1、Lesson 25 Anchor windlass and Mooring winch 錨機(jī)和絞纜機(jī),Anchor handling equipment,The windlass（錨機(jī)） is the usual anchor handling device where one machine may be used to handle both anchor .,A more recent development , particularly on large vessels, is the split windlass where one machine is used for each

2、anchor.,One unit of a split windlass(分離式錨機(jī)） is shown in Fig.25-1.,The rotating units consist of a cable lifter(錨鏈輪） with shaped smug（凸起） to grip the anchor cable（錨鏈）,a mooring drum（絞纜筒） for paying out（放松） or letting go（放出） of mooring wires and a warp end for warping duties.,Each of these units maybe

3、 separately engaged（嚙合） or disengaged by means or a dog clutch（牙嵌離合器） ,although the warp end is often driven in association with the mooring drum.,A spur gear（正齒輪） assembly transmits the motor drive to shaft where the various dog clutches enable the power take-off .,Separate band brakes（獨(dú)立式剎車(chē)） are f

4、itted hold the cable lifter and the mooring drum（絞纜筒） when the power is switched off.,The cable lifter unit（錨鏈輪） , show in Fig.25-1, is mounted so as to raise and lower the cable from the spurling pipe（錨鏈管） ,which is at the top and center of the chain or cable locker（錨鏈艙） .,Details of the snugs（卡塊）

5、used to grip the cable and band brake（帶式剎車(chē)） can be seen.,Anchor capstans（起錨絞盤(pán)） are used in some installations where the cable lifter rotates about a vertical axis.,Only the cable lifter unit is located on deck ,the driving machinery（驅(qū)動(dòng)機(jī)械） being on the deck below .,A warping end or barrel may be driv

6、en by the same unit and is positioned near the cable lifter.,The efficient working of the anchor windlass is essential to the safety of the ship . An anchor windlass can expect to fulfill（滿足） the following:,1.The windlass cable lifter brakes must be able to control the running anchor and cable when

7、the cable lifter is disconnected from the gear during “l(fā)etting go”（放錨）.,Average cable speeds vary between 5-7 m/sec during this operation,2.The windlass must be able heave a certain weight of cable at a specified speed（額定轉(zhuǎn)速） .,This “full load” duty of the windlass varies but is commonly between 4 an

8、d 6 times the weight of one anchor ,the speed of haul being at least 9 m/min up to 15 m/min.,3.The braking effort（剎車(chē)效果） obtained at the cable lifter must be at least equal to 40 percent of the breaking strength of the cable .,Most anchor handing equipments incorporate（包含） warp ends for mooring purpo

9、ses（系泊） and line speeds of up to 0.75 to 1.00 m/sec are required .,The most conventional types of equipment in use are as follows.,Windlasses,This equipment is self-contained （獨(dú)立的）and normally one prime mover drives two cablelifters and two warp ends（絞纜端）,the latter may not be declutchable（離合裝置） and

10、 ,if so, rotate when the cablelifters are engaged.,There is some variation in detail design of cable lifters and in their drives.,Due to the low speed of rotation required of the cablelifter whilst heaving anchor,(345r/min) a high gear reduction (齒輪減速機(jī)構(gòu)） is needed when the windlass is driven by a hi

11、gh speed electric of hydraulic motor.,This is generally obtained by using a high ratio worm gear（渦輪） followed by a single step of spur gears（單級(jí)正齒輪） between the warpend shaft and cablelifters.,Alternatively, multi steps of spur gears are used.,Capstans（起錨機(jī)） with this type of equipment the driving mac

12、hinery is situated below deck and the cablelifters are mounted horizontally being driven by vertical shafts.,Mooring winches,Mooring winches provide the facility for tensioning the wire up to the stalling capacity（堵轉(zhuǎn)轉(zhuǎn)矩） of the winch（絞車(chē)）, usually 1.5 times full load（全負(fù)荷）,thereafter the load is held（握

13、持） by the prime mover brake or barrel brake when the power is shut off.,The winch cannot pay out wire unless the brake is overhauled（超越） or recover wire unless manually operated, thus wires may become slack.,The majority of automatic mooring winches（自動(dòng)系纜機(jī)） are spur geared（正齒輪） to improve the backwar

14、d efficiency of the gear train for rendering,the gearing（齒輪機(jī)構(gòu)） and bearings being totally enclosed and lubricated from the oil sump.,On larger mooring winches where a barrel brake is fitted, it is now common practice to design the brake to withstand the breaking strength of the mooring wire.,Worm ge

15、ared（渦輪蝸桿） automatic mooring winches are uncommon,as the multistart（多次起動(dòng)） feature required to improve gear efficiency reduces the main advantage of the worm gear i.e the high gear ratio（傳動(dòng)比較高）.,Winches with various arrangements of barrels are the usual mooring equipment used on board ships .,A moori

16、ng winch is Fig.25-2 where the various parts can be identified.,The winch barrel or drum is used for hauling（收緊） in or letting out the wires or ropes which will fasten the ship to the shore.,The warp end is used when moving the ship using ropes or wires fastened to bollards（系纜樁） ashore and wrap arou

17、nd the warpend of tile winch.,The construction of a mooring winch will now be examined, again with respect to Fig.25-2.,The motor drive is passed through a spur gear transmission（直齒輪傳動(dòng)機(jī)構(gòu)）, a clutch and thus to the drum（卷筒） and warp end.,A substantial（堅(jiān)實(shí)的） frame supports the assembly and a band brake is used to hold the drum when required.,The control arrangements for the drive motor permit forward or reverse rotation together with a selection of speeds during operation.,Modern mooring winches are arranged as automatic self tensioning units（自動(dòng)張緊裝置）.,The flow of the tides（潮） or chang