標準編號:	SH/T 3097-2017
中文名稱:	石油化工靜電接地設計規范
英文名稱:	Specification for design of static electricity earthing in petrochemical industry
行業分類:	SH    石油化工行業標準
發布機構:	中華人民共和國工業和信息化部
發布日期:	2017-07-07
實施日期:	2018-1-1
標準狀態:	valid
替代舊標準:	SH 3097-2000 石油化工靜電接地設計規范
翻譯語言:	英文
文件格式:	PDF
中文字符數:	30000 字
翻譯價格(元):	2900.0
交付時間:	付款后 1 個工作日

Codeofchina.com is in charge of this English translation. In case of any doubt about the English translation, the Chinese original shall be considered authoritative. This Specification was revised by the drafting group according to the requirements of Notice on issuing the plan for the development and revision of the fourth batch of professional standards in 2012 (GONGXINTINGKE [2012] No.252) issued by the Ministry of Industry and Information Technology, through extensive investigation, careful summarization of practical experience, reference to relevant international and foreign advanced standards and extensive solicitation of opinions. This Specification contains five clauses and three annexes, with the main contents as follows: electrostatic earthing area, electrostatic earthing method and requirements of earthing resistance of electrostatic earthing system; general requirements for electrostatic earthing terminal, earthing plate, earthing branch line, earthing main line, earthing electrode and specific connection; general requirements for petrochemical enterprise with area of electrostatic hazards. The following technical deviations have been made with respect to the former edition: ——The nouns and terms are verified and some nouns and terms not used in this Specification are deleted; ——The electrostatic earthing area is specified in detail; ——The setting requirements of special metal earthing plate are modified; ——The requirements for electrostatic earthing connection are modified; ——The clauses for selection of electrostatic earthing materials are added; ——The parameters of volume resistivity are modified; ——The specific requirements for electrostatic earthing of storage tank and piping system are modified; ——Requirements are made more detailed for some clauses. Annexes of this Specification are informative. This standard was issued in 2000 for the first time and revised in 2016 for the first time. This is the first revision. Specification for design of electrostatic earthing in petrochemical industry 1 Scope This Specification specifies the electrostatic earthing area and method as well as requirements for design of electrostatic earthing system of petrochemical enterprises. This Specification is applicable to the design of electrostatic earthing for constructed, extended and renovated engineering of petrochemical enterprises. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. GB/T 50065-2011 Code for design of ac electrical installations earthing GB 50813-2012 Code for design static explosion prevention in petrochemical powders silo GB 50169-2006 Code for construction and acceptance of grounding connection electric equipment installation engineering GB 50174-2008 Code for design of electronic information system room GB 50611-2010 Code for design of protection of electrostatic discharge in electronic engineering GB 12158-2006 General guideline for preventing electrostatic accidents GB 13348-2009 Safety rules of static electricity with relation to liquid petroleum products 3 Terms and definitions For the purposes of this specification, the following terms and definitions apply. 3.1 static electricity excess or insufficient electrical charge on the surface of an object, which is relatively static for observer, by which the magnetic field effect caused may be neglected compared with the electric field effect, and which may be produced by physical processes such as contact and separation of substances, electrostatic induction, polarization of medium and attachment of charged particles and is produced and accumulated on materials, devices, human bodies, equipment and structures during production, storage and transport 3.2 electrostatic field electric field formed by static electricity around it 3.3 electrified body object or system with unequal amounts of positive and negative charges and showing electrical characteristics to the outside world 3.4 electrified area part of an electrified body where static electricity accumulates 3.5 electrostatic characteristic parameters of substance a) volume resistivity physical quantity characterizing electrical conductivity in objects, which is the resistance value of material per unit cross-sectional area and unit length, expressed in Ω·m b) surface resistivity physical quantity characterizing the conductivity of the surface of an object, which is the resistance value between two opposite sides of a square material, and has nothing to do with the thickness of the object and the size of the square, expressed in Ω c) conductivity physical quantity characterizing the conductivity of materials, whose product with the electric field intensity is equal to the conduction current density, that is, σE = j, expressed in S/m ? 3.6 electro static electrification, accumulation and dissipation a) electro static electrification process of charging that appears macroscopically due to contact and separation of substances, electrostatic induction, polarization of medium and attachment of charged particles which causes unbalance of positive and negative charges or uneven charge distribution b) electro static accumulation process of electrostatic charge accumulation in which the rate of electro static electrification on an object exceeds that of electro static dissipation due to some electrification factors c) electro static leakage process in which the charges on an electrified body are conducted to the earth through the electrified body itself or other objects, so that the charges disappear partially or completely d) electro static dissipation (decay) process in which the charges on an electrified body partially or completely disappear due to electrostatic neutralization, electrostatic leakage and electrostatic discharge e) stray current any current that does not flow according to specified paths, such as the earth, pipeline in contact with the earth and other metal objects or structures 3.7 electrostatic discharge phenomenon that the dielectric is broken down and discharge is conducted after the energy of electrostatic field reaches a certain level caused by transfer of electrostatic charges between objects with different electrostatic potentials due to direct contact or electrostatic field induction ? 