Handbook Of Shaft Alignment Episode 3 Part 3 ppsx

7. Using the optical micrometer, measure the positions of the targets at the near and far ends of the far cylinder in the vertical and sideways directions. Study and perform the information in Figure 19.22. Record the information. TOPT OPTOPT OP Top Top One-half of the original horizontal offset One-half of the original vertical offset Initial position of target Position of target after moving horizontally and vertically inside the cylinder Step 4. Adjust the position of the target inside the bore of the cylinder by alternately loosening and tightening the target fixture adjustment screws at the 12 and 6 o’ clock position to place the target half the total vertical offset distance measured in step 3 above. Adjust the position of the target inside the bore of the cylinder by alternately loosening and tightening the adjustment screws at the 3 and 9 o’clock position to place the target half the total lateral offset distance measured in step 3 above as shown in the figure below. FIGURE 19.19 Step 4 for centering a target in a cylinder. TOPT OP TOPT OP TOPT OP TOPT OP TOPT OP TOPT OP Initial position of target Position of target after the target was moved horizontally and vertically inside the cylinder Top Top Observed position of target afte r adjusting vertical and lateral tangent screws on ji g t ransit Step 5. Adjust the vertical and lateral tangent screws on the jig transit to center the telescope crosshairs in the center of the bore target as shown in the figure below. Step 6. Repeat step 3 though step 5 until their target stays centered in the telescope crosshairs through 3608 of rotation. FIGURE 19.20 Step 5 and step 6 for centering a target in a cylinder. Piotrowski / Shaft Alignment Handbook, Third Edition DK4322_C019 Final Proof page 630 26.9.2006 8:43pm 630 Shaft Alignment Handbook, Third Edition 8. If the targets at the near and far ends of the far cylinder are not coincident (in line) with the targets at the near and far ends of the near cylinder, position either the near or far cylinder to bring the bore centers into alignment. Refer to the ‘‘correcting the misalign- ment’’ procedure below and study Figure 19.23 and Figure 19.24. 19.5 BUCKING IN PROCESS 1. Center the bore targets at both ends of the cylinder as shown in Figure 19.21. Measure the distance between the bore targets and the distance from the near target to the center of the jig transit (i.e., where it rotates through its azimuth or Z-axis). Focus on the far target and using the tangent screws, center the telescope crosshairs on the target. Focus on the near target and observe its position with respect to the telescope crosshairs. If you are lucky the near target is centered in the telescope crosshairs. Use optical micrometer to measure the offset at this target Step 1 Step 2 Step 3 Adjust tangent screws to zero on this target Near to far target distance Near target to transit distance Translation distance needed for correction = (Near to far target distance + near target to transit distance) * (offset at near target) Near to far target distance New position Original position Translate the jig transit to here Translation distance needed for correction Offset at near target Rotate the jig transit to aim at the center of the far target then focus back to see if the near target is also centered FIGURE 19.21 Bucking in your line of sight to the centerline of the bore of the cylinder. Piotrowski / Shaft Alignment Handbook, Third Edition DK4322_C019 Final Proof page 631 26.9.2006 8:43pm Bore Alignment 631 OK, so much for dumb luck. The near and far targets are not directly in line with each other. What you have to do now is translate the entire jig transit in the sideways direction and rotate the jig transit through its azimuth (Z) axis to align the vertical crosshairs of the telescope with the vertical paired lines on the near target. Similarly, you have to raise or lower the jig transit in the vertical direction using the precision lift mechanism and plunge (i.e., pitch) the jig transit through its pivoting (X) axis to align the vertical crosshairs of the telescope with the horizontal paired lines on the near target. Now there are two ways to do this: trial and error and mathematics. Both work, mathematics just happens to be slightly faster but requires a little bit of number crunching. Plug the scale target reading at the near target and the distances into the formula to obtain the necessary translation distances. 