SY/T 0086-1995 Electrical insulation standard for cathodic protection pipelines
Some standard content:
Petroleum and Natural Gas Industry Standard of the People's Republic of China Electrical Insulation Standard for Cathodically Protected Pipelines SY/T 0086-95 Main unit: China Petroleum and Natural Gas Pipeline Survey and Design Institute Approving department China National Petroleum Corporation Petroleum Industry Press 1995 Beijing [General Principles]! Terminology
3 Insulation requirements
4 Insulation methods
41 General provisionsmt
42 Electrical insulation maintenance of pipelines
(12)
4.3 Electrical insulation of pipelines and other structures
4.4 Electrical insulation of pipelines and offshore platform risers4.5 Electrical insulation cables for pipeline ducts and power transmission lines5 Comparison of electrical insulation devices suitable for pipelines5.1 Types of available electrical insulation equipment
gu(14)
(lb)
5.2 Factors to be considered in selecting electrical insulation equipment53 Selection of electrical insulation device type
6 Requirements for electrical insulating devices
6.! General requirements
6.2 Insulation wire
6.3 Insulation device aam
7 Equipment installation
7.1 General use
72 Installation
p (17
n()
（18）
（18）
ammm/23)
High 2
7.4 Preparation for on-site test
3 On-site test and maintenance
8. General instructions
8.2 Field test
（27)
83 Test of branch insulation device
Maintenance 4 Maintenance
Appendix A Explanation of terms used in this specification
Additional instructionswww.bzxz.net
+（29
Appendix A Explanation of terms used in this specification|| tt||The words used to indicate the degree of strictness in the text of this specification are as follows: when implementing, they are treated differently according to the following instructions
(1) Words that indicate that it is very strict and must be done: positive words are "must be issued"; negative words are "strictly prohibited"
(2) Words that indicate that it is strict: under normal circumstances, it should be done: positive words are "should"
negative words are "should not" or "must not"(3) Words that indicate that there is a slight choice: when conditions permit, it should be done first, positive words are "should\" or "may"; negative words are "should not,
Additional instructions
|List of the editorial unit, participating units
and main drafters of this specification
Editorial unit: China Petroleum and Natural Gas Pipeline Survey and Design Institute Mengjia Unit: Tianjin University
Main drafters: Hu Shixin Yu Yiying Sun Zhengguo Meng Guangji Xu Kuai China National Petroleum Corporation Document
(95) CNPC Technical Supervision No. 156
Notice on the approval and release of eleven oil and gas industry standards including "Safety Regulations for Heating Furnaces for Petroleum Industry" To all relevant units:
Eleven standards (drafts) including "Safety Regulations for Heating Furnaces for Petroleum Industry" have been reviewed and approved The standards are approved as the oil and gas industry standards and are published. The numbers and names of the standards are as follows:
Serial number
1.SY003195
Safety regulations for heating furnaces used in the oil industry (replacing SYI31-88)
SY/T.0086-95Electrical insulation standard for open-pole protection pipelinesSY/T4074-95Copper pipeline cement mortar coating machine coating process
SY/T4075-95Copper pipeline fly ash cement mortar centrifugal molding construction process
SY/T4076-95 Copper pipeline liquid coating pneumatic extrusion process
SY/T4077-93 Steel pipeline cement mortar lining pneumatic extrusion process
Serial number
7SY/T4078-95 Steel pipeline internal coating liquid coating patching machine patching process
SY/T4079-95 Petroleum and natural gas pipe crossing project construction and acceptance specifications8
9.SY/T4080-95 Pipeline and reservoir leakage detection method10SY4081-95
Steel ball reservoir end seismic adjustment technical standard11SY/T4082-95 Gas field well site equipment and pipeline installation project construction and acceptance specifications The above standards shall be implemented from September 1, 1995. China National Petroleum Corporation. March 11, 1995. Preparation instructions. This standard is based on the guiding ideology of the notification of China National Petroleum Corporation (93) Zhongyoujiyu No. 52 and the professional standard system table of petroleum engineering construction design on the equivalent adoption of international standards and foreign advanced standards. It is written in accordance with the equivalent adoption of the American NACEERP-02-86 "Electrical Insulation of Cathodic Protection Pipelines". In the process of writing, the experience of using insulating flanges for long-distance pipelines was summarized, and at the same time, relevant foreign standards such as DIN.3389 were referred to: and combined with scientific research: NACE was analyzed. RP-02-86 proves that equivalence is feasible: widely solicited opinions from relevant scientific research, design, construction, management and colleges and universities, and repeatedly discussed the main issues in the standard: finally: after the China National Petroleum Corporation Planning and Design Institute organized relevant units to review and finalize the draft, the standard was written using advanced foreign standards. Due to lack of experience, it is inevitable that there are some shortcomings. In the process of implementing this standard, if you find that there are places that need to be modified and supplemented, please provide your opinions and relevant information to our institute: so that you can refer to it when revising it. China Petroleum and Natural Gas Pipeline Survey and Design Institute December 1994
