往复泵外文翻译


    Chemical and Petroleum Engineering Vol 40 Nos 11–12 2004
    COMPRESSORS PUMPS
    REFRIGERATION ENGINEERING
    UPDATING PISTON PUMPS FOR OIL
    PRODUCTION

    B S Zakharov1 G N Sharikov2
    and E G Kormishin2

    The threeplunger acid treatment pump SIN32 and the twocylinder doubleacting pump NPTs32 with four working chambers (for cementing units) have been updated to control pump delivery The fluid delivery diagrams for pumps of various designs are examined and the test results are reported

    In drilling and oil production singleacting threeplunger (triplex) pumps or doubleacting twocylinder (duplex) pumps are used
    In injecting reagents (clay drilling mud water cement acid etc) into wells depending on the technology appliedit is required to inject the fluid in amounts ranging from the maximum to the minimum in a single operation If the bed accepts the injected fluid well it becomes necessary to maximize pump delivery for quick completion of the operation If on the other hand the bed does not accept the fluid well it becomes necessary to reduce pump delivery so as to restrict the injection pressure to the safe limit At present because of wear of well (downhole) equipment the permissible injection
    pressure is not higher than 10–15 MPa
    The delivery of a piston (reciprocating) or a plunger (displacement) type of pump can be controlled in the following ways
    • by installing several pumps with identical or different pumping capacities
    • by changing the drive rotation speed
    • by using cylinders (plungers) of the required size
    • by channeling a part of the fluid into a bypass and
    • by dismounting one or several valves
    The first version is used essentially in drilling In oil production generally all versions are used either individually or in some combination
    All pumping units designed for injection of various fluids (fluidal materials) for cementing hydraulic formation fracturing hydraulic sandjet flushing of sand bridges and other flushing operations in oil and gas wells are mounted on the chassis of motor vehicles (trucks) tractors caterpillar (tracked) carriers and specially made carriages
    The operating parameters of the pumps (delivery and injection pressure) depend on the power of the drive and maximum and minimum speed of the engine and the pump The pump delivery can be changed by changing the number of pump strokes without stopping the engine with the help of a gearbox (by gear shifting) and with stopping of the engine by installing cylinders of the required size Replacement of the cylinders takes a lot of time and is not always possible in a continuous echnological process In the existing pumping plants the delivery variation range is inadequate At the minimum rotation speed and cylinder diameter the delivery remains extremely high and for injecting the fluid into the bed the pressure has to be raised above what is permissible

    Assigned by NGDU Zainskneft’ Ékogermet carried out updating of two types of pumps namely SIN32 and NPTs32
    In the threeplunger (triplex) acid treatment pump SIN32 for reducing the minimum delivery down to 10 m3hplungers having a diameter of 125 mm were replaced with plungers having a diameter of 55 mm As a result the theoretical pump delivery was reduced from 16 down to 33 m3h Further reduction of the pump delivery was achieved by reducing the rotation speed of the vehicle engine to the possible minimum (500–600 rpm)
    Simultaneously with this a new design of packing glands (sealing devices) of plungers of the UPN55 type was developedIt was based on Zakharov mechanical seal [1] which demonstrated high reliability and durability in suckerrod (oil) pumps The sealing units and the pistons with a diameter of 55 mm were made for the SIN32 pump by ÉLKAMneftemash in Perm Its finishing and testing were done by Ékogermet jointly with NGDU Zainskneft’
    The design of the UPN55type plunger seal is shown in Fig 1 The combined seal consists of the main threestage mechanical seal 4 and an elastic sealing collar 2 Each stage of the mechanical seal consists of ten rings that are elastically pressed against each other and simultaneously against the plunger surface The rings are pressed against the
    plunger in pairs from the opposite sides The next pair is turned relative to the preceding one by 90º The rings are pressed in the axial direction by rubber rings of round cross section and in the radial direction by rubber girdles with eccentric collars The plunger 5 is made of steel 45 and is chromiumplated and the sealing rings are of bronze Three
    cartridges with mechanical seals were installed in the housing bore 3 with a clearance that helps selfcentering of the seals relative to the plunger The cartridges are pressed together by a round nut 1 through a bushing with the sealing collar 2 There are holes in the housing for injecting oil and draining out the overflow into the receiving (suction) line of the pump
    In contrast to the wellknown elastic glands the mechanical seal does not require periodic adjustments and ensures reliable operation of the assembly over a long period [2] Use of the updated SIN32 pump having a UPN55 type of mechanical plunger seals confirmed that the proposed design operationally fit
    From August through December 2003 NGDU Zainskneft’ carried out seven bottomhole treatments (BHT) of six wells using the updated SIN32 pump Different types of technological operations were carried out in the wells mud acid BHT muriatic (hydrochloric) acid BHT injection of the reagents SNPKh9021 MIAPROM and RMD for which SIN32 and ATs32 pumping units were generally used If acid or any other reagent could not be forced through (injected) at 12–15 MPa pressure a lowcapacity unit was connected with the SIN32 pump In that case the injection pressure dropped by 2–4 MPaInjection was completed at the thirdgear speed of the engine

