaser. The marking shall be made by stamping or template painting. The marking shall be marked on the coupling or bow spring leaf
8.2 Marking order:
a) Centralizer specification: The centralizer specification should be marked as the outer diameter of the casing to which the centralizer is installed; b) Hole size: The borehole size tested according to this standard should be marked;) For the assembled centralizer shipped, its size can be marked on a bow spring sheet or coupling. For the disassembled centralizer shipped or the bow spring sheet and coupling shipped separately, the identification symbol of each component that complies with this standard should be separately noted on the shipping list; d) Marking example: a 140mm (52 Displacement: The accuracy within the measurement range should be within 0.8 mun (1/32 in). 5.3.3 All test equipment must be calibrated once a year. 5.4 Test pipe
Inner pipe (A in Figures 1 and 2): The length of the inner pipe should be greater than the length of the centralizer in the flexed state and the length of the outer pipe B. 5.4.1
The outer diameter of the inner pipe A should be within the small tolerance range of the non-thickened pipe in SYT6194. Surface burrs and similar defects should be removed. The end surface of the inner pipe A not covered by the centralizer and other test elements are not subject to the above regulations. 5.4.2 Outer pipe (B in Figures 1 and 2): The length of the outer pipe should be greater than the length of the centralizer bow spring in the flexed state. The inner diameter of the outer pipe 3
SY/T 5024—1999
should be the borehole diameter size corresponding to the designed centralizer. The tolerance shall be within +3.2～-0.8mm（+1/8～-1/32in）. Surface burrs and similar defects shall be removed. The upper end of the outer tube used for testing the starting force may be chamfered at the inner hole at an angle of up to 45°, and the maximum diameter of the chamfer shall not exceed 3.2um（1/8in）of the inner diameter of the tube.
When testing the resetting force, the end of the outer tube not covered by the centralizer (not the end used for testing the starting force) is not subject to the above restrictions. Casing less
Well ruler
Figure! Example of the starting force test equipment for casing centralizer 6 Starting force and lowering force test procedures
6.1 Starting force test
Figure 2 Example of the resetting force test equipment for casing centralizer 6.1.1 Install the newly assembled centralizers on four evenly distributed gate blocks C of the inner tube A as shown in Figure 1, and the height of each gate block on the outer surface of the inner tube shall not exceed 6.4mm（1/4in）. Note: There are many different ways to install the centralizer on the casing in the field. Therefore, the starting force and reset force values obtained using this procedure will not be the same for all types of clamping devices. 6.1.2 The vertical deviation of the test assembly shall be within 5°. 6.1.3 Before testing, the contact surfaces shall be coated with petroleum-based grease. API modified grease is recommended, but other greases may be used.
6.1.4 Place the centralizer on the edge of the outer tube B, apply a load to the inner tube A, and pull the centralizer into the outer tube B. 6.1.5 The load should be recorded continuously from the beginning of the load application until the centralizer is completely inserted into the outer tube B. 6.1.6 The starting force is equal to the maximum force required to push the inner tube A into the outer tube B (including the weight of the inner tube A and accessories). 6.2 Lowering force test
6.2.1 This test does not need to meet the maximum value, but it should still be performed and the test results recorded. 6.2.2
The lowering force test can be carried out simultaneously with the starting force test, or separately. Record the load from the moment the centralizer enters the outer tube B. 6.2.3
The lowering force is equal to the maximum force required to slide the inner kidney A in the outer tube B, and the force reading is taken as the time when it tends to stabilize (including the weight of the inner tube A and accessories). 6.2.4
7 Resetting force test
SY/T 5024—1999
7.1 During this test, the horizontal deviation between the inner tube A and the outer tube B shall be within 5 (see Figure 2). 7.2 The external force shall be applied to the outer tube B so that the force is transmitted vertically through the tube to the contacting device (see Figure 2). 7.3 Before collecting the test force data, all the springs shall be bent 12 times. 7.4 Apply the load and record the load-deflection readings. The minimum deflection change rate shall be recorded every 1.6 mm (1/16 in) increase. , until three times the minimum reset force (see Table 1) (±5%) is obtained. For each test position, the travel distance when 67% deviation interval ratio is obtained shall be measured.