L.0.1 In order to actively adopt new processes, new technologies, new equipment and new materials in the electrical insulation design of steel pipeline projects for transporting oil, gas and water, so as to achieve advanced technology, economic rationality and safety and applicability. To ensure quality, this standard is formulated. 1.0.2 This standard applies to the cathodic protection projects of newly built and expanded buried steel oil, gas and water delivery pipelines. It does not involve the requirements of insulating devices for purely safety purposes and is not applicable to pipelines that transport chemical media with special requirements. 1.0.3 In the electrical insulation design of cathodic protection pipelines, in addition to complying with this standard, the provisions of the current relevant national standards and specifications shall also be observed. 1.0.4 This standard only proposes the minimum requirements for the electrical insulation of cathodic protection pipelines, and does not exclude the use of better methods and materials than those specified in this standard. L.0.5 This standard is equivalent to NACEERP-02-86 "Electrical Insulation of Cathodic Protection Pipelines".
2 Terminology
2.0.1 Pipeline Electrical Insulation (Pipeline Ekectrical Isolation) is used in the sales channel. On the pipeline support structure, special electrical insulation devices are installed on the pipeline accessories to avoid the formation of metal or similar conductive paths in the pipeline and other metal structures.
2.0.2 Pure insulation devices (Lsolating/Insula(ing Devices) - The following equipment components (see 2.0.3-2.0.9 of this standard) are collectively referred to as pure insulation devices: they can be special accessories, customized processing parts or modifications of components in existing systems. 2.0.3 Isolating Coupling - Mechanical pipe joints used to provide permanent electrical insulation
2.0.4 Isolating flange (Isolating Flange) 2.0.5 Mechanical tapping insulator (LsolatingMechanialTappingSkeve) - a connector that can be installed in an existing pipeline: it is usually only suitable for low-pressure pipelines with small diameters or pressures below IMPa. 2.0.6 Insulating spool - an insulating device installed in pipelines that transport brine (brine) or other conductive fluids. 2.0.7 Insulating union + - a kind of live (pipe) joint with insulating materials:
2.0.8 Monobloc insulator joint - a factory-made, separate body with two insulating rings and (or) insulating gaskets, connected together by welding or with a root block fixing surface. This joint needs to be tested for electrical performance and working pressure, and cannot be disassembled after installation. 2.0.9 Prefabricated Isolating Joint: A pipe joint that provides electrical isolation between two pipe sections. This prefabricated isolating joint is a complete set of equipment manufactured and tested by the factory and can be quickly installed on the pipeline. It can be a preassembled insulated flange joint: This is usually not suitable for disassembly. 3 Electrical insulation requirements
3.0.1 The insulation device described in this standard is only used for cathodic protection: and the voltage applied to both sides of the insulation device under severe service conditions should not exceed 30V. 3.0.2 For all pipelines connected to devices or equipment that may come into contact with the soil or groundwater, the cathodic protection current may flow into the device or equipment. If it is not intended to protect the connected structure, unless certain protective measures are taken, the reported protection current will leak. Providing discontinuity or interrupting the connection between the metal or other conductive path between the pipeline and the device or equipment connected to it can prevent the cathodic protection current from flowing to the connected parts. 3.0.3 In order to solve the problem of current leakage, it is particularly important to use pipelines with good quality anti-corrosion insulation layers. Where an electrical insulation system is not provided, cathodic protection may become uneconomical or impossible. 3.0.4 Metallic contact between casing and material supply pipe may cause the protective current to flow away from the supply pipe and adjacent casing or pipe. 3.0.5 Although leakage is not obvious in concrete, preventing full contact between pipeline and large steel bars in the soil is an important aspect of electrical insulation. Generally, such contact will occur where the pipeline passes through a room or building wall. This contact can cause the protective current to flow to the steel bars. Therefore, when cathodic protection is used, it is impossible to force the pipe/ground potential at the contact point or its adjacent points to be consistent with the potential of the rest of the pipeline. 3.0.6 In areas involving dissimilar metal materials, the use of electrical insulation can reduce the potential of the pipe/ground to the same level as the rest of the pipeline. The effect is reduced to a minimum
