Carrier 17EX Start-up, Operation And Maintenance Instructions Manual

Also see for 17EX Series: Start up & operation manual Start-up, operation and maintenance instructions

Contents

Chiller AlignmentALIGNMENT METHODS — There are several establishedprocedures for aligning shafts. The dial indicator method ispresented here since it is considered to be one of the mostaccurate and reliable. Another faster and easier method foralignment involves using laser alignment tools and comput-ers. Follow the laser tool manufacturer’s guidelines whenusing the laser technique.Where job conditions such as close-spaced shafts prohibitthe use of dial indicators for coupling face readings, otherinstruments such as a taper gage may be used. The same pro-cedures described for the dial indicator may be used with thetaper gage.Shafts placed in perfect alignment in the non-operating(cold) condition will always move out of alignment to someextent as the chiller warms to operating temperature. In mostcases, this shaft misalignment is acceptable for the initial run-inperiod before hot check and alignment can be made (see HotAlignment Check section, page 61).NOTE: The physical configuration of the 17FX compressormakes the oil sump temperature a more significant factor inalignment than the suction and discharge temperatures. There-fore, warm the sump oil to operating temperature (approxi-mately 140 F [60 C]), if possible, before beginning align-ment procedures.General1. Final shaft alignment must be within .002-in. (.05-mm)TIR (Total Indicated Runout) in parallel. Angular align-ment must be within 0.00033 inches per inch of traverse(0.00033 mm per mm of traverse) across the coupling face(or inch of indicator swing diameter) at operating tem-peratures. For example, if a bracket-mounted indicatormoves through a 10-in. diameter circle when measuringangular misalignment, the allowable dial movement willbe 10 times 0.00033 for a total of 0.0033 in. (0.0033 mm).2. Follow the alignment sequence specified in the NearFinal Alignment section.3. All alignment work is performed on gear and drive equip-ment. Once the compressor is bolted in a perfectly levelposition and is piped to the cooler and condenser, it mustnot be moved prior to hot check.4. All alignment checks must be made with the equipmenthold-down bolts tightened.5. In setting dial indicators on zero and when taking read-ings, both shafts should be tight against their respectivethrust bearings.6. The space between coupling hub faces must be held tothe dimensions in Fig. 29 and 30.7. Accept only repeatable readings.High Speed Coupling Alignment1. Move the gear with the coupling attached into alignmentwith the compressor coupling. The compressor must bein the thrust position and the gear must be centered be-tween the thrust collars when determining gear positionrelative to the compressor. Adjust the jackscrews to reachclose alignment. Follow the procedures outlined in theCorrecting Angular Misalignment and Correcting Paral-lel Misalignment sections.2. A 5-in. long spacer hub is supplied between the gear andcompressor. Maintain the exact hub-to-hub distance speci-fied in Fig. 29.3. Where the shaft ends are very close, a taper gage may beused in place of the dial indicator.4. Get the gear alignment as close as possible by using thejackscrew adjustment.Low Speed Coupling Alignment1. Move the motor with the coupling attached into align-ment with the gear coupling. The motor must be in itsmechanical center and the gear must be centered betweenthe thrust collars when determining the motor positionrelative to the gear. Adjust the jackscrews to reach closealignment. Follow the procedure outlined in the Correct-ing Angular Misalignment and Correcting Parallel Mis-alignment sections.2. Maintain the exact hub-to-hub distance as specified inFig. 30.3. Where the shaft ends are very close, a taper gage may beused in place of the dial indicator.4. Get the motor alignment as close as possible by using thejackscrew adjustment.NOTE: The drive shaft end-float at final drive position mustnot allow the coupling hub faces to make contact or the cou-pling shroud to bind.PRELIMINARY ALIGNMENT — To get within dial indi-cator range, roughly align the equipment as shown in Fig. 37and as described below.Place a straight edge across the OD of one coupling to theOD of the other. Measure the gap between the straight edgeand the OD of the second coupling with a feeler gage. Then,by adding or removing shims at each corner, raise or lowerthe equipment by the measured amount.In a similar manner, measure the shaft offset from side toside and jack the equipment over as required to correct.NEAR FINAL ALIGNMENT — Once the chiller compo-nents are within dial indicator range, the adjustments for mis-alignment should be made in a specific sequence. The fourpositions of alignment described below are arranged in therecommended order.1. Angular in elevation — This alignment is adjustedwith shims and is not readily lost in making the otheradjustments.Fig. 37 — Checking Preliminary Alignment71