低溫拉斷裝置（拉斷閥）解決方案

Cryogenic Breakaway Device(Breakaway Coupling)The solution

　　一.概述General Description

　　低溫裝卸液系統主要由液源站、槽車或者船舶的軟管、加液臂、閥門、管路系統連接，接口采用 DN25-DN100接口，或于加液槍或于干式接頭或于法蘭連接。加液管路上要求配備拉斷裝置(拉斷閥)，當連接件尚未脫離，而另一端的車或船或外界移動式設備離開，強大的外力將導致軟管或設備的損壞、低溫液體的泄漏危機安全事故時，低溫拉斷裝置在緊急狀況下及時保護設備和人員的安全而緊急關閉。

　　下面重點介紹該低溫拉斷裝置的結構原理及應用。

　　The cryogenic liquid loading and unloading system is mainly connected with the hose of the liquid source station, trailer or ship, refueling arm, valve and pipeline system, and its connector adopts DN25-DN100, connecting to fueling nozzle or dry joint or flange type. A breakaway device (breakaway coupling) is required on the refueling pipeline. When the connector is not separated but the other end of the vehicle or boat or external mobile device separated, strong external force will cause the damage to the hose or equipment. When the leakage of cryogenic liquid occurs, the cryogenic breakaway coupling can protect the safety of equipment and personnel in time and turn off emergently.

　　The structure principle and application of the cryogenic breakaway device are introduced as below

　　二.性能參數Performance parameters

　　1.公稱通徑Nominal Diameter：DN25---DN100

　　2.公稱壓力Nominal Pressure：PN16、PN25、PN40

　　3.設計溫度Design Temperature：-196℃

　　工作溫度：-196℃～+75℃(高溫上限 300℃)

　　Operating temperature: -196℃ ~ +75℃ (Max. Temperature 300℃)

　　脫離后密封率：根據不同介質設置 95%—100%密封率(管道泄壓)

　　Sealing rate after separation: 95%-100% sealing rate is set according to different media (pipeline pressure relief)

　　適用范圍：液氧、液氮、液氬、液化天然氣、乙烯、液氯、等低溫、常溫介質的氣體與液體

　　Application Media: Liquid Oxygen, Liquid Nitrogen, Liquid Argon, Liquefied Natural Gas, Ethylene, Liquid Chlorine, and other low temperature, room temperature media of gas and liquid

　　4.材質：殼體采用耐低溫的 304或 316L不銹鋼材料

　　Material: the shell is made of 304 or 316L stainless steel

　　裝配前進行深冷處理;密封材料采用耐超低溫特氟龍材料，密封面經特殊工藝加工達到密封要求。Cryogenic treatment before assembly; The sealing material is made of cryogenic Teflon material, and the sealing surface is processed by special technology to meet the sealing requirements.

　　5.殼體密封性：零泄漏;Shell sealing: no leakage;

　　6.使用性能：Operational performance

　　1)緊急情況下能夠使裝卸設備快速脫離;

　　2)常規操作時不會出現“拉斷”;

　　3)拉斷后分開的兩部分能有效達到設計密封。

　　1) In case of emergency, the loading and unloading equipment can be quickly separated;

　　2) There will be no "break away" happened during routine operation;

　　3) The two parts separated can effectively achieve the design sealing.

　　7.流量：管線安裝拉斷閥后不影響裝卸車原有的流量，流通率設計達到球閥流通率級別;不限流、不截流。

　　Flow rate: the pipeline with breakaway valve does not affect the original flow rate of loading and unloading, flow rate designed reaches the ball valve's flow rate level; Unlimited flow, no interception.

　　三.結構原理Structure principle

　　圖 1所示為緊急拉斷裝置的結構圖，主要由兩個閥體組成，單邊閥體的主體均采用彈簧力關閉的結構，其關閉力來自于閥瓣彈簧本身。

　　PICTURE 1 shows the structure of the emergency breakaway device, which is mainly composed of two valve bodies. The main body of the unilateral valve body adopts spring force closing structure, its closing force comes from the disc spring itself.