3.0.7 When the pipeline itself maintains electrical continuity: and is supported by other metal structures in contact with the soil or groundwater, the same measures must be taken to make the pipeline electrically insulated from the supporting structure. These insulating supports must be prevented from damaging the pipeline cover and make it adaptable to the relative displacement of the pipeline, vibration and temperature difference. 3.0.8 When electric gates and similar components have become an integral part of the pipeline system. The grounding system of power and equipment is required to be electrically insulated: the electrical insulation measures taken must comply with the current provisions of relevant safety standards
3.0.9 In order to control or facilitate special testing. The cathode can be limited by electrical insulation To protect the current from flowing to the various sections of the pipeline system, it is sometimes possible to use an electrical control resistor across the insulation (or segmentation) device. 3.0.10 When two forms of cathodic protection (e.g., cathodic protection and forced current) are required on a pipeline, segmented electrical insulation can be used. 3.0.11 The use of electrical insulation in pipelines can help control or mitigate the effects of mixed currents, such as earth currents. Currents generated by electric traction systems, etc. 3.0.12 If the pipeline is carrying highly conductive liquids or slurries (e.g., salt water), special considerations should be given to the selection of insulation devices. Because significant current leakage may occur through the pipeline that transports liquids or slurries, this Similarly, if a device is installed in a low-voltage environment (soil or water) where there may be significant external current leakage, appropriate precautions must be taken. 3.13 Special insulation devices can be installed on the riser of the offshore structure to insulate the cathodic protection system of the pipe from the cathodic protection system of the platform casing structure. If there is a potential difference, this is necessary because (1) the type of cathodic protection system used is different (i.e., circulating current and forced current); (2) the current required for the pipeline and structure may be different (i.e., different materials or coatings are used); 3.0.14 When selecting the location for the insulation device, the mechanical forces acting on the insulation device should be considered. 3.15 Avoid installing insulation devices in enclosed areas where volatile gases may be present. 3.0.16 When insulation devices are installed at the end of a section of pipe protected by polarity, care should be taken to ensure that no corrosion is caused on the unprotected side of the insulation device: this can be controlled by installing anodes or zinc grounding electrodes on the unprotected side. 4 Electrical insulation methods. 4.1 General provisions. 4.1.1 Electrical insulation of equipment can be achieved by using purchased special devices, custom-made parts, or modifying components of existing equipment. The method used depends on the function to be achieved by the electrical insulation and its mechanical structure and the requirements of the equipment to be insulated. The insulation methods described below include the use of proprietary devices and standard parts suitable for insulation, and the preferred materials and methods are indicated for custom parts such as insulating joints.
4.2 Insulation of pipelines
4.2.1 Pipelines can be separated into discrete conductive sections by connecting insulating devices. The insulating device can be a combination of pre-installed or installed insulating materials or pipe joints on existing flanges.
4.2.1.1 Insulating flanges (see Figure 4.2.1-1) Existing flanges in the pipeline can be electrically isolated by inserting insulating gaskets between the two flanges. The insulating gaskets should have an outer diameter matching the flange and can be installed in the flange bolt distribution range or in the ring. The flange connection bolts should be insulated from the flange with insulating sleeves inserted into the bolt cylinder and insulating washers under the nuts. The insulating sleeves and washers can be combined into a single body, and the bolts can be insulated from only one flange. In this way, the cathodic protection applied to the pipeline also protects the bolts in the continuous flange installed underground or underwater. However, this will make the insulation performance test more difficult.