3.8 material a) electrostatic conductor material with low resistivity, on which it is difficult to accumulate electrostatic charges if it is not insulated from earth and whose volume resistivity is less than or equal to 1×106Ω·m b) electrostatic sub-conductor solid surface with volume resistivity greater than 1×106Ω·m and surface resistivity ranging from 1×107Ω to 1×1010 Ω c) electrostatic non-conductor material with very high resistivity, on which a sufficient amount of electrostatic charge may be accumulated to cause various electrostatic phenomena d) electrostatic conductive material material with high electrical conductivity, such as metal and carbon, and materials that make objects have electrostatic conductivity by other methods, such as doping conductive materials into insulating materials e) anti-static fabric fabric with the function of preventing electro static accumulation which is produced through a certain process to make the surface resistivity of fibre be reduced 3.9 electrostatic safety and disaster prevention a) electrostatic safety situations and conditions under which people injury, equipment damage or property loss due to electrostatic phenomenon do not occur in the production process and environments (systems) ? b) electrostatic accident phenomenon or event that causes the production system, equipment, technological process, materials and products to fail or damage (such as productivity slowdown, poor product quality, and even failure and destruction) due to the action of some electrostatic phenomenon c) electrostatic disaster phenomenon or accident such as property loss, personal casualty caused by electrostatic discharge, such as fire, explosion, electrostatic shock and secondary accident caused thereby d) electrostatic shock pathophysiological effects when the human body is passed through by the instantaneous impulse current generated by the electrostatic discharge generated from electrified body to human body, from electrified body with static electricity to earthing conductor or between human bodies e) secondary accident personnel injuries caused by falling from high altitude or touching other obstacles due to the imbalance of human body caused by electrostatic shock; or phenomenon or event that causes the consequences of existing fires and explosions to be worse f) area of electrostatic hazards general designation of working areas whose space exists explosive mixture that may be detonated by static electricity, or where such explosive mixture is directly processed, treated and operated 3.10 electrostatic earthing a) electrostatic earthing earthing set to prevent the dangerous effects of static electricity on people and equipment b) electrostatic earthing system external lead-out channel through which the charge on the electrified body leaks and dissipates to the earth c) direct electrostatic earthing earthing method for earthing objects through metal conductors d) indirect electrostatic earthing earthing method for earthing objects through non-metallic conductive materials or anti-static materials and anti-static products e) connection measures to electrically connect objects without good conductive paths to each other so that they are at the same potential f) classification on resistance of electrostatic earthing 1) leakage resistance of static electricity total resistance of the measured point of the object to the earth when the object is not charged 2) earthing resistance of static electricity resistance of electrostatic earthing system to earth, in which, the resistance between equipment shell and earth is called earthing resistance of static electricity, and that between earthing electrode and earth is called earthing electrode-to-earth resistance 4 Basic requirements 4.1 Electrostatic earthing area 4.1.1 Electrostatic earthing measures shall be taken when equipment, piping, operating tool and human body might produce and accumulate static electricity and thereby cause electrostatic hazards in production, processing, storage and transport: a) Equipment, gas holder and storage tank for producing, processing and storing inflammable and explosive gases and liquids; b) Piping and various valves for conveying flammable and explosive liquids and gases; c) Tank trucks (tankers), oil tanks, loading stages and rails, crane pipes, equipment and pipelines for loading and unloading flammable and explosive liquids and gases; d) Equipment and pipelines for producing and transporting combustible dust. 4.1.2 The following parts shall be earthed for the purpose of electrostatic earthing: a) Conductors that are installed inside the equipment and cannot normally be inspected from the outside; b) Metal parts mounted on insulated objects; c) Conductors used in conjunction with insulated objects; d) Conductors insulated by coatings or powders; e) Conductors which are prone to corrosion and consequent poor contact; f) Conductors suspended on the liquid surface. 4.1.3 The earth terminals of various static electricity eliminator shall be earthed as required. 4.1.4 Special electrostatic earthing measures may not be taken in the following cases (except for computers, electronic instruments, etc.): a) The metal conductors have been electrically connected to the earthing systems for lightning protection, electric protection, stray current protection, electromagnetic shielding, etc.; b) The metal conductors, such as buried metal structures, metal pipework, and reinforcements of structures are in a tight mechanical connection, and there is sufficient electrostatic conductivity between the metal contact surfaces in any case. 4.1.5 Metal pipe sections that have been cathodically protected shall not be electrostatically earthed. 4.1.6 In addition to this Specification, the design of electrostatic earthing shall also meet the requirements of the current relevant mandatory standards of the nation. 4.2 Electrostatic earthing method 4.2.1 Direct electrostatic earthing: The electrostatic conductor shall be earthed directly with a metal conductor.

