GUIDELINES ON SHAFTING ALIGNMENT phần 5

nhìn chi tiết về chuyển vị tương đối trên dưới bể đôi trong phần động cơ của dòng sự châm biến. Như có thể nhìn thấy từ hình. , có một khác biệt nhỏ giữa chuyển vị tương đối trong mẫu B và mẫu B + M / E. Sự khác biệt này là do phần chỗ ngồi động cơ của dòng sự châm biến và nó đã được Ngoài ra, như hình. 7,11 cũng cho thấy, độ lớn của sự lệch trong Model Cụ thể là, sự khác biệt trong hầu như không thấy trong các phần khác | ClassNK PART A GUIDELINES ON SHAFTING ALIGNMENT TAKING INTO ACCOUNT VARIATION IN BEARING OFFSETS WHILE IN SERVICE el B and and it was ction in Model difference in the Fig. A detailed view of relative displacements on doub portion of the shafting line. As can be seen from Fig. there is a slight differe Model B M E. This difference is attributable to t hardly seen in other portions. In addition as Fi B M E clearly decreased at the engine seating relative displacements is caused by increases in t engine. Although the change of the because engine alignments of re offsets. Therefore a reliable an and the ship. ntegration of the main hould never be disregarded even small changes in bearing structural model of the main engine 36 ClassNK PART A GUIDELINES ON SHAFTING ALIGNMENT TAKING INTO ACCOUNT VARIATION IN BEARING OFFSETS WHILE IN SERVICE 8. Prediction of Thermal Deformation of Engine Bedplate Temperature of Engine Structure in Running Condition In the running condition the upper structure of engine which is located close to the combustion chambers has in principal a higher temperature than lower structures such as the bedplate although the exact value depends on the size and output of the engine size. Figure shows the approximate temperatures of the cylinder block frame column and bedplate for a large-sized engine. CYLINDER BLOCK 80 90 c FRAME 40 50C BED PLATE 40 50C Fig. An example o structure in the running desp Thermal Deformation Although thermal deform however will affec translation and positions is hoggin str imensionally only vertical displacement acement can be decomposed into parallel later. The parallel rise in height of all bearing erature of the engine bedplate. On the other hand ongitudinal expansion of the upper parts of the engine igher temperature of these parts compared with the lower ing offsets which has less effect than hogging deformation on en into consideration during shafting alignment calculation at some amples to .