Sheng: This figure does not show the active skills to prevent the flow of gas (see 7.2.5.3 of this standard). In addition, the (heart) source gasket can be replaced with an integral type: (2) It can also be used only in one to the insulated type (some car standards 42.1.1) 4.2.1.2 Pre-assembled insulating flange. The insulating flange can be pre-assembled and provided with a threaded or weldable short pipe for connecting to the pipeline on site. 4.2.1.3 Pre-assembled insulating joints,
(1) High-pressure integral insulating joints. The lifting head with a pressure higher than 1.0MP% (see Figure 4.2.2) consists of two short sections with flanges and a non-load-bearing ring. The load ring and a rectangular pipe
tighten the seam of the palm
deep country products
real country parts of the palm
type fat spicy dense whole piece
mouth type electric green seal hot shop
twist tender basket
Figure 4.21-Typical flame-proof flange
ground##place
pure wedding ring
Figure 4.21-2 Integral health joint (high voltage) The joint is overlapped between the inner surface of the load ring and the outer surface of the rectangular joint. A resin seal that can both seal and insulate is used. The two short joints and the destruction ring are welded together under compression. They are sealed with O-type film or toothed seals. The tooth surface of the toothed seal matches the processed pot surface. Insulation is carried out with insulating pads or organic compound pads (2) Low-voltage integral insulating joints, joints with pressures greater than L.0MPa usually have two types. One type is composed of two short tubes. The inner surface of the expanded part of one tube section is processed into a tooth shape, and the outer surface of the other tube section is also processed into a tooth shape. A flexible plastic sleeve is bonded to the outer surface of the tooth shape and installed to the expanded part of the other tube section, and then pressed downward to form an integral insulating joint. Another type (see Figure 4.2.1-3) is similar in structure to the high-voltage type, but is simpler, with only a few sensitive components. The final assembly is usually done by cold forging or extrusion to lock under external force instead of welding. (3) Clamp-type insulating joint (see Figure 42.1-4). The clamp-type joint includes a carrier ring, and the back of a beautiful ring is conical. The two sections of the ring surface are sealed with an O-ring and insulated by an insulating gasket. Two semi-annular clamps are used to connect them together with bolts through the convex flange of the card box: the flange is usually locked with a welding plate. The processing head is as follows: 4.2.1-4 Integral insulating joint (low voltage) 4.2.1.4 Insulation Green union (see Figure 4.21-5) Interchangeable unions are usually used for electrical insulation of urban heating and gas supply pipes. They are suitable for high and low pressures and consist of two flanges that are screwed to the ends of the pipes to be connected. The outer end of one of the flanges is threaded and connected by a nut, and the nut is insulated from the other flange end with a dielectric material: an O-ring or gasket is placed between the two mating surfaces. Figure 4.2.1-4 Typical Caviar type ground pressure head hidden explosion 42.1-5 Typical insulating union 4.2.1.5 Insulation short pipe. When the insulation device is installed in a pipeline conveying brine or other electrolytic liquid, the resistance of the electrolyte solution circuit must be as large as possible to minimize the internal current. The current density leaving the pipe wall and entering the electrolyte solution is directly related to the corrosion rate inside the pipeline at that location. This current density is also directly related to the conductivity of the electrolyte solution and the potential across the insulation component, and is inversely proportional to the length of the internal insulation coating. High resistance can be provided by inserting a section of high-quality non-conductive or non-metallic pipe section into the pipeline. When a non-conductive lined pipe section is used, one end of the pipe fitting should use any of the devices described in 4.2.1.1 to 4.2.1.4 of this standard. Figure 4.2.16 shows the location of the lining: When non-metallic pipe fittings are used, the insulating devices described in 4.2.11 to 4.2.1.4 of this standard are not required. For a given electrolytic history, the length of the insulating short pipe section is determined by the allowable internal corrosion and the expected voltage across the pipe section. For example, for some users, regardless of the pipe diameter, a 6m long short pipe section is recommended: for pipelines with a fluid current of approximately 302·cm and a maximum voltage difference of 1.5V.