Foreword i 1 Scope 2 Normative references 3 Terms and definitions 4 Basic requirements 4.1 Electrostatic earthing area 4.2 Electrostatic earthing method 4.3 Earthing resistance of electrostatic earthing system 4.4 Electrostatic earthing terminal and earthing plate 4.5 Electrostatic earthing branch line and connecting line 4.6 Electrostatic earthing main line and earthing electrode 4.7 Selection of electrostatic earthing materials for electrostatic earthing main lines and earthing electrode 4.8 Electrostatic earthing connection 5 Technical requirements 5.1 Fixed equipment 5.2 Storage tank 5.3 Piping system 5.4 Railway platform and tank truck 5.5 Bus station and tank truck 5.6 Pier 5.7 Powder processing, storage and transportation equipment 5.8 Spouting devices of gas and vapour 5.9 Chemical fibre equipment 5.10 Measures for discharging static electricity of human body 5.11 Electrostatic earthing of computer room and electronic instrument room Annex A (Informative) Test method of electrostatic earthing Annex B (Informative) Precautions in electrostatic earthing Annex C (Informative) Typical figures for electrostatic earthing connections Bibliography Explanation of wording in this Specification

石油化工靜電接地設計規范 1 范圍 本規范規定了石油化工企業靜電接地的范圍、方式及靜電接地系統設計的要求。 本規范適用于石油化工企業的新建、擴建和改建工程的靜電接地設計。 2 規范性引用文件 下列文件對于本規范的應用是必不可少的。凡是注日期的引用文件，僅注日期的版本適用于本規范。凡是不注日期的引用文件，其最新版本(包括所有的修改單)適用于本規范。 GB/T 50065—2011 交流電氣裝置的接地設計規范 GB 50813—2012 石油化工粉體料倉防靜電燃爆設計規范 GB 50169—2006 電氣裝置安裝工程接地裝置施工及驗收規范 GB 50174—2008 電子信息系統機房設計規范 GB 50611—2010 電子工程防靜電設計規范 GB 12158—2006 防止靜電事故通用導則 GB 13348—2009 液體石油產品靜電安全規程 3 術語和定義 下列術語和定義適用于本規范。 3.1 靜電 static electricity 靜電是對觀測者相對靜止的、處于物體表面過剩或不足的電荷。由它所引起的磁場效應較之電場效應可以忽略不計。靜電可由物質的接觸與分離、靜電感應、介質極化和帶電微粒的附著等物理過程而產生，是生產儲運過程中在物料、裝置、人體、器材和構筑物上產生和積累起來的靜電。 