Sebuah viskometer (juga disebut viscosimeter) adalah alat yang digunakan untuk mengukur
viskositas dari suatu fluida. Untuk cairan dengan viskositas yang bervariasi dengan kondisi aliran, alat yang disebut Rheometer yang digunakan. Alat ukur kekentalan hanya mengukur satu kondisi di bawah aliran.
Secara umum, baik cairan tetap diam dan objek bergerak melalui itu, atau objek stasioner dan cairan bergerak melewatinya. Hambatan yang disebabkan oleh gerakan relatif dari cairan dan permukaan adalah ukuran viskositas. Kondisi aliran harus memiliki nilai yang cukup kecil bilangan Reynolds untuk itu menjadi aliran laminar.
Pada 20,00 derajat Celcius viskositas air adalah 1,002 MPa ° S dan viskositas kinematik nya (rasio viskositas kepadatan) adalah 1,0038 mm2 / s. Nilai-nilai ini digunakan untuk kalibrasi jenis tertentu viskometer.
Secara umum, baik cairan tetap diam dan objek bergerak melalui itu, atau objek stasioner dan cairan bergerak melewatinya. Hambatan yang disebabkan oleh gerakan relatif dari cairan dan permukaan adalah ukuran viskositas. Kondisi aliran harus memiliki nilai yang cukup kecil bilangan Reynolds untuk itu menjadi aliran laminar.
Pada 20,00 derajat Celcius viskositas air adalah 1,002 MPa ° S dan viskositas kinematik nya (rasio viskositas kepadatan) adalah 1,0038 mm2 / s. Nilai-nilai ini digunakan untuk kalibrasi jenis tertentu viskometer.
Tabung U Alat ukur kekentalan
Perangkat ini juga dikenal sebagai Alat ukur kekentalan gelas kapiler atau Alat ukur kekentalan Ostwald, dinamai Wilhelm Ostwald. Versi lain adalah viskometer Ubbelohde, yang terdiri dari tabung kaca berbentuk U dipegang vertikal dalam sebuah bak suhu terkontrol. Dalam salah satu lengan U adalah bagian vertikal menanggung sempit tepat (kapiler). Di atas ini adalah bohlam, dengan itu adalah bohlam lain lebih rendah di lengan lainnya. Dalam penggunaan, cairan ditarik ke dalam bola atas dengan pengisapan, kemudian dibiarkan mengalir melalui kapiler ke dalam bola rendah. Dua tanda (satu di atas dan satu di bawah bola atas) menunjukkan volume yang diketahui. Waktu yang dibutuhkan untuk tingkat cairan untuk lulus antara tanda sebanding dengan viskositas kinematik. Sebagian besar unit komersial disediakan dengan faktor konversi, atau dapat dikalibrasi oleh cairan sifat yang dikenal.
Waktu yang dibutuhkan untuk tes cairan mengalir melalui kapiler dengan diameter yang dikenal dari suatu faktor tertentu antara dua titik ditandai diukur. Dengan mengalirkan waktu yang diambil oleh faktor viskometer tersebut, viskositas kinematik diperoleh.
Alat ukur kekentalan tersebut juga diklasifikasikan sebagai aliran langsung atau arus balik. Alat ukur kekentalan arus balik memiliki reservoir di atas tanda-tanda dan aliran langsung adalah mereka dengan reservoir bawah tanda-tanda. Klasifikasi seperti ada sehingga tingkat dapat ditentukan bahkan ketika cairan buram atau pewarnaan diukur, jika tidak cairan akan menutupi tanda-tanda dan membuat tidak mungkin untuk mengukur tingkat waktu melewati tanda. Hal ini juga memungkinkan viskometer untuk memiliki lebih dari 1 set tanda untuk memungkinkan untuk waktu langsung dari waktu yang dibutuhkan untuk mencapai angka 3, sehingga menghasilkan 2 timing dan memungkinkan untuk perhitungan berikutnya Determinability untuk memastikan hasil yang akurat.
Piston jatuh Viskometer
Norcross In-Tank Viskometer
Norcross In-Tank Viskometer
Juga dikenal sebagai viskometer Norcross karena penemu, Austin Norcross. Prinsip pengukuran viskositas dalam industri perangkat kasar dan sensitif didasarkan pada piston dan silinder perakitan. Piston secara berkala dibangkitkan oleh mekanisme mengangkat udara, menggambar materi yang diukur turun melalui pembersihan (kesenjangan) antara piston dan dinding silinder ke dalam ruang yang terbentuk di bawah piston seperti yang dimunculkan. Perakitan tersebut kemudian biasanya digelar untuk beberapa detik, lalu dibiarkan jatuh oleh gravitasi, mengusir sampel keluar melalui jalan yang sama yang masuk, menciptakan efek geser pada cairan diukur, yang membuat viskometer ini sangat sensitif dan baik untuk mengukur thixotropic cairan tertentu. Waktu jatuh adalah ukuran viskositas, dengan jarak antara piston dan silinder dalam membentuk lubang pengukuran. Controller viskositas mengukur waktu jatuh (Time-of-jatuh detik menjadi ukuran viskositas) dan menampilkan nilai viskositas yang dihasilkan. Controller dapat mengkalibrasi waktu-of-jatuh nilai detik cangkir (dikenal penghabisan cangkir), SSU atau centipoise.