    The NGDU technologists believe that connecting a lowdelivery unit with an SIN32 pump offers the following advantages
    • possibility for continuous injection of acids and reagents in case of low intake capacity of the bed and for prevention of opening up of the fractures (hydraulic fracturing) of the collector and excessive rise in flow string testing pressure
    • extended operating life of the flow string by virtue of pressure stabilization during injection and
    • action of the acid throughout the perforation period and more complete reaction with the rock when the acid infiltrates the bed
    Since the maximally possible delivery of the SIN32 pump is reduced at least fivefold NGDU Zainskneft’ proposed to perform all BHTs by injecting acids into the bed with the aid of a lowcapacity unit and all other operations with a standard unit In that case however it would be necessary to place in the well instead of one two units which have to be handledby two teams ie it will entail additional manpower and costs Moreover a lowcapacity unit is not always fully utilized(does not operate to full capacity) and often stalls
    Thus for a specific size of the cylinder it is necessary to reduce the pump delivery down to the minimum and consequentlyto broaden the range of control of the pump capacity toward its reduction while maintaining maximally possible delivery
    In multichamber pumps this issue is resolved by shutting down (disengaging) one or several working chambers
    In duplex plunger pumps disengaging one or two chambers will cause significantly uneven delivery hydraulic shocks disruption of the balance of loads on the drive and failure of the pump
    In doubleacting twocylinder (duplex) pumps having four working chambers of the NPTs32(9T) type which are installed for example in ATs32 cementing units the delivery can be reduced by disengaging two rod chambers which is achieved by removing two delivery (pressure) valves (Fig 2)
    The delivery of the NPTs32 type of pump (duplex) having four chambers is
    Q 2(2F – ƒ)Sn
    where F is the crosssectional area of the cylinder with a diameter Dc dm2 ƒ is the crosssectional area of the rod with a diameter dr dm2 S is the stroke length dm and n is the number of double strokes per minute
    If the delivery (pressure) valves are removed from the rod chambers the fourchamber pump turns into a twochamber one with differentially acting cylinders The delivery of such a pump Q1 2FSn