2. Translate (i.e., move) the entire jig transit in the sideways direction to the amount you calculated in the equation. You can either use the rotary indicator wheel on the translation table where the scope is mounted or you can focus the scope on the near target, set the optical micrometer to the desired lateral translation distance (assuming it is under 100 mils), and begin translating the scope until the crosshairs line up on the near target’s horizontal and vertical paired lines. Raise (or lower) the entire jig transit in the vertical direction the amount you calculated in the equation by adjusting the vertical lift mechanism. You can focus the 28 mils to the right 18 mils high 34 mils to the left 52 mils high Telescope crosshairs are bucked into the bore centerline of the near cylinder when these measurement were taken Near target in far cylinder Far target in far cylinder FIGURE 19.22 Measuring the amount of misalignment of the near and far targets in the far cylinder. Piotrowski / Shaft Alignment Handbook, Third Edition DK4322_C019 Final Proof page 632 26.9.2006 8:43pm 632 Shaft Alignment Handbook, Third Edition Scale : 10 in. 10 mils Near cylinder Far cylinder-far support Far cylinder Bore target position Bolting plane 52 mils high 18 mils high Far cylinder-far target Far cylinder-near target Far cylinder-near support Near cylinder-near support Near cylinder-far support Side view Up Overlay/final desired alignment line raise up 6 mils Raise up 14 mils FIGURE 19.23 Side view alignment model with one possible alignment solution shown. Piotrowski / Shaft Alignment Handbook, Third Edition DK4322_C019 Final Proof page 633 26.9.2006 8:43pm Bore Alignment 633 Scale: 10 in. 10 mils Near cylinder Far cylinder-far support Far cylinder Bore target position Bolting plane 34 mils to the left 28 mils to the right Far cylinder-far target Far cylinder-near target Far cylinder-near support Near cylinder-near support Near cylinder-far support Top view Right Overlay / final desired alignment line Move 22 mils left Move 14 mils left Move 15 mils right Move 23 mils left FIGURE 19.24 Top view alignment model with one possible alignment solution shown. Piotrowski / Shaft Alignment Handbook, Third Edition DK4322_C019 Final Proof page 634 26.9.2006 8:43pm 634 Shaft Alignment Handbook, Third Edition scope on the near target, set the optical micrometer to the desired vertical translation distance (assuming it is under 100 mils), and begin translating the scope until the crosshairs line up on the near target’s horizontal and vertical paired lines. 3. Once you have translated the scope you must now rotate the scope through its azimuth axis so your vertical crosshair lines back up with the vertical paired lines on the near target. Similarly, you now must plunge or pitch the scope through its X-axis so your horizontal crosshair lines up with the horizontal paired lines on the near target. If everything works well, the telescope’s line of sight should be centered at the near and far targets. If not, repeat step 1 through step 3 until the telescope crosshairs and the centers of both targets are in line with each other. At this point, the line of sight of the pivoting scope on the jig transit is parallel to the bore centerline of the cylinder. 19.6 CORRECTING THE MISALIGNMENT Once the bore targets were centered in the far cylinder and the telescope’s line of sight was bucked back into the centerline of the bore of the near cylinder, measurements were taken at the near and far targets of the far cylinder. To help visualize the misalignment between the two cylinders and assist in correcting the misalignment condition, construct side view and top view alignment models. As shown in Figure 19.22, assume that the following measurements were taken at the far cylinder targets: Near target: 18 mils high and 28 mils to the right Far target: 52 mils high and 34 mils to the left Figure 19.23 shows an exaggerated misalignment condition between the near and far cylinders in the side view (up or down direction). Figure 19.24 shows an exaggerated misalignment condition between the near and far cylinders in the top view (left or right direction). Notice that the target positions and bolting plane positions have been accurately scaled on the graph paper from left to right and the bore centerline of the far cylinder has been accurately scaled from top to bottom on the graph (see scale factors in lower left hand corner). Now a straight line can be drawn on top of the graph and the cylinders can be moved to that overlay or final desired alignment line. 19.7 LASER BORE ALIGNMENT SYSTEMS Laser–detector systems as shown in Figure 19.25 through Figure 19.30 have been developed to accomplish the task of bore alignment. If you have not already done so, you might want to review the information on lasers and photodiode detectors in Chapter 6 to get a basic understanding of how these components work. The