Industri menggunakan sangat populer karena kesederhanaan, pemeliharaan keterulangan, rendah dan umur panjang. Jenis pengukuran tidak terpengaruh oleh laju aliran atau getaran eksternal. Prinsip operasi dapat diadopsi untuk kondisi yang berbeda, sehingga ideal untuk lingkungan pengendalian proses.
Viskometer Piston Osilasi
Kadang-kadang disebut sebagai elektromagnetik Viskometer atau EMV viskometer, diciptakan di Viskositas Cambridge pada tahun 1986. Sensor (lihat gambar di bawah) terdiri dari ruang pengukuran dan piston magnetis dipengaruhi. Pengukuran diambil dimana sampel pertama kali diperkenalkan ke ruang pengukuran termal terkendali di mana piston berada. Elektronik drive piston ke gerak berosilasi dalam ruang pengukuran dengan medan magnet dikendalikan. Sebuah tegangan geser dikenakan pada cairan (atau gas) karena perjalanan piston dan viskositas ditentukan dengan mengukur waktu tempuh piston. Parameter konstruksi untuk jarak annular antara piston dan ruang pengukuran, kekuatan medan elektromagnetik, dan jarak perjalanan piston digunakan untuk menghitung viskositas menurut UU Viskositas Newton.
Piston berosilasi Viskometer Skema Lihat
Teknologi Piston Viskometer Osilasi telah diadaptasi untuk viskositas sampel kecil dan mikro-sampel pengujian viskositas dalam aplikasi laboratorium. Hal ini juga telah diadaptasi untuk mengukur viskositas pengukuran tekanan tinggi dan suhu tinggi viskositas dalam kedua lingkungan laboratorium dan proses. Sensor viskositas telah ditingkatkan untuk berbagai macam aplikasi industri seperti Alat ukur kekentalan ukuran kecil untuk digunakan pada kompresor dan mesin, aliran-melalui Alat ukur kekentalan untuk dip proses pelapisan, in-line Alat ukur kekentalan untuk digunakan dalam kilang, dan ratusan aplikasi lain. Perbaikan dalam sensitivitas dari elektronik modern, merangsang pertumbuhan Osilasi popularitas Piston Viskometer dengan laboratorium akademis menjelajahi viskositas gas.
Alat ukur
kekentalan vibrasi
Alat ukur kekentalan getaran tanggal kembali ke instrumen Bendix tahun 1950, yang merupakan kelas yang beroperasi dengan mengukur redaman osilasi elektromekanis resonator dibenamkan dalam fluida yang viskositas akan ditentukan. Resonator umumnya berosilasi pada torsi atau melintang (sebagai balok kantilever atau garpu tala). Semakin tinggi viskositas, semakin besar redaman yang dikenakan pada resonator. Redaman resonator yang dapat diukur dengan salah satu dari beberapa metode:
Mengukur input daya yang diperlukan untuk menjaga osilator bergetar pada amplitudo konstan. Semakin tinggi viskositas, daya lebih banyak dibutuhkan untuk mempertahankan amplitudo osilasi.
Mengukur waktu peluruhan osilasi setelah eksitasi dimatikan. Semakin tinggi viskositas, semakin cepat meluruh sinyal.
Mengukur frekuensi dari resonator sebagai fungsi dari sudut fase antara bentuk gelombang eksitasi dan respons. Semakin tinggi viskositas, semakin besar perubahan frekuensi untuk perubahan fasa diberikan.
Instrumen getaran juga menderita dari kurangnya lapangan geser didefinisikan, yang membuatnya cocok untuk mengukur viskositas cairan yang aliran perilaku tidak diketahui sebelum tangan.
Alat ukur kekentalan getar adalah sistem industri kasar digunakan untuk mengukur viskositas dalam kondisi proses. Bagian aktif dari sensor adalah batang bergetar. Amplitudo getaran bervariasi sesuai dengan viskositas cairan di mana batang terendam. Ini meter viskositas cocok untuk mengukur cairan menyumbat dan cairan viskositas tinggi, termasuk mereka dengan serat (hingga 1.000 Pa ° S). Saat ini, banyak industri di seluruh dunia pertimbangkan Alat ukur kekentalan untuk menjadi sistem yang paling efisien yang dapat digunakan untuk mengukur viskositas dari berbagai macam cairan; sebaliknya, Alat ukur kekentalan rotasi membutuhkan perawatan lebih, tidak mampu untuk mengukur penyumbatan cairan, dan memerlukan kalibrasi sering setelah intensif digunakan. Alat ukur kekentalan getar tidak memiliki bagian yang bergerak, tidak ada bagian yang lemah dan bagian sensitif sangat kecil. Bahkan cairan yang sangat dasar atau asam dapat diukur dengan menambahkan lapisan pelindung atau dengan mengubah bahan sensor untuk bahan seperti 316L, SUS316, atau email
Alat ukur kekentalan putaran
Alat ukur kekentalan rotasi menggunakan gagasan bahwa torsi yang diperlukan untuk mengubah suatu objek dalam cairan adalah fungsi dari viskositas cairan yang. Mereka mengukur torsi yang dibutuhkan untuk memutar disk atau tambatannya di cairan pada kecepatan dikenal.