    If the valves from the front chambers are removed the pump delivery can be determined by the equation Q2 2(F – ƒ)Sn
    Reduction of delivery by disengaging the rear (rod) chambers depends on the factor k1 (2 – ƒF) and by disengaging the front chambers on the factor k2 [2 + ƒ (F – ƒ)] It can be readily seen that for reducing delivery the front chambers have to be disengaged However theory and practice show that disengagement of the rod chambers is more advisable
    Thus in NPTs32 type of pump having cylinders of 90 100 115 and 127 mm diameter and rods of 45 mm diameter the delivery can be reduced 175–187 times by removing the valves from the rod chambers At low loads (pressure drop
    not more than 15 MPa and minimal delivery) the engine of the motor vehicle KrAZ250 can run steadily at a rotation speed of 550 rpm In the second gear with minimum engine rotation speed the delivery of a pump with a cylinder of 90 mm diameter can be reduced down to 10 m3h
    Unlike the SIN32 pump the delivery of the NPTs32 pump can be controlled during the technological operation and reducing or raising the delivery can change the pump output Removal and installation of two valves do not take too long
    Let us see how the uniformity of pump delivery will change upon removal of the valves
    It is well known that the instantaneous output of a singlecylinder singleacting pump is
    q Frsiná 05FSsiná
    where r is the radius of the crank and á is the crankshaftturning angle
    The ratio of the maximum instantaneous delivery to the average delivery of the pump is called coefficient of delivery nonuniformity ä QmaxQav
    The average delivery of a fourchamber pump in one turn of the crank Qav 2(2F – ƒ)S2·314
    The maximum instantaneous delivery of a pump having four chambers and cranks turning at a 90° angle (Fig 3a)Qmax FSsin45° 07FS For the NPTs32 type of duplex pump (Dc 90–127 mm and dr 45 mm) ä 125–117
    After this as the delivery (pressure) valves are removed from the rod chambers the average delivery of a twochamber differential (differentiallyacting) pump (Fig 3b) Qav 2FS2·314 FS 314
    For such pumps the maximum instantaneous delivery
    Qmax (F – ƒ)Ssin45° 07(F – ƒ)S ä 165–191
    For all other types of delivery variation on account of removal of valves (in succession all front pressure valves or crosswise one of the front chambers and another of the rod chambers in another cylinder) the coefficient ä will be much higher In general in differential pumps to reduce the nonuniformity in the pump delivery the rod diameter is so chosen that its crosssectional area is half that of the cylinder ie ƒ 05F In that case the delivery nonuniformity coefficient will be the lowest for twocylinder differential pumps ä 07·05FS·314 FS 1099
    For each cylinder in order to get the coefficient ä 1099 it will be necessary to make a rod of a fixed diameter (6370 80 and 90 mm respectively) But then if the pump operates with all the valves there will be a substantial increase in delivery nonuniformity and decrease in pump delivery If the NPTs32 pump is required to operate in two modes it is perhaps advisable to make a rod of 55 mm diameter (for cylinders of 90 and 100 mm diameter) and of 70 mm diameter (for cylinders of 115 and 127 mm diameter) In that case the delivery nonuniformity coefficient will be identical for both modes of pump operation ä 135–138 The theoretical pump delivery on account of increase in the diameter of the rod in a duplextype pump will decrease roughly by 10
    Let us see how the delivery nonuniformity will change if the pressure (delivery) valves are removed from the front chambers (Fig 3c) The delivery as was noticed earlier will decrease more than twofold
    The average delivery of a seriesproduced NPTs32 pump operating with two rodchambers is
    Qav 2(F – ƒ)S2·314 (075–087)FS 314
    The maximum instantaneous pump delivery (forward stroke) is
    Qmax FSsin45° 07FS
    The minimum instantaneous delivery (back stroke) is
    Qmin FSsin45° 07FS 07(025–0125)FS
    The delivery nonuniformity coefficient is
    ä (Qmax + Qmin)Qav 387–345
    If the rod diameter of such a differential pump is increased the delivery nonuniformity will increase further andtherefore it will be necessary to remove valves only from the rod chambers
    In seriesproduced NPTs32 type of pumps having four working chambers the nonuniformity of the fluid flow in the delivery (pressure) and suction (intake) lines will be identical and will depend on the rod diameter The smaller the crosssectional area of the rod the greater will the fluid flow uniformity be
    In the suction (intake) line of a differential pump the flow nonuniformity increases considerably because only two chambers operate and the cranks of the crankshaft are turned by not 180° as is usual for singleacting twocylinder (duplex) pumps but by 90°
    The delivery nonuniformity coefficient in this case will be ä QmaxQav 2199
    Suction conditions of differential pumps just as of all other types of piston pumps can be improved by installing air suction surge chambers in the suction line and placing the fluid tanks above the pumping unit
    An NPTs32 type of differential pump was tested in field conditions in two modes with two front working chambers (the delivery valves were removed from the rod chambers) and with two rear rod chambers (the delivery valves were removed from the front chambers) During the tests the delivery Q and the pressure p were measured at various rates Cylinders with a diameter of 115 mm and rods with a diameter of 45 mm were installed in the pump The test results are reported in Tables 1 and 2 respectively