principles of bore alignment with laser–detector systems are virtually identical to the process using optical alignment equipment explained in this chapter. The laser beam is substi- tuted for the visual line of sight established with a jig transit. Rather than visually observing a sighting target placed in the center of a hollow cylinder, a photodiode is centered in the cylinder and a cable transmits the position of the laser beam on the surface of the detector. Piotrowski / Shaft Alignment Handbook, Third Edition DK4322_C019 Final Proof page 635 26.9.2006 8:43pm Bore Alignment 635 FIGURE 19.25 D630 Extruder system. (Courtesy of Damalini, Molndal, Sweden. With permission.) FIGURE 19.26 D630 Linebore system. (Courtesy of Damalini, Molndal, Sweden. With permission.) Piotrowski / Shaft Alignment Handbook, Third Edition DK4322_C019 Final Proof page 636 26.9.2006 8:43pm 636 Shaft Alignment Handbook, Third Edition FIGURE 19.27 Fixturlaser Extruder system. (Courtesy of Fixturlaser, Molndal, Sweden. With permission.) FIGURE 19.28 Fixturlaser Centering system. (Courtesy of Fixturlaser, Molndal, Sweden. With permission.) Piotrowski / Shaft Alignment Handbook, Third Edition DK4322_C019 Final Proof page 637 26.9.2006 8:43pm Bore Alignment 637 FIGURE 19.29 Pru ¨ ftechnik Boralign system. (Courtesy of Pruftechnik, Ismaning, Germany. With permission.) FIGURE 19.30 Pru ¨ ftechnik Centralign system. (Courtesy of Pruftechnik, Ismaning, Germany. With permission.) Piotrowski / Shaft Alignment Handbook, Third Edition DK4322_C019 Final Proof page 638 26.9.2006 8:43pm 638 Shaft Alignment Handbook, Third Edition 20 Parallel Alignment Chapter 18 covered alignment of V-belt-driven equipment. As you observed, the goal of aligning belts and sheaves is to get the driver shaft parallel to the driven shaft and the belts to track straight in the sheaves. To accomplish this task, the outer surfaces of the sheaves or the grooves of the sheave itself were used as the reference positions. The assumption is that the outer surfaces of the sheaves or the grooves of the sheave itself are perfectly perpendicular to its centerline of rotation. To verify the perpendicularity of the sheave to its shaft, face runout measurements are taken as shown in Figure 18.13 and Figure 18.15. Once we are sure that the sheaves are indeed perpendicular to their centerlines of rotation, we can then use straight edges, strings, wires, or laser beams to align the sheaves, bringing the two shafts into a parallel position. It seems cumbersome to use the sheaves as the reference positions but the shafts are typically buried inside the machine casings, making it virtually impossible to use the shafts themselves to measure from. If only the whole length of both shafts were exposed! Well, in some cases, they are. There are drive systems in industry that encompass a series of cylinders, shafts, or rolls where they must be positioned so they are parallel to each other. Examples of this are frequently found in the paper, plastic, printing, and steel industry. 20.1 ROUGH ALIGNMENT OF PARALLEL ROLLS As a quick review, Figure 20.1 shows the coordinate system and terminology used in aligning cylinders or rolls. The goal in aligning rolls is to get all rolls so that their individual y–z planes are parallel or coplanar and their x–z planes are parallel or coplanar. Perhaps the simplest method of measuring roll parallelism is to use a standard tape measure. Effectively you wrap the tape measure around each roll, once at one end, record the distance around and between the two rolls there, then again at the other end as shown in Figure 20.2 and Figure 20.3. Compare the distance at the near and far ends. If the measure- ments are the same, assuming both rolls are level with respect to gravity, the centerlines of rotation of the rolls are parallel to each other. If however, the rolls are not level with respect to gravity, their y–z planes may be parallel, but the centerlines of rotation may not be parallel. Figure 20.4 shows how the two tape measurement distances at the near and far end can be the same but the centerlines of rotation of the rolls might not be parallel. Bear in mind that the x–z plane does not have to be referenced to gravity, that is, the x–z plane does not necessarily have to be level. Remember, level and aligned do not mean the same thing. It is nice and convenient that the rolls are level but they do not have to be. If their slopes are the same (i.e., the x–z plane is not level, but at a fixed angle), placing the rolls parallel to each other is still achievable. Piotrowski / Shaft Alignment Handbook, Third Edition DK4322_C020 Final Proof page 639 27.9.2006 1:30am 639 [...]