　　圖 1緊急拉斷裝置PICTURE 1 Emergency breakaway device

　　1.主體結構The main structure

　　左閥體Left body

　　右閥體Right body

　　限位桿Limit lever

　　閥瓣Disc

　　主密封Main sealing

　　閥蓋密封Valve bonnet seal

　　拉斷螺栓Breakaway bolt

　　2.拉斷裝置由兩部分閥體組成，中間為拉斷螺栓，兩邊由獨立的單個閥體組成，

　　主要由殼體、閥瓣、主密封圈、導向板、拉斷螺栓、卡簧組成。

　　The breakaway device consists of two parts of the valve bodys, the middle is the breakaway bolt, and the two sides are composed of an independent single valve body.It is mainly composed of shell, valve disc, main sealing ring, guide plate, breakaway bolt and circlip.

　　1)殼體拉斷螺栓連接左右閥體對接;中間為流通孔，流通面積的設計達到流通

　　率的要求;導流板作為彈簧和閥芯的支座;拉斷裝置連接形式采用法蘭或焊接方式連接。

　　Breakaway bolt of shell connects left and right valve bodys, and the middle is the circulation hole, circulation area designed meets the requirements of circulation rate. The guide plate is used as the support of the spring and the valve trim. The connection form of breakaway device adopts flanged or welding type.

　　2)閥瓣閥瓣為頂針結構，設計限位裝置，有利于保證良好的密封性，操作簡單，易于維護維修，同時避免閥芯錯位不通液現象。

　　Valve disc is thimble structure with limit device which is designed to ensure good sealing, simple operation, easy maintenance, and avoid the spool dislocation to cause no liquid phenomenon.

　　3)密封左右閥體中間采用耐低溫 DURABLA密封材料，凹凸面水線設計，主次二級密封，此密封材料能有良好的高低溫延伸性，不脆裂，低溫效果好，能保證長期重復使用。

　　DURABLA sealing material is used between the left and right valve body, with concave-convex surface waterline design and primary /secondary sealings. This sealing material has good elongation at high and low temperature, not brittle, no crack,and have long lifetime.

　　4)閥體在外力拉斷后的密封度為可設置性，根據不同的介質設計不同的密封率，一般LNG、LN2、LAr建議設置密封率為97%，(使用方也可以自行考慮密封率的問題拆裝閥芯密封墊即可達到全密封與泄壓要求)。由于低溫液體介質在常溫大氣中容易急劇膨脹，導致軟管內壓力急劇升高，閥體設計為不全密封，允許部分泄壓從而保護軟管不會壓力過高而爆裂;液氧類易燃易爆設置密封率100%，DN65以上大口徑閥體另外設置了放散孔。

　　The sealing degree of valve body after being breakaway by external force can be set. Different sealing rates are designed according to different media. Normally, The sealing rate of LNG, LN2 and LAr is recommended to be 97%. (Users can also consider the sealing rate.Full sealing and pressure relief requirements can be achieved by removing and installing the valve core gasket.) Because the low temperature liquid media in the room temperature atmosphere is easy to be expanded rapidly and urgently, resulting in a sharp pressure increase in hose, but the valve body is designed to not fully sealed, allowing partial pressure relief to protect the hose from bursting because of too high pressure. The sealing degree of flammable explosive media like Liquid oxygen must set as 100%. The venting hole has been set on the valve body for the size >=DN65.

　　3.拉斷機構：拉斷機構既要保證“緊急拉斷”時使設備能夠自動、快速拉斷;又要保證拉斷前有“緩沖期”，避免常規操作時出現“拉斷”，影響正常裝卸作業;裝卸鶴管類拉動力根據用戶的要求設置相應的拉斷裝置。

　　Breakaway Actuator: Breakaway actuator should ensure that the equipment can be automatically and quickly broken away when emergency pulling happened. Also, the actuator must ensure that there is a buffering period before separated, and avoid the occurrence of breakaway during routine operation which may affect normal loading and unloading operations. Corresponding breakway device can be customized according to required pulling force of loading and unloading refueling arm.

　　1)軟管型拉斷機構：主要由雙頭拉斷螺栓或單頭拉斷螺栓、螺母組成。由于金屬軟管都具有較好的柔性，當槽車超位時逐漸出現張緊并在一定范圍內延伸的過程，這個過程提示操作人員“若不采取措施停車，將會出現緊急拉斷”，軟管的優點就在于自身存在緩沖過程。

　　Hose-type breakaway actuator

　　It is mainly composed of double head breaking bolt or single head breaking bolt and nut.