    The tests of the differential pump were performed in two wells In one well (Table 1) the residual pressure was 10 MPa and in the other (Table 2) 5 MPa
    It is evident from Table 1 that the measured deliveries are in accord with the calculated with due regard for the volumetric efficiency The average volumetric efficiency of the pump operating at the secondgear speed is 077 and at the thirdgear
    speed 065 With increase of the rotation speed the volumetric efficiency decreases and pressure fluctuations rise from 5 to 30 In spite of high delivery nonuniformity coefficient (ä 186) the pump functioned satisfactorily
    It follows from Table 2 that the measured deliveries are not always in accord with the calculated This is so because of wide pressure fluctuations (from 70 to 550 ) in the delivery (pressure) line Accurate measurement of the rotation speed of an engine at such pressure fluctuations is practically impossible
    Thus it is proved both theoretically and by measurements that a duplex type of pump can be converted to a differential one only by removing the delivery (pressure) valves from the rod chamber In this regard in order to reduce the delivery nonuniformity of an NPTs32 type of pump it is necessary that the rod diameter be 55 or 70 mm depending on the diameter of the cylinder
    Based on the studies made and the operational data obtained the following steps may be recommended for improving the seriesproduced NPTs32 pump
    • to make pump with rod of two diameters namely 55 and 70 mm
    • to design valve system with option for disengaging it automatically or manually without disassembling the pump [3] and
    • to design piston and rod systems having mechanical seals
    REFERENCES
    1 B S Zakharov Piston and Plunger Pumps for Oil Production [in Russian] OAO VNIIOÉNG Moscow (2002)
    p 52
    2 N G Ibragimov G N Sharikov E G Kormishin and B S Zakharov Application for Invention No 2003125236
    Mechanical Seal of Plunger Pump [in Russian] 2003
    3 N G Ibragimov G N Sharikov E G Kormishin V S Isakov and B S Zakharov Application for Useable Model
    No 2004119790 TwoCylinder Piston Pump [in Russian]


    译文
    化工石油工程 卷40第11刊 C122004
    压缩机泵制冷工程
    新式活塞泵专油产品
    B S ZakharovG N SharikovEG Kormishin2

    SIN32酸处理泵三缸柱塞泵两缸双作泵工作NPTs32四室(影响固井优质率单位)已更新便控制泵流量种流体输送泵设计图进行检查测试结果报告
    钻井石油生产中单作三柱塞(三缸)泵双作两缸(双面)泵
    注射试剂(粘土钻井泥浆水水泥酸等)油井里身技术应型£¬需注入流体总量高低限度次操作步骤里面假机架注入流畅流体必限度泵排量操作快速完成果方面机架未接受良流体必减少泵排量限制注射压力控制安全范围目前井(井)设备磨损允许注射
    压力高1015兆帕
    活塞(复式)柱塞(位移)类型泵控制方面:
    •通安装组具相力泵获泵输送力
    •通改变驱动旋转转速
    •通改变泵求求气缸(活塞)尺寸
    •通引导部分流体旁路
    •拆装阀
    第版钻井石油生产中般单独某组合版
    抽油机设计种液体注射fluidal)影响固井优质率材料 抽油机组注入种流体(流体材料)泥浆水力压裂液压砂喷射洗石油天然气井作业安装汽车(卡车)机箱拖拉机卡特彼勒(踪)载流子特制车厢
    泵(流量注射压力)操作参数取决驱动器发动机泵高高动力该泵流量改变通齿轮变速器(通齿轮位移)停止发动机情况改变泵程发动机停止时通安装需气缸尺寸调节排量柱塞更换需花费时间柱塞更换具连续性现泵机装置流量变化范围够规范低转速气缸直径排量非常高注入底座流体压力高允许范围

