ALIGNMENT POROS
SHAFT ALIGNMENT Definisi shaft alignment ? Adjustment posisi relatif dari dua poros, ex. motor (driver & pompa (driven). Pengaturan posisi center pada kondisi operasi normal.
EFEK MISALIGNMENT ROTATING MACHINERY
Distorsi poros (Shaft) Konsumsi energi meningkat Mengurangi umur bantalan Kerusakan seal Shut down tidak terjadwal.
Kondisi Aligned
Misaligned seal terbuka kebocoran dan kontaminasi
JENIS MISALIGNMENT
Parallel misalignment Angular misalignment
IDENTIFIKASI MISALIGNMENT Inspeksi peralatan
Kerusakan awal pada bearing, seal, shaft, or coupling failures.
Temperatur tinggi pada bearings atau minyak pelumass
Kebocoran yang berlebihan pada seal
Longgar baut pengikat kaki
Longgar atau rusak baut pada kopling
Pecah atau rusak karet pada fleksibel kopling
INSPEKSI PERALATAN
Kerusakan tidak wajar pada kopling. Retaknya poros pada bagian bearing dekat kopling Penambahan pelumas yang berlebihan
DATA ANALISA VIBRATION Bentuk Vibrasi pada misalignment : Vibrasi pada arah aksial. High vibration at 1xTS or 2xTS in the spectrum. Signifikasi fase getaran 180 derajat
ANGULAR MISALIGNMENT Spectrum
Phase
High axial vibration both in 1X and 2X rpm 180° Out-of-phase across the coupling (axial – axial).
PARALLEL MISALIGNMENT Spectrum
Phase
High radial vibration, 2x rpm often larger than 1x rpm, but its height relative to 1x rpm is often dictated by coupling type and construction 180° Out-of-phase across the coupling (horizontal – horizontal or vertical – vertical)
INFRARED THERMOGRAPH
FLEXIBLE COUPLING
FONDASI DAN BASEPLATE
“Bowed” baseplate
“Skewed” baseplate
PREALIGNMENT Sebelum melakukan alignment Kondisi fondasi. Kerusakan bearings, shafts, seals, couplings dll. Poros bengkok Softfoot
KOREKSI SOFT FOOT
Soft foot = gap antara mesin dengan fondasi Diperbaiki sebelum alignment Soft foot menyebabkan tegangan pada baut dan bearing
KOREKSI SOFTFOOT
Stress lines due to softfoot
Pre-loading bearing due to softfoot
KOREKSI SOFTFOOT Bentuk umum softfoot
KORESKSI SOFT FOOT
Dial Indicator Install a dial indicator on the foot and watching the movement as you loosen the hold down bolt. Laser Method •Mount the laser on the machine shaft on either side of coupling •Loosen individual bolt and retighten •Read the live display
METODE ALIGNMENT
Straight edge and feeler gauge Face & Rim Reverse Indicator
STRAIGHT EDGE
FEELER GAUGE
FACE & RIM PROSEDUR 1. Attached bracket firmly to one shaft and position
2. 3. 4. 5.
indicators on face and periphery of other shaft Zero the indicators at the 12 o’clock position Rotate slowly the shaft and bracket arrangement through 90 degrees interval stopping at the 3, 6 & 9 o’clock positions. Record each reading (+ or -) Return to the 12 o’clock position to see if the indicators rezero Repeat steps 2 through 4 to verify the first of readings
FACE & RIM
REVERSE INDICATOR PROSEDUR 1. Attached bracket(s) firmly to one shaft(s) and position 2. 3.
4. 5. 6.
indicator(s) on face and periphery of other shaft(s) Zero the indicator(s) at the 12 o’clock position Rotate slowly the shaft and bracket arrangement through 90 degrees interval stopping at the 3, 6 & 9 o’clock positions. Record each reading (+ or -) Return to the 12 o’clock position to see if the indicator(s) re-zero Repeat steps 2 through 4 to verify the first of readings If one bracket was used, mount bracket on other shaft and repeat steps 1 through 5
REVERSE INDICATOR
DIAL INDICATOR MOUNTING Mounting buruk
The stem does not perpendicular to the reading surface
Mounting benar
DIAL INDIKATOR
Dial tidak menyentuh
VALIDASI PEMBACAAN
kiri + kanan = atas + bawah
PERPINDAHAN PERALATAN
Vertical movement
Horizontal movement
Axial movement
CARA PEMBACAAN
Apabila harga pergerakan dial dari arah jam 12 ke jam 6 Aktuak offset = ½ selish indikatir pada dial
Axial view of the shaft
CARA MEMBACA
Solusi matematis (+) = the unit has to be raised (add shim) for vertical movement or moved to the left for horizontal movement (-) = the unit has to be lowered or moved to the right
CARA PEMBACAAN
Solusi matematis (+) = the unit has to be raised (add shim) for vertical movement or moved to the left for horizontal movement (-) = the unit has to be lowered or moved to the right
ALIGNMENT (Metode graphis)
ALIGNMENT (Metode graphis)
Position of the driven shaft when the bottom reading is negative (-)
ALIGNMENT (Metode graphis)
Position of the driven shaft when the bottom reading is positive (+)
ALIGNMENT (Metode graphis)
Position of the driver shaft when the bottom reading is negative (-)
ALIGNMENT (Metode graphis)
Position of the driver shaft when the bottom reading is positive (+)
LASER ALIGNMENT
LASER ALIGNMENT
LASER ALIGNMENT
LASER ALIGNMENT Keuntungan Cepat Panjang poros sampai 20 m Ketelitian tinggi Perhitungan otomatis Pengaruh temp. kecil Kekurangan Dikalibrasi secara periodik
TOLERANSI ALIGNMENT
CSI Recommended Tolerances for Shaft Alignment
Fixturlaser Recommended Tolerances for Shaft Alignment
LASER ALIGNMENT
Ludeca Recommended Tolerances for Shaft Alignment
John Piotrowski
