【導(dǎo)讀】液壓缸、起重器和柱塞的基本術(shù)語可以被看作為同義詞。通常首先描述的是。缸，這些形式的液壓缸單一作用式并有其相對的應(yīng)用局限。件下可獲得的輸出力可以被彈簧抗力所減輕。擇器交替實(shí)現(xiàn)輸入口，輸出口作用。最大的可獲得的輸出的僅比單作用液壓缸所。通常液壓缸由循環(huán)管，活塞和桿運(yùn)動處兩側(cè)的密封組織，活塞桿可被設(shè)。近年來，隨著我國國民經(jīng)濟(jì)的持續(xù)快速發(fā)展，我國的石油消費(fèi)量逐年增加。相比之下，我國石油機(jī)械制造生產(chǎn)增長比較緩慢，供需矛盾日益突出。針對修井作業(yè)中人力上卸抽油桿螺紋效率低,勞動。主要技術(shù)參數(shù)和室內(nèi)試驗(yàn)情況，現(xiàn)場應(yīng)用結(jié)果表明,采用液壓抽油桿鉗?？纱蟠鬁p少抽油桿脫扣次數(shù),提高修井質(zhì)量和修井速度。受到的阻力及機(jī)械摩擦等也引起一定的能量損失，致使液壓傳動的效率較低。在低溫條件或高溫條件下采用液壓傳動有較大的困難。當(dāng)液壓系統(tǒng)產(chǎn)生故障時，故障原因不易查找，排除困難等通。箍，并按標(biāo)準(zhǔn)規(guī)定設(shè)計(jì)。量,確保完成整個工作過程。

　　

【正文】 ers to provide sure string grip with maximum gripping forces. The freefloating type of reaction system eliminates any shear and bending loads across the tool joint, thereby subjecting the joint only to torsion loads and minimizing the risk of damaging thread flanks or shoulders by galling. The separable freefloating backup is mechanically and hydraulically (via hoses) linked to the tong and is selfpensating for connection thread travel in both makeup and breakout directions. A load cell (torque cylinder) is fitted between tong and backup and, by selection, can be used to record makeup or breakout torques. Three jaws provide the gripping means. A gripping system in the same manner as in the tong (also with separate hydraulic circuit) ensures a centric clamping action of the hydraulic clamping cylinder. The backup clamping range is designed to acmodate all variations in collar diameters within their nominal size range from 9 in. through maximum 24in. diameter. TORQUE MEASUREMENT Bending and shearing forces are eliminated by the freefloating backup system as these forces are symmetrically distributed into the torque posts, allowing measurement of applied torque to be made very accurately. A torque measuring system bined with a power tong with free floating backup eliminates oscillations and additional interfering forces. Consequently, makeup and breakout torque can be measured with the same accuracy. Torque load is measured with an active pressiontype load cell. The force 15 is directly measured within the torque reaction system of the freefloating backup. If desired, a makeup or a breakout with the Riser Tong 21300 can be controlled using a torque/turn system that records the torque over turn graph while makingup (or breakingout) the connection. That halts the makeup process when the preselected optimum torque value is reached. Many of the production riser connectors used today are externally shouldered and require “preloading” of those shoulders to ensure they will withstand the bending stresses caused by the environment while not backing out. This is achieved by applying “delta torque” to the connections after the connection has shouldered. Manufacturers require that this delta torque is applied and controlled within very tight tolerances. New proprietary software was designed to analyze the connection torque/turn data in real time, then applying a predetermined amount of delta torque or delta turns to the connection for final makeup. TONG MANEUVERING The Riser Tong 21300 was designed with various types of rigs in mind. The tong can either be suspended from a lift cylinder and manipulated to and from well center with the Weatherford Power Scope, or the other option is to integrate the Riser Tong 21300 into the Weatherford railmounted Power Frame and Servo Frame system. Depending upon the application, all functions of the tong can be controlled either directly from the hydraulic control panel at the side of the tong or via a remote control panel. Remote control can be acplished through an airover hydraulic control or electronically with the tong being an integral part of an electronic control system. In this case, the tong and the tong carrier device can be connected to the rig’s zone management system to prevent collisions between different devices such as Power Frame, top drive, or pipe handling systems. CASE HISTORIES Two 21300 tongs were delivered for the West Seno Tension Leg Platform (TLP) operated by Unocal in the Makassar Strait in Indonesia. The challenge 16 presented to Weatherford was to run approximately 3,000 ft of 13 3/8in. steel casing (below mud line), titanium tapered stress joint (crossover joint), and approximately 3,000 ft of production risers (above mud line) as one string in a severely deviated open hole. The production risers consisted of joints with weld on connectors in the high stress areas that required more than 100,000 ft/lbs of makeup/breakout torque, and specialized threaded and coupled connectors for the remainder of the string above the mud line. Due to fatigue concerns, the requirements for handling the production risers were minimal marking to the OD of the risers. As a result, Micro Grip slips were developed for the project and used in a 500 ton spider with a remotely operated retractable base plate. The slips did not perate into the pipe body and the spider was remotely and safely retracted from well center to acmodate all large OD riser string ponents. Two tongs were rigged up simultaneously opposite each other on the rig floor to handle the nonmarking requirements of the threaded and coupled risers and the high torque requirements of the weldon riser connections. Due to open hole conditions, it was imperative to reduce time on slips for the pipe string to avoid stuck pipe. A semimechanized 2480 tong with a pneumatic/hydraulic gripping device and aluminum inserts was used to make up the threaded and coupled risers, leaving no peration into the pipe body wall. This tong was positioned on and off the pipe remotely with the hydraulic Push Master, and the tong doors were actuated remotely open/close. The semimechanized 21300 tong was used to make up all weldon specialty connections and was positioned on and off the pipe with the Power Scope. The tong doors were also actuated remotely open/close. All production risers and casing was installed with no human stabber in the derrick. The derrick mounted St