3.2 靜電場 electrostatic field 靜電在其周圍形成的電場。 3.3 帶電體 electrified body 正負電荷數量不相等，對外界顯示電的特性的物體或系統。 3.4 帶電區 electrified area 帶電體上積聚靜電的部位。 3.5 物質靜電特征參數 a) 體積電阻率 volume resistivity 表征物體內導電性能的物理量。它是單位橫截面積、單位長度上材料的電阻值，其單位為歐·米(Ω·m)。 b) 表面電阻率 surface resistivity 表征物體表面導電性能的物理量。它是正方形材料兩對邊間的電阻值，與物體厚度及正方形大小無關，其單位為歐(Ω)。 c) 電導率 conductivity 表征材料導電性能的物理量。其與電場強度之乘積等于傳導電流密度，即σE=j。電導率的單位為西門子/米(S/m)。 3.6 靜電起電、積聚和消散 a) 靜電起電 electro static electrification 由于物體的接觸分離、靜電感應、介質極化和帶電微粒的附著等原因，使物體正負電荷失去平衡或電荷分布不均，而在宏觀上呈現帶電的過程。 b) 靜電積聚 electro static accumulation 由于某種起電因素使物體上靜電起電的速率超過靜電消散的速率而在其上呈現靜電荷的積累過程。 c) 靜電泄漏 electro static leakage 帶電體上的電荷通過帶電體自身或其他物體等途徑向大地傳導而使之部分或全部消失的過程。 d) 靜電消散 electro static dissipation (decay) 帶電體上的電荷由于靜電中和、靜電泄漏、靜電放電而使之部分或全部消失的過程。 e) 雜散電流 stray current 任何不按指定的通路而流動的電流，這些非指定的通路可以是大地、與大地接觸的管線和其他金屬物體或構筑物。 3.7 靜電放電 electrostatic discharge 具有不同靜電電位的物體，由于直接接觸或靜電場感應引起物體間靜電電荷的轉移；靜電電場的能量達到一定程度后，擊穿其間介質而進行放電的現象就是靜電放電。 3.8 材料 a) 靜電導體 electrostatic conductor 一種具有較低的電阻率，若不與地絕緣則其上難于積聚靜電荷的材料。體積電阻率小于或等于1×106Ω·m。 b) 靜電亞導體 electrostatic sub-conductor 體積電阻率大于1×106Ω·m，表面電阻率為1×107Ω～1×1010Ω的固體表面。 c) 靜電非導體 electrostatic non-conductor 一種具有很高的電阻率，因此能在其上積聚足夠數量的靜電荷從而引起各種靜電現象的材料。 d) 導靜電材料 electrostatic conductive material 指金屬和碳等電導率大的材料，以及用其他方法(如在絕緣材料中摻入導電材料等)使物體具有導靜電性能的材料。 e) 防靜電織物 anti-static fabric 通過某種工藝方法，使纖維表面電阻率降低，從而形成或生產出的一種具有防止靜電積聚的織物。 3.9 靜電安全及災害預防 a) 靜電安全 electrostatic safety 指在生產過程及各種環境(系統)中，不發生由于靜電現象而導致人的傷害、設備損壞或財產損失的狀況和條件。 b) 靜電故障 electrostatic accident 由于某種靜電現象的作用，導致生產系統、設備、工藝過程、材料、產品等發生故障、損害(如生產率下降、產品質量不良，以至失效、破壞等)的現象或事件。 c) 靜電災害 electrostatic disaster 由于靜電放電而導致發生財產損失或人員傷亡的危害、損害的現象或意外事件(如火災、爆炸、靜電電擊以及由此而造成的二次事故等)。 d) 靜電電擊 electrostatic shock 由于帶電體向人體，或帶靜電的人體向接地的導體，以及人體相互間發生靜電放電，其所產生的瞬間沖擊電流通過人體而引起的病理生理效應。 e) 二次事故 secondary accident 由于靜電電擊使人體失去平衡，導致人員由高空墜落或觸及其他障礙物而引起的傷害；或造成已存在的火災、爆炸的后果進一步擴大等危害的現象或事件。 