    图1UPN55type密封相结合SIN32柱塞泵

    NGDU Zainskneft kogermet进行两种类型泵更新SIN32NPTs32
    三柱塞(三缸)酸处理泵SIN32排量减少低10流量立方米时柱塞直径125毫米换活塞直径55毫米泵理输送率16降33立方米时泵流量进步减少通减少发动机转速低速度(500 600分钟转速)
    时着点种关填函料(密封装置)新设计发展正扎哈罗夫机械密封[1]基础展示高性耐久性抽油杆(油)泵密封装置55毫米直径活塞 SIN32泵| LKAMneftemash做终完成测试测试kogermetNGDU Zainskneft完成
    该UPN55型柱塞密封设计图1示联合阀座threestage机械密封4弹性密封轴环2组成机械密封阶段包括十弹性环时柱塞表面施加压力密封环挤压
    柱塞两侧面接相原转90度环压圆截面橡胶圈轴径方通橡胶环束缚轴偏心柱塞545号钢镀铬密封环镀铜组成三组
    机械密封盒安装箱体钻孔部位3利泵动定心方案压起圆螺母1通套密封圈2结合 孔外壳注入石油终止啦泵输出端溢流
    相较著名弹性汽封机械密封需定期调整确保程序长期运行[2]新SIN32机械柱塞泵证实拟议设计密封UPN55类型操作行
    八月2003年12月NGDU Zainskneft完成7井底六口井处理(BHT)新SIN32泵类型操作技术进行井:泥酸甲苯盐酸(盐酸)酸甲苯试剂SNPKh 9021注射MIAPROMRMDSIN32ATS 32抽油机普遍果酸试剂法通(注入)1215 MPa压力低容量装置SIN32泵相连接种情况注射压力降24兆帕¡ 注射操作发动机第三档速度完成

    图2液压原理图部分a)两缸泵四工作腔(双)
    b)differentiallyacting圆柱体1)前面(头)工作室(横截面积F)2)方(杆)室(横截面积
    Fƒ)3)压力(交货)阀4)吸(摄入)阀门(5)杆截面ƒ)

    The NGDU技术专家认连接带低配送单位SIN32泵提供列优点:
    •连续注入性酸试剂试剂果较低注射入机构防治破损(水力压裂)
    情况度涨压力测试出流量压力
    •稳定压力延长注射液柱寿命
    •整行动期间穿孔摇晃时酸试剂更完整浸润机构
    SIN32泵减少五倍流量NGD​​U Zainskneft提出种通注射执行BHTs酸助lowcapacity单元操作标准件种情况然必放置代两单元必须处理两队说需额外力成 外低容量单位总充分利(运作满负荷)起作
    特定气缸必减少泵输出低限度拓展减少泵流量力控制范围时保持限度泵流量
    室泵问题停止(分离)工作线程
    双缸柱塞泵脱离两分庭造成明显均匀排量 液压击扰乱驱动器负载衡导致泵障
    双动两缸(双面)四工作腔32(9齿)类型已安装方说ATS32固井单位排量通减少分离两柱塞杆降低两阀流量(压力)(图2)
    NPTs32 型泵流量(双面)四腔室

    中FDM2汽缸横截面面积f活塞杆横截面面积S行程长度n分钟双笔画数
    果流量(压力)阀活塞杆移四腔泵变成两间隔气缸种输出泵Q1 2FSn

    图3 图中液体交付活塞泵1)duplextypebc)differentialtype(前面
    杆工作腔分运作)

    果正面阀门移泵输送第二方程式

    减少泵排量取决系数k1 (2 – ƒF)k2 [2 + ƒ (F – ƒ)]容易出减少排量分离开然理实践表明活塞杆脱离更明智
    泵NPTs32 型气缸具90100115127毫米45毫米直径杆减少泵排量通移活塞杆气阀175187杆长低负载(压力降超15 MPa流量)发动机KrAZ 250稳固运行550 rpm发动机转速发动机转速低第二齿轮泵90毫米直径圆筒传递会降10立方米时
    SIN32泵NPTs32泵输送程中控制技术操作降低提高流量改变泵输出拆安装两阀门太长
    改变泵输送均匀性阀门切情况
    众周知单缸单动泵瞬时输出