, the insulation knee push (such as body type)
on the electric surface
a Yong certificate society
inland fast quantity society photo
comfort pipe fittings
Figure 42.1-6 Typical insulating short pipe
4.2.1.6 Pure insulated pipe joints (see Figure 4.2.1-) There are three basic types of insulating pipe joints available for application, which are generally more suitable for low-pressure channels. (1) Insulating pipe joints fixed with screws, which consist of a cylindrical steel ring, two elastic washers and an additional circular ring, connected into a body by a set of long bolts. Insulation can be provided by a plastic insulating pad and a plastic insulating sleeve under a steel additional ring. (2) Boltless insulating pipe joints with mechanical sealing system, which consist of a short section of slow steel or cast iron, two elastic washers, two passports (supports) and two end nuts. It consists of a complete cotton rubber sleeve, plastic and end washers to provide insulation
(3) Boltless insulating pipe joint with hydraulic sealing system, which consists of a steel sleeve with a required gasket, sealed by internal (or external) water pressure acting on the outer shell, and insulation is provided by plastic or insulating washers and plastic pipe washers at one end of the pipe. 4.2.1.7 Mechanically opened and tapped insulating sleeve (see Figure 42.1-8) It consists of a sleeve assembled on the pipe: the two halves of the sleeve are connected by bolts and washers. Under the pressure of the pipeline, a section inside the sleeve is cut off using a sleeve milling cutter and a reading assembly, and insulating plastic is provided at one end of the sleeve to achieve insulation. Ahg
Di Jian brand
Figure 4.21-7 Typical night war pipe technology head
In screw mechanical tight type 6) No screw design type: C pressure reduction tight type protection A
Additional photos
Figure 4.21-Typical mechanical opening type insulation tank 4.3 Electrical insulation tank between pipelines and other structures
4.3.1 Appropriate electrical insulation of pipes passing through metal sleeves or casings: Steel sleeves or sleeves are usually used when conveying pipes through roads, railways, rivers, etc. At this time, the conveying pipe, sleeve or casing should be electrically insulated from each other. In order to achieve the purpose of electrical insulation, insulating positioning pads are pre-installed around the conveying pipe. These insulating spacers are set at regular intervals along the delivery pipe before the pipe is inserted into the casing or sleeve (see Figure 4.3.1). As long as the auxiliary delivery pipe and the casing are actually separated, the electrical insulation provided by the insulating spacers for the casing and the delivery pipe is reliable, because the insulating spacers can neither ensure that the delivery pipe is centered in the casing nor prevent its movement. Movement of the delivery pipe caused by soil settlement or operating conditions may cause one or both ends of the casing to come into direct contact with the delivery pipe. To prevent the slow entry of foreign matter, appropriate nozzle seals should be used. 12
Pipeline oil flow
4.3.2 Pipeline bridge insulation
Ao type measurement
Reat awakening welcome you
Figure 4.3.1 Casing insulation positioning pad
4.3.2.1 In order to make the cathodic protection transmission pipe and metal pipe bridge, steel bridge and trestle electrically insulated, the pipeline support on the pipe bridge should be equipped with pads to make the pipeline and the variable support bracket electrically insulated. Appropriate materials can be selected from nylon, oxyprene or glass ceramic. The selected material seat is suitable for the operation of the pipeline, environmental conditions and electrical performance requirements of the village material.
4.3.2.2 An electrical insulation device can be used to insulate the overhead pipe section from the underground pipeline protected by the open pole. In this case, a jumper conductor can be connected to the pipeline. Its specifications should be able to transmit the cathodic protection current: to maintain electrical continuity along the cable section (Figure 4.3.2)1 In order to make the cathodic protection transmission pipeline electrically insulated from metal pipe bridges, steel bridges and trestles, the pipeline support on the pipe bridge should be equipped with pads to make the pipeline electrically insulated from the variable support bracket. Appropriate materials can be selected from nylon, oxyprene or glass ceramics. The selected material seat should be suitable for the operation of the pipeline, environmental conditions and electrical performance requirements of the village material.
4.3.2.2 Electrical insulation devices can be used to insulate the overhead pipeline section from the underground pipeline protected by the cathode. In this case, a jumper conductor can be connected to the pipeline. Its specifications should be able to transmit the cathodic protection current: to maintain electrical continuity along the electrically insulated cable section (Figure 4.3.2)1 In order to make the cathodic protection transmission pipeline electrically insulated from metal pipe bridges, steel bridges and trestles, the pipeline support on the pipe bridge should be equipped with pads to make the pipeline electrically insulated from the variable support bracket. Appropriate materials can be selected from nylon, oxyprene or glass ceramics. The selected material seat should be suitable for the operation of the pipeline, environmental conditions and electrical performance requirements of the village material.
4.3.2.2 Electrical insulation devices can be used to insulate the overhead pipeline section from the underground pipeline protected by the cathode. In this case, a jumper conductor can be connected to the pipeline. Its specifications should be able to transmit the cathodic protection current: to maintain electrical continuity along the electrically insulated cable section (Figure 4.3.2)
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.