f) 靜電危險場所 area of electrostatic hazards 空間存在可由靜電引爆的爆炸性混合物，或對其進行直接加工、處理和操作等工藝作業場所的統稱。 3.10 靜電接地 a) 靜電接地 electrostatic earthing 為防止靜電對人身和設備等的危險作用而設的接地。 b) 靜電接地系統 electrostatic eatrhing system 帶電體上的電荷向大地泄漏、消散的外界導出通道。 c) 直接靜電接地 direct electrostatic earthing 通過金屬導體使物體接地的一種接地方式。 d) 間接靜電接地 indirect electrostatic eatrhing 通過非金屬導電材料或防靜電材料以及防靜電制品使物體接地的一種接地方式。 e) 連接 connection 將彼此沒有良好導電通路的物體進行導電性連接，使相互間大體上處于相同電位的措施。 f) 靜電接地的電阻分類 1) 靜電泄漏電阻 leakage resistance of static electricity 物體在不帶電的情況下，物體的被測點對大地的總電阻。 2) 靜電接地電阻 earthing resistance of static electricity 靜電接地系統的對地電阻。設備外殼至大地的電阻稱為靜電接地電阻，接地體至大地的電阻稱為接地體對地電阻。 4 基本規定 4.1 靜電接地的范圍 4.1.1 在生產加工、儲運過程中，設備、管道、操作工具及人體等，有可能產生和積聚靜電而造成靜電危害時，應采取靜電接地措施： a) 生產、加工、儲存易燃易爆氣體和液體的設備及氣柜、儲罐等； b) 輸送易燃易爆液體和氣體的管道及各種閥門； c) 裝卸易燃易爆液體和氣體的罐(槽)車，油罐，裝卸棧橋、鐵軌，鶴管，以及設備、管線等； d) 生產、輸送可燃粉塵的設備和管線。 4.1.2 在進行靜電接地時，應包括下列部位的接地： a) 裝在設備內部而通常從外部不能進行檢查的導體； b) 安裝在絕緣物體上的金屬部件； c) 與絕緣物體同時使用的導體； d) 被涂料或粉體絕緣的導體； e) 容易腐蝕而造成接觸不良的導體； f) 在液面上懸浮的導體。 4.1.3 各種靜電消除器的接地端，應按要求進行接地。 4.1.4 在下列情況下，可不采取專用的靜電接地措施(計算機、電子儀器等除外)： a) 當金屬導體已與防雷、電氣保護、防雜散電流、電磁屏蔽等的接地系統有電氣連接時； b) 當埋入地下的金屬構造物、金屬配管、構筑物的鋼筋等金屬導體間有緊密的機械連接，并在任何情況下金屬接觸面間有足夠的靜電導通性時。 4.1.5 當金屬管段已作陰極保護時，不應靜電接地。 4.1.6 靜電接地設計，除應符合本規范外，尚應符合國家現行有關強制性標準規范的規定。4.2 靜電接地方式 4.2.1 直接靜電接地：靜電導體應采用金屬導體進行直接接地。 4.2.2 間接靜電接地：為使金屬以外的靜電導體、靜電亞導體進行靜電接地，將其表面的局部或全部與接地的金屬體緊密相接的一種接地方式。 4.2.3 靜電非導體除應間接靜電接地外，尚應配合其他的防靜電措施。 4.3 靜電接地系統的接地電阻 4.3.1 靜電接地系統靜電接地電阻值不應大于106Ω。專設的靜電接地體的對地電阻值不應大于100Ω，在山區等土壤電阻率較高的地區，其對地電阻值不應大于1000Ω。 4.3.2 當其他接地裝置兼作靜電接地時，其接地電阻值應根據該接地裝置的要求確定。 4.4 靜電接地端子和接地板 4.4.1 應在設備、管道的一定位置上，設置專用的接地連接端子，作為靜電接地的連接點。4.4.2 接地連接端子的設置應符合下列要求： a) 不易受到外力損傷； b) 便于檢查維修； c) 便于與接地線相連； d) 不妨礙操作； e) 盡量避開容易積聚可燃混合物以及容易銹蝕的地點。 4.4.3 靜電接地端子有下列幾種： a) 設備、管道外殼(包括設備支座、耳座)上預留出的裸露金屬表面； b) 設備、管道的金屬螺栓連接部位； c) 接地端子排板； d) 專用的金屬接地板。 4.4.4 專用金屬接地板的設置應符合下列要求： a) 金屬接地板可焊(或緊固)于設備、管道的金屬外殼或支座上。 