    中r曲柄半径曲轴转角瞬间传递泵均流量率称流量均匀系数:

    四腔泵体均流量转曲轴Qav 2(2F – ƒ)S2·314
    四腔室泵瞬时流量曲柄旋转90正负角(图3a)Qmax FSsin45° 07FS转NPTs32型双缸泵(直流 90 ° C127毫米博士 45毫米)
    流量(压力)阀杆移差异双缸(差异效)泵(图3b)Qav 2FS2·314 FS 314
    样泵瞬时流量

    全部类型流量变化移阀(接着前压力阀横正面腔室杆腔室气缸)系数较类型高般说泵减少泵输出均匀性杆直径精心设计横截面面积气缸半f 05F种情况输出均匀系数两缸泵低差:

    气缸系数?? 1099必做固定直径(分63708090毫米)杆果泵阀门运行会幅增加流量均匀性泵输出降果 NPTs32型泵需两种模式运行取直径55毫米(90缸100毫米直径)活塞杆直径70毫米(115汽缸直径127毫米)种情况泵输出均匀系数两种运行模式完全相:

    关理增加泵杆直径双缸型泵流量减少10%
    导致泵流量均匀性改变果压力(流量)阀(图3C)腔室移流量正先前发现减少超两倍
    系列生产 NPTs32泵工作两杆腔室均流量
    Qav 2(F – ƒ)S2·314 (075–087)FS 314
    瞬时泵输送(前程)
    Qmax FSsin45° 07FS
    低瞬时流量(逆行程)
    Qmin FSsin45° 07FS 07(025–0125)FS
    流量均匀系数

    果种差异泵杆直径增加流量均匀性会进步增加必消泵腔室气阀
    系列生产NPTs32型泵四工作腔室流量(压力)吸入(摄入)流量均匀性相取决杆直径较杆截面积越流体流动均匀性越高
    吸(进气)差分泵流量均匀性增加两腔室运作曲轴曲柄正负180正负旋转现象常见单作两缸(双面)泵
    流量均匀系数种情况

    泵吸条件差活塞泵类型通安装吸气调节室吸风调压室泵装置流体油槽加改善
    NPTs32型差动泵现场条件进行两种模式测试:两正面工作腔室(流量阀门拆杆腔)两轮杆工作腔室(流量阀门正面杆腔拆) 测试程中流量QP测量压力率汽缸直径115毫米杆直径45毫安装泵测试结果报告表12独立

    泵测试执行两实验中(表1)剩余压力10 MPa(表2)5兆帕
    表1见符合流量测量容积效率适考虑计算均第二齿轮泵运行速度容积效率077第三档
    速度快065着转速增加容积效率降低压力波动升530%泵高输出均匀系数 186)泵运作情况令满意
    测量流量符合计算结果表2压力波动(70550%)超出额定输出(压力)线精确测量种压力发动机转速波动测量
    理证明泵双缸类型转换通移流量(压力)阀门杆腔测量微弱差方面啦降低NPTs32型泵流量均匀性必杆直径5570毫米取决气缸直径
    研究基础提出获运行数面步骤推荐改善该系列生产NPTs32泵:
    •两泵杆直径改55mm70mm
    •设计阀门装置动脱离者手动拆离出泵[3]
    •设计机械密封活塞活塞杆系统
    参考文献
    1[俄罗斯]采油学士扎哈罗夫活塞活塞泵OAOVNIIO莫斯科(2002年)p°52
    2议员易卜拉欣莫夫沙瑞克夫KormishinBS扎哈罗夫发明号二十〇亿零三百十二万五千二百三十六应机械密封柱塞泵[俄罗斯]2003
    3议员易卜拉欣莫夫沙瑞克夫Kormishin伊萨科夫BS扎哈罗夫模型中应没G2两缸活塞泵[俄罗斯]
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