1、為了縮短船舶建造周期及保證船舶下水的大節點，軸系、舵系中心線確定在舵機艙平臺以下所有焊接、火工矯正、密性等全部結束并報檢通過后即可進行照光。In order to reduce the building time and ensure the node of ship launching , the jobs under steering gear cabin deck such as blocks erection、erections welding、distortion correction by flame、tightness and so on should be finished c

2、ompletely ,after finishing these jobs ,we will decide the centerline of shaft line & rudder line.1. 工具的選用 Tools and instrument激光經緯儀、光靶。Laser theodolite and optical target.2. 軸系中心線的確定Decide the centerline of the shaft-line.軸系中心線的確定應根據季節溫度變化來進行，夏天一般在晚上8-9點進行,冬天一般在下午5點左右進行, 或在陰天進行，在軸系中心線的確定過程中，船上不應

3、有能夠導致船體變形的工作在進行。This step should be done according to temperature change of the season of a year , in the estival season , this work should be done at evening 8-9 clock, and in the winterly season, this work should be done at afternoon 5 clock ,or in the cloudy day, and any work that can bring hull

4、deformation should be stopped. 1） 船體尾部理論軸中心面的確定。Decide the center plan of shaft line outer of E/R. 以中心線在船臺上的延伸點為基準，調整激光經緯儀“1”的軸線直至與船中心線重合。Adjust No.1 laser theodolite centerline overlap with hull C.L. basing on hull C.L. 將激光經緯儀“1”射出的光點延伸到船臺尾部光靶“3”上，根據機艙區域艙底龍骨平整度數據平均值為基線高度并在垂直方向向上平移軸系高度+船體板厚，則此點為軸系軸線

5、上一點。以此點作為參考點并打好樣沖點，同時將激光經緯儀旋轉180°將光點投射到尾柱上，并打好樣沖，這樣就可初步確定軸系尾部理論面。Extend the laser from No.1 theodolite to No.3 target, then according to the mean valve of flexibility of the keel under the ring of groove for main engine as datum high move No.1 theodolite up and down in vertical plan and measure

6、 the height of shaft line and thickness of armor plate, the point as a datum point in the shaft line, a laser point can be found in stern boss by turning No.1 theodolite 180°, and another mark will be made as the point. In this way, we can decide shaft center plan outer of E/R firstly.2） 機艙內軸系中

7、心線的確定 Decide the shaft line in E/R. 在機艙與尾管平面適當位置設立一激光經緯儀“2”，將光點延伸到船體外部的光靶“3”，使之與光靶“3”上的樣沖點重合。Put No.2 theodolite to fit at Fr15. Its laser beam to be extended to No.3 target and to be kept superposition with that mark made on No.3 target. 調整激光經緯儀“2”的位置，使之既能與船體尾柱上的樣沖點的連線相交，同時也能投影到光靶“3”上的樣沖點上，調整經緯儀高度與

8、光靶“3”上的樣沖點重合，然后將經緯儀“2”的位置固定。Move No.2 theodolite, and keep its height same as the mark on No.3 target and make the beam pass through the center of marks on stern boss, then fix No.2 theodolite.3） 軸系中心線的延伸 Extending the centerline of the shafting. 將激光經緯儀“2”調轉180°，將光點延伸并投影在機艙Fr40艙壁上，并確定光點位置，打好樣沖點

9、，這點與光靶“3”上的樣沖點的連線即為初步確定的理論軸線。Turn No.2 theodolite 1800, the laser beam can be extended to Fr40 bulkhead, make the mark again. Now we can say that the line decided by this point mark and that one on No.3 target is shaft line. 檢查主機底座中線與理論軸線的偏離距離，偏移范圍在±（5-10）mm之內。Check the deflection distance betw

10、een base line and shaft line. Allow deviation range to be within ±（5-10）mm. 3. 尾軸管鏜孔時軸線的確定Deciding centerline of stern boss1) 加工圓確定前的條件 Preparation for this step 本船上所有設備都已安裝到位或用重量相當放置在相的物品應位置上代替。All other equipments should be located or instead by others as same as the weight. 在本工藝進行的過程中，船上應停止沖

11、擊和有振動性的工作。When this step being done, any impacting work or vibration job should be stopped.2) 定軸系中心線Decide the centerline of shafting.如圖所示將激光經緯儀“2”放至機艙適當位置（如“圖-1”所示），調整高度和左右位置使射出的光點既能投影到光靶“3”上的基準點上，又能在旋轉1800后投影在Fr40艙壁的基準點上。則此時的經緯儀的軸線即為軸系的軸線。Set No.2 theodolite at suitability poison in engine room (s

12、ee fig. 1), and adjust by project the laser beam on No.3 target mark, then turn it 180°, project the laser beam on Fr40 bulkhead mark, in this way, the centerline of shafting can be decided.3) 在艉柱管前后端處各設一光靶（見“圖-4”，位置見“圖-1”），調整光靶中心使激光經緯儀射出的光束與光靶中靶中心點重合，即該光束即為尾柱管上的軸線。 Set an optical target on the

13、 both end of stern boss (see fig.1 & fig.4), adjust the center of optical target to make the center coincide with the beam projected by theodolite. This beam is the center of stern boss casting.4) 以光靶上的中心點為圓心作圓654、656、658、662、740及800，如圖2，所示800為檢驗圓。畫出加工圓并打好樣沖點。 Make circles654, 656, 658, 662, 740

14、 and inspection mark 800 basing on the center of the target as shown on fig.2.5) 同理以艉管前端處的光靶中心為圓心畫圓656、658、662、740和800，其中800作為檢驗圓（見“圖-3”）。打好樣沖點。others circles656, 658, 662, 740 and 800 (inspection mark) can be made on stern tube casting in the same way. (See fig.3)4. 舵系軸線的確定 Decide the centerline of

15、 ruder stoc1) 舵桿軸線的確定Decide the centerline of rudder stock. 在掛舵臂兩軸孔處各設立兩個光靶，如“圖-5”中所示。光靶尺寸按圖-4所示。Set two (2) targets on the rudder horn as shown on fig. 5. (Target dimension refer to fig.4) 采用重錘法使重錘與船臺上的Fr0肋位重合，調整光靶使細線處于光靶的中心。或者采用激光法，先放置一個激光經緯儀在船體中心平面內，用細鋼絲從舵機艙穿過舵承處光靶孔中心使其保持垂直，用激光經緯儀掃描該細線，使激光經緯儀射出的光

16、束跟細線重合，然后在垂直于Fr0肋位的任一位置重設一激光經緯儀，調整細線使之與該激光經緯儀射出的光束重合，那么該細線則為舵系的中心線 Use plumb coincide with the Fr0 location on the berth, then adjust the target and make the wire just pass through the center. Or use laser to decide the centerline of rudder line. Set a theodolite in the midship plane, use a steel wire through the hole center hole of targets in the horn casting, and keep the steel wire vertical, at the same time make the steel wire coinside with the theodolite projected laser beam . set an anther theodolite in plump midship and keep the steel wire coinside