A Practical Guide to Shaft Alignment phần 5

Phương pháp liên kết - chỉ số quay số Ngược lại phương pháp chỉ thị - Bằng cách tính toán Phương pháp chỉ số đảo ngược của sự liên kết là phương pháp chỉ số liên kết quay số tiên tiến nhất, như vậy nó là khuyến cáo của Viện Dầu khí Mỹ (API 686) là phương pháp quay số chỉ số liên kết ưa thích. | Alignment methods - Dial indicators Reverse indicator method - By calculation The reverse indicator method of alignment is the most advanced dial indicator alignment method as such it is recommended by the American Petroleum Institute API 686 as the preferred dial indicator alignment method. Reverse indicator alignment takes its name from the positions of the two radial indicators opposing one another on the opposite coupling halves. A traditional indicator set up is shown above. Once mounted the two shafts are rotated together and the dials are read at 12 00 3 00 6 00 and 9 00. Formulas for calculating Reverse indicator alignment For such setups the misalignment at the coupling center is as follows VO S6-S0 SS 2 - S6-S0 SS M6-M0-MS C 2D VA S6-S0 SS M6-M0-MS 2D HO S9-S3 2 - S9-S3 M9-M3 C 2D HA S9-S3 M9-M3 2D 41 2002 PRUFTECHNIK LTD. Alignment methods - Dial indicators Where S0 Left rim reading at 12 o clock S3 Left rim reading at 3 o clock S6 Left rim reading at 6 o clock S9 Left rim reading at 9 o clock M0 Right rim reading at 12 o clock M3 Right rim reading at 3 o clock M6 Right rim reading at 6 o clock M9 Right rim reading at 9 o clock d Distance between left and right indicators c Distance between left indicator and coupling center SS sag of left rim indicator 1 MS sag of right rim indicator 1 1 these values can be positive or negative The corrections at the right machine feet can be calculated as follows Shim left feet VA - sL - VO Shim right feet VA - sR - VO Positive result means add shim negative result means remove shim. Shim left feet VA -sL - VO Shim right feet VA -sR - VO Positive result means move towards 3 o clock negative means move toward 9 o clock. sL Distance from the coupling center to left feet of right m ce sR Distance from the coupling center to right feet of right m ce. If the dial indicators are set to zero at 12 o clock and then read at 6 o clock the shim calculation are as follows HO S9-S3 2 - S9-S3 M9-M3 C 2D HA S9-S3 M9-M3 2D 42 2002 .