　　Because metal hose has good flexibility, when the trailer is over the position, it gradually tenses and extends within a certain range. This process reminds of the operator that if you do not take measures to stop, there will be an emergency pull break. The advantage of the hose lies in its own buffering process.

　　四.工作過程Working process

　　如圖 2所示為緊急拉斷裝置安裝在軟管工藝管線上的示意圖，該套裝卸設備主要由軟管(金屬軟管)、快速接頭、緊急拉斷裝置和專用截止閥等組成。

　　PICTURE 2 shows a schematic diagram of emergency breakaway device installed on the hose processing pipeline. This set of loading and unloading equipment is mainly composed of hose (metal hose), connector, emergency breakaway device and globe valve etc..

　　1.槽車接口Trailer interface

　　6.截斷閥門Block valves

　　2.3卸車管線Unloading line

　　7.8液相管Liquid pipe

　　4.9.緊急拉斷裝置Emergency breakaway device

　　9.支架(可選)Bracket (optional)

　　5.法蘭接口Flange interface

　　圖 2現場布局示意圖PICTURE 2 Schematic diagram of site layout

　　1. 拉斷過程

　　正常裝卸時，軟管處于松弛自由狀態;當槽車或船舶馳離，其接口未與站場設備分離時,軟管張緊并逐漸延伸拉長，超出極限范圍，拉斷螺栓斷裂，兩端閥體分離。分離后，一半閥體留在管線上，另一半閥體留在軟管上，在內部彈簧力的作用下實現密封。

　　1. Breakaway Process

　　During normal loading and unloading process, the flexible hose is in a relaxed and free state. When the trailer or ship is driven away and its interface is not separated from the station equipment, the flexible hose tenses and gradually extends and elongates beyond the limit range, the breakaway bolt breaks, and the valve bodies at both ends are separated. After separation, half valve body is left in the line and the other half in the hose, which is sealed by internal spring force.

　　注意：緊急拉斷后，必須迅速關閉站線閥門，卸掉管線壓力;在管線排空前不得用外力擠壓閥瓣，否則會造成介質批量泄漏，引發安全事故。

　　Note: after emergency breakaway, the valves on station line must be closed quickly to discharge the pipeline pressure. Do not use external force to squeeze the valve disc before pipeline discharged to empty, otherwise it will cause mass leakage of media and serious accident.

　　2.拉斷后的復原排空管線后進行恢復工作。

　　緊急拉斷裝置恢復前檢查左右閥體中間密封是否損壞,有損壞則卸下主密封座更換閥體主密封或者閥瓣密封墊;否則只需更換新的拉斷螺栓便可?；謴筒僮鲿r，用通用螺栓鎖緊兩端閥體，靜置5-10分鐘，然后依次換上拉斷螺栓并擰緊螺母，鎖緊拉斷螺栓的扭力值為4-5Nm，完成恢復工作。

　　Recovery after breakaway

　　Check whether the middle seal between the left and right valve body is damaged before the emergency breakaway device is restored. If there is damage, remove the main seal seat and replace the main seal of the valve body or the valve disc sealing. Otherwise, replace the breakaway bolt. During the recovery operation, lock the valve bodies at both ends with universal bolts, let them standing for 5-10 minutes, and then replace thebreakaway bolts and tighten the nuts with the torque of 4-5Nm and then complete the recovery work.

　　3.初次進液注意事項及故障排除

　　初次進液時，務必預冷，待閥體輕微結霜狀態是先觀察閥體中間連接位置是否有輕微泄露，若有泄露，關閉進液閥門，排出壓力，用二把10mm扳手逐步鎖緊每個拉斷螺栓，切勿用無法掌握力度的大型活動扳手去鎖緊，容易導致螺栓斷裂。

　　Notes and troubleshooting for initial liquid injection

　　Be sure do the precooling, when the body is slightly frosted, observe if there is a slight leakage among body connection. If there is any leakage, shut down the liquid inlet valve and discharge the pressure. Use 2 pcs of10 mm wrenches gradually lock each snap bolt, do not use large adjustable wrench with no grip to tighten, it will cause the bolt fracture.

　　4.安裝方向

　　拉斷閥安裝無方向，箭頭示意的方向兩端皆可連接不同方向。

　　Installation direction

　　There is no direction to install the breakaway coupling. Both ends of the arrow direction can be connected in different directions