b) 金屬接地板的材質，應與設備、管道的金屬外殼材質相近。 c) 用于管道靜電接地引下線的金屬接地板的截面不宜小于50mm×10mm，管道跨接用的金屬接地板的截面不宜小于50mm×6mm；最小有效長度宜為60mm。如管道有保溫層，該板應伸出保溫層外60mm。 d) 設備接地用的金屬接地板的截面不宜小于50mm×10mm，最小有效長度對小型設備宜為60mm，大型設備宜為110mm。如設備有保溫層，該板應伸出保溫層外60mm或110mm。 e) 接地用螺栓規格不應小于M10。 f) 當選用鋼筋混凝土基礎作靜電接地體時，應選擇適當部位預埋200mm×200mm×6mm鋼板，鋼板上再焊專用的金屬接地板。預埋鋼板的錨筋應與基礎主鋼筋相焊接。 4.5 靜電接地支線和連接線 4.5.1 靜電接地支線和連接線，應采用具有足夠機械強度、耐腐蝕和不易斷線的多股金屬線或金屬體，規格可按表4.5.1確定。 表4.5.1 靜電接地支線、連接線的最小規格 設備類型 接地支線 連接線 固定設備 16mm2多股銅芯電線 φ8mm鍍鋅圓鋼 12mm×4mm鍍鋅扁鋼 6mm2銅芯軟絞線或軟銅編織線 大型移動設備 16mm2銅芯軟絞線或橡套銅芯軟電纜 — 一般移動設備 10mm2銅芯軟絞線或橡套銅芯軟電纜 — 振動和頻繁移動的器件 6mm2銅芯軟絞線 — 4.5.2 在振動和頻繁移動的器件上使用的接地導體不應采用單股線及金屬鏈。 4.6 靜電接地干線和接地體 4.6.1 靜電接地干線和接地體應與其他用途的接地裝置綜合考慮，統一布置。可利用保護接地干線、防雷電感應接地干線作為靜電接地干線使用，否則應專門設置靜電接地干線和接地體。 4.6.2 靜電接地干線的布置，應符合下列要求： a) 有利于設備、管道及需要在現場作靜電接地的移動物體的接地； b) 靜電接地干線在裝置內宜閉合環形布置，不同標高層或兩個閉合環之間的接地干線應至少有兩處連接。 4.6.3 下列接地干線或線路不得用于靜電接地： a) 三相四線制系統中的中性線； b) 整流所各級電壓的交流、直流保護接地系統； c) 直流回路的專用接地干線。 4.6.4 靜電接地體的設計應符合下列要求： a) 當靜電接地干線與保護接地干線在建構筑物內有兩點相連時，可不另設靜電接地體； b) 應充分利用自然接地體以及其他用途的接地體； c) 腐蝕環境中，宜根據腐蝕介質及腐蝕環境類別選用復合型耐腐蝕材料。 4.7 靜電接地干線和接地體靜電接地材質的選擇 4.7.1 靜電接地材質可選用鍍鋅鋼材、復合型防腐接地材料等。 4.7.2 當選用鍍鋅鋼材時，鋼材規格可按表4.7.1確定。 表4.7.1 靜電接地干線和接地體用鋼材的最小規格 名稱 單位 規格 地上 地下 扁鋼 截面積 厚度 100mm2 4mm 160mm2 4mm 圓鋼 直徑 φ12mm φ14mm 角鋼 規格 — 50mm×5mm 鋼管 直徑 — 50mm 4.7.3 當選用復合型防腐接地材料時，靜電接地干線和接地體用復合型防腐接地材料的最小規格可按照表4.7.2確定。 表4.7.2 靜電接地干線和接地體用復合型防腐接地材料的最小規格 名稱 單位 規則 地上 地下 復合型防腐扁鋼 截面積 厚度 100mm2 4mm 100mm2 4mm 復合型防腐圓鋼 直徑 φ12mm φ12mm 復合型防腐角鋼 規格 50mm×5mm 50mm×5mm 4.7.4 條文所規定的材質選擇是針對石油化工裝置的一般要求，對于特殊物料裝置，應根據其工藝產品特性確定接地材質的選型。 4.8 靜電接地的連接 4.8.1 接地端子與接地支線連接，應采用下列方式： a) 固定設備宜采用螺栓連接； b) 有振動、位移的物體，應采用撓性線連接； c) 移動式設備及工具，應采用電瓶夾頭、鱷式夾鉗，專用連接夾頭或磁力連接器等； d) 不應采用接地線與被接地體相纏繞的方法。 4.8.2 靜電接地體的連接應符合下列要求： a) 當采用搭接焊連接時，其搭接長度應是扁鋼寬度的2倍或圓鋼直徑的6倍，焊接處應進行防腐處理。 b) 當采用螺栓連接時，其金屬接觸面應去銹、除油污，并加防松螺帽或防松墊片； c) 當采用電池夾頭、鱷式夾鉗等器具連接時，有關連接部位應去銹、除油污。