7.5 Repeat the above test process until each spring bank and each group of springs of the centralizer are tested according to position I and position II shown in Figure 3.
7.6 Calculate the total load for each deflection. The weight of the outer tube and accessories should be added in the calculation. 7.7 Make a calculation based on the average value of the load under the corresponding degree and deflection. Load-deflection curve, from which the reset force at 67% deviation gap ratio is found [see Appendix A (Standard Appendix)]. Position 1
8 Marking
Figure 3 Test position of casing straightener
8.1 Casing straighteners that comply with this standard shall be marked by the manufacturer as follows. Position cover 1
There is no restriction on additional markings required by the manufacturer and the purchaser. The marking shall be made by stamping or template painting. The marking shall be marked on the coupling or bow spring leaf
8.2 Marking order:
a) Centralizer specification: The centralizer specification should be marked as the outer diameter of the casing to which the centralizer is installed; b) Hole size: The borehole size tested according to this standard should be marked;) For the assembled centralizer shipped, its size can be marked on a bow spring sheet or coupling. For the disassembled centralizer shipped or the bow spring sheet and coupling shipped separately, the identification symbol of each component that complies with this standard should be separately noted on the shipping list; d) Marking example: a 140mm (52 Displacement: The accuracy within the measurement range should be within 0.8 mun (1/32 in). 5.3.3 All test equipment must be calibrated once a year. 5.4 Test pipe
Inner pipe (A in Figures 1 and 2): The length of the inner pipe should be greater than the length of the centralizer in the flexed state and the length of the outer pipe B. 5.4.1
The outer diameter of the inner pipe A should be within the small tolerance range of the non-thickened pipe in SYT6194. Surface burrs and similar defects should be removed. The end surface of the inner pipe A not covered by the centralizer and other test elements are not subject to the above regulations. 5.4.2 Outer pipe (B in Figures 1 and 2): The length of the outer pipe should be greater than the length of the centralizer bow spring in the flexed state. The inner diameter of the outer pipe 3
SY/T 5024—1999
should be the borehole diameter size corresponding to the designed centralizer. The tolerance shall be within +3.2～-0.8mm（+1/8～-1/32in）. Surface burrs and similar defects shall be removed. The upper end of the outer tube used for testing the starting force may be chamfered at the inner hole at an angle of up to 45°, and the maximum diameter of the chamfer shall not exceed 3.2um（1/8in）of the inner diameter of the tube.
When testing the resetting force, the end of the outer tube not covered by the centralizer (not the end used for testing the starting force) is not subject to the above restrictions. Casing less
Well ruler
Figure! Example of the starting force test equipment for casing centralizer 6 Starting force and lowering force test procedures
6.1 Starting force test
Figure 2 Example of the resetting force test equipment for casing centralizer 6.1.1 Install the newly assembled centralizers on four evenly distributed gate blocks C of the inner tube A as shown in Figure 1, and the height of each gate block on the outer surface of the inner tube shall not exceed 6.4mm（1/4in）. Note: There are many different ways to install the centralizer on the casing in the field. Therefore, the starting force and reset force values obtained using this procedure will not be the same for all types of clamping devices. 6.1.2 The vertical deviation of the test assembly shall be within 5°. 6.1.3 Before testing, the contact surfaces shall be coated with petroleum-based grease. API modified grease is recommended, but other greases may be used.
6.1.4 Place the centralizer on the edge of the outer tube B, apply a load to the inner tube A, and pull the centralizer into the outer tube B. 6.1.5 The load should be recorded continuously from the beginning of the load application until the centralizer is completely inserted into the outer tube B. 6.1.6 The starting force is equal to the maximum force required to push the inner tube A into the outer tube B (including the weight of the inner tube A and accessories). 6.2 Lowering force test
6.2.1 This test does not need to meet the maximum value, but it should still be performed and the test results recorded. 6.2.2
The lowering force test can be carried out simultaneously with the starting force test, or separately. Record the load from the moment the centralizer enters the outer tube B. 6.2.3
The lowering force is equal to the maximum force required to slide the inner kidney A in the outer tube B, and the force reading is taken as the time when it tends to stabilize (including the weight of the inner tube A and accessories). 6.2.4
7 Resetting force test
SY/T 5024—1999
7.1 During this test, the horizontal deviation between the inner tube A and the outer tube B shall be within 5 (see Figure 2). 7.2 The external force shall be applied to the outer tube B so that the force is transmitted vertically through the tube to the contacting device (see Figure 2). 7.3 Before collecting the test force data, all the springs shall be bent 12 times. 7.4 Apply the load and record the load-deflection readings. The minimum deflection change rate shall be recorded every 1.6 mm (1/16 in) increase. , until three times the minimum reset force (see Table 1) (±5%) is obtained. For each test position, the travel distance when 67% deviation interval ratio is obtained shall be measured.