... transit square on its stand so that your line of sight is slightly to one side of one of the shafts (or roll) as shown in Figure 20.9 This transit will be referred to as the measurement transit Piotrowski / Shaft Alignment Handbook, Third Edition DK 432 2_C020 Final Proof page 6 43 27.9.2006 1 :30 am Parallel Alignment 6 43 FIGURE 20.6 Jig transit (Courtesy of Brunson Instruments Co., Kansas City, MO With... telescope’s line of sight is parallel to the shaft (or roll) as shown in Figure 20.10 and Figure 20.11 Piotrowski / Shaft Alignment Handbook, Third Edition DK 432 2_C020 Final Proof page 644 27.9.2006 1 :30 am 644 Shaft Alignment Handbook, Third Edition Line of sight Optical scale target A Optical scale target B Upper shaft (or roll) Optical jig transit or universal transit square Y Z Lower shaft (or roll)... Chapter 13, Chapter 14, and Chapter 17 For this particular example, we will assume that there is no off-line to running (OL2R) machinery movement in any of the components FIGURE 20.21 FixturLaser roll system (Courtesy of FixturLaser, Molndal, Sweden With permission.) Piotrowski / Shaft Alignment Handbook, Third Edition DK 432 2_C020 Final Proof page 654 27.9.2006 1 :30 am 654 Shaft Alignment Handbook, ... compared to the dozens of rolls you have to align on your machines The power of the alignment modeling techniques comes from the fact that you can put as many pieces of machinery on the model as you want In some cases, you may need some large sheets of graph paper Piotrowski / Shaft Alignment Handbook, Third Edition DK 432 2_C020 Final Proof page 656 27.9.2006 1 :30 am 656 Shaft Alignment Handbook, Third Edition... of universal transit square Translation distance Translation distance = (reading at scale E − reading at scale F) 3 scope to E E to F FIGURE 20.10 Top view of sighting the roll in the lateral direction Piotrowski / Shaft Alignment Handbook, Third Edition DK 432 2_C020 Final Proof page 646 27.9.2006 1 :30 am 646 Shaft Alignment Handbook, Third Edition Scale target F Scale target E Scale target E Line of. .. 20.1, the position of a shaft or roll can be described by its pitch, roll, and yaw positions For shafts or rolls to be parallel, they would share the same roll, pitch, and yaw Pentaprism Laser FIGURE 20.18 Laser beam exits at a precise 908 angle with a pentaprism Piotrowski / Shaft Alignment Handbook, Third Edition DK 432 2_C020 Final Proof page 652 27.9.2006 1 :30 am 652 Shaft Alignment Handbook, Third... measured and stored into memory Piotrowski / Shaft Alignment Handbook, Third Edition DK 432 2_C020 Final Proof page 6 53 27.9.2006 1 :30 am Parallel Alignment 6 53 FIGURE 20.20 Damalini Model D670 roll parallelism measurement system (Courtesy of Damalini, Molndal, Sweden With permission.) 20.7 ALIGNING ROLLS AND THEIR DRIVES—SAMPLE PROBLEM Figure 20 .32 shows a side view of two motors flexibly connected to drive... (Courtesy of Hamar Laser Instrument Co., Danbury, CT With permission.) FIGURE 20.28 Hamar Model T-212 4 axis target (Courtesy of Hamar Laser Instrument Co., Danbury, CT With permission.) Piotrowski / Shaft Alignment Handbook, Third Edition DK 432 2_C020 Final Proof page 658 27.9.2006 1 :30 am 658 Shaft Alignment Handbook, Third Edition FIGURE 20.29 Hamar Model P-405 optical square (Courtesy of Hamar Laser... rolls at the far end Piotrowski / Shaft Alignment Handbook, Third Edition DK 432 2_C020 Final Proof page 641 27.9.2006 1 :30 am 641 Parallel Alignment Side view End view FIGURE 20.4 Centerlines of rotation are parallel in the y–z plane but skewed in the x–z plane 20.2 USING OPTICAL ALIGNMENT EQUIPMENT FOR ROLL PARALLELISM The extreme accuracy and versatility of optical alignment equipment makes it ideal... Danbury, CT With permission.) Piotrowski / Shaft Alignment Handbook, Third Edition DK 432 2_C020 Final Proof page 659 27.9.2006 1 :30 am Parallel Alignment 659 ¨ FIGURE 20 .30 Pruftechnik Paralign system (Courtesy of Pruftechnik, Ismaning, Germany With permission.) FIGURE 20 .31 Paralign internals showing the three ring laser gyroscope in orthogonal positions (Courtesy of Pruftechnik, Ismaning, Germany With . amount of misalignment of the near and far targets in the far cylinder. Piotrowski / Shaft Alignment Handbook, Third Edition DK 432 2_C019 Final Proof page 632 26.9.2006 8:43pm 632 Shaft Alignment Handbook, . cylinder. Piotrowski / Shaft Alignment Handbook, Third Edition DK 432 2_C019 Final Proof page 630 26.9.2006 8:43pm 630 Shaft Alignment Handbook, Third Edition 8. If the targets at the near and far ends of the. position of the laser beam on the surface of the detector. Piotrowski / Shaft Alignment Handbook, Third Edition DK 432 2_C019 Final Proof page 635 26.9.2006 8:43pm Bore Alignment 635 FIGURE 19.25 D 630