7.5 Repeat the above test process until each spring bank and each group of springs of the centralizer are tested according to position I and position II shown in Figure 3.
7.6 Calculate the total load for each deflection. The weight of the outer tube and accessories should be added in the calculation. 7.7 Make a calculation based on the average value of the load under the corresponding degree and deflection. Load-deflection curve, from which the reset force at 67% deviation gap ratio is found [see Appendix A (Standard Appendix)]. Position 1
8 Marking bzxZ.net
Figure 3 Test position of casing straightener
8.1 Casing straighteners that comply with this standard shall be marked by the manufacturer as follows. Position cover 1
There is no restriction on additional markings required by the manufacturer and the purchaser. The marking shall be made by stamping or template painting. The marking shall be marked on the coupling or bow spring leaf
8.2 Marking order:
a) Centralizer specification: The centralizer specification should be marked as the outer diameter of the casing to which the centralizer is installed; b) Hole size: The borehole size tested according to this standard should be marked;) For the assembled centralizer shipped, its size can be marked on a bow spring sheet or coupling. For the disassembled centralizer shipped or the bow spring sheet and coupling shipped separately, the identification symbol of each component that complies with this standard should be separately noted on the shipping list; d) Marking example: a 140mm (55 Repeat the above test process until each spring bank and each group of springs of the centralizer have been tested in position I and position II as shown in Figure 3.
7.6 Calculate the total load for each deflection. The gravity of the outer tube and accessories should be added in the calculation. 7.7 Draw a load-deflection curve based on the approximate mean value of the load under the corresponding deflection, and find the reset force at 67% deviation gap ratio from the curve [see Appendix A (Standard Appendix)]. Position 1
8 Marking
Figure 3 Test position of casing centralizer
8.1 Casing centralizers that comply with this standard should be marked by the manufacturer in accordance with the following provisions. Position cover 1
There is no restriction on additional markings required by the manufacturer and the purchaser. The marking should be made by stamping or template painting. The marking should Marked on the coupling or bow spring piece.
8.2 Marking order:
a) Centralizer specification: The centralizer specification should be marked as the outer diameter of the casing to install the centralizer; b) Hole size: The hole size tested according to this standard should be marked;) The size of the assembled centralizer can be marked on a bow spring piece or coupling. For the disassembled centralizer or bow spring piece and coupling shipped separately, the identification symbol of each component in accordance with this standard should be separately indicated on the shipping list; d) Marking example: a 140mm (55 Repeat the above test process until each spring bank and each group of springs of the centralizer have been tested in position I and position II as shown in Figure 3.
7.6 Calculate the total load for each deflection. The gravity of the outer tube and accessories should be added in the calculation. 7.7 Draw a load-deflection curve based on the approximate mean value of the load under the corresponding deflection, and find the reset force at 67% deviation gap ratio from the curve [see Appendix A (Standard Appendix)]. Position 1
8 Marking
Figure 3 Test position of casing centralizer
8.1 Casing centralizers that comply with this standard should be marked by the manufacturer in accordance with the following provisions. Position cover 1
There is no restriction on additional markings required by the manufacturer and the purchaser. The marking should be made by stamping or template painting. The marking should Marked on the coupling or bow spring piece.
8.2 Marking order:
a) Centralizer specification: The centralizer specification should be marked as the outer diameter of the casing to install the centralizer; b) Hole size: The hole size tested according to this standard should be marked;) The size of the assembled centralizer can be marked on a bow spring piece or coupling. For the disassembled centralizer or bow spring piece and coupling shipped separately, the identification symbol of each component in accordance with this standard should be separately indicated on the shipping list; d) Marking example: a 140mm (5
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