"Piala dan bob 'Alat ukur kekentalan bekerja dengan menentukan volume tepat dari sampel yang akan dicukur dalam sel tes, torsi yang dibutuhkan untuk mencapai kecepatan rotasi tertentu diukur dan diplot. Ada dua geometri klasik di ukur kekentalan "cangkir dan bob", yang dikenal sebagai baik "Couette" atau "Searle" sistem - dibedakan oleh apakah cangkir atau bob berputar. Cangkir berputar lebih disukai dalam beberapa kasus karena mengurangi terjadinya vortisitas Taylor, tetapi lebih sulit untuk mengukur secara akurat.
'Cone dan Plate' Alat ukur kekentalan menggunakan kerucut sudut yang sangat dangkal dalam kontak terbuka dengan pelat datar. Dengan sistem ini laju geser pelat bawah adalah konstan untuk tingkat sederhana presisi dan dekonvolusi dari suatu kurva aliran; grafik tegangan geser (torsi) terhadap laju geser (kecepatan sudut) menghasilkan viskositas secara langsung.
viskometer Stormer
Viskometer Stormer adalah instrumen rotasi yang digunakan untuk menentukan viskositas cat, biasa digunakan dalam industri cat. Ini terdiri dari sebuah rotor dayung-tipe yang berputar dengan motor internal, tenggelam ke dalam sebuah silinder zat kental. Kecepatan rotor dapat disesuaikan dengan mengubah jumlah beban disuplai ke rotor. Misalnya, dalam salah satu merek Alat ukur kekentalan, mendorong tingkat atas mengurangi beban dan kecepatan, ke bawah meningkatkan beban dan kecepatan.
Viskositas dapat ditemukan dengan menyesuaikan beban sampai kecepatan rotasi 200 rotasi per menit. Dengan memeriksa beban diterapkan dan membandingkan tabel ditemukan pada ASTM D 562, orang dapat menemukan dalam satuan viskositas Krebs (KU), unik hanya dengan viskometer Stormer jenis.
Metode ini dimaksudkan untuk cat diterapkan oleh kuas atau roller.
Gelembung viskometer
Alat ukur kekentalan gelembung digunakan untuk dengan cepat menentukan viskositas kinematik cairan dikenal seperti resin dan pernis. Waktu yang diperlukan untuk gelembung udara meningkat berbanding lurus dengan visosity cairan, sehingga lebih cepat naik gelembung, semakin rendah viskositas. Perbandingan Metode Alfabetis menggunakan 4 set tabung referensi huruf, A5 melalui z10, viskositas diketahui mencakup rentang viskositas dari 0,005 sampai 1.000 stoke. Metode Waktu Langsung menggunakan tabung 3-baris kali untuk menentukan "detik gelembung", yang kemudian dapat dikonversi menjadi stoke.
jenis viskometer Miscellaneous
Jenis viskometer lain menggunakan bola atau benda lainnya. Alat ukur kekentalan yang dapat mencirikan non-Newtonian cairan biasanya disebut rheometers atau plastometers.
Dalam viskometer ICI "Oscar", dapat disegel cairan itu terombang-ambing torsionally, dan dengan teknik pengukuran yang cerdas itu mungkin untuk mengukur viskositas dan elastisitas baik dalam sampel.
Corong Marsh viskometer mengukur viskositas dari waktu (efluks waktu) dibutuhkan volume yang diketahui cairan mengalir dari dasar kerucut melalui tabung pendek. Hal ini mirip dalam prinsip cangkir aliran (penghabisan cangkir) seperti cangkir Ford, Zahn dan Shell yang menggunakan bentuk yang berbeda untuk kerucut dan ukuran nozzle berbagai. Pengukuran dapat dilakukan sesuai dengan ISO 2431, ASTM D1200 - 10 atau DIN 53411.
Prosedur
Kalibrasi Viscometer
Akurasi dari Viscometer
Brookfield diverifikasi dengan menggunakan cairan standard yang disediakan oleh
Brookfield Engineering Labs. Cairan Standard ini merupakan cairan Newtonian
sehingga memiliki nilai viskosiats yang sama dengan pemakaian sembarang
spindle, RPM maupun shear rate. Cairan standard yang tersedia telah dikalibrasi
pada suhu 25 oC.
Persyaratan Umum :
Ukuran wadah : Untuk Viscosity
Standard < 30.000 cP, gunakanlah Beaker Low Form 600 ml. Untuk Viscosity
Standard > 30.000 cP gunakan wadah cairan sbb. : Dia. Dalam : 8.25 cm,
Tinggi : 12.1 cm. Catatan : Wadah boleh lebih besar tetapi tidak boleh lebih
kecil.
Suhu : Seperti tercantum pada
label standard ± 0.1 oC.
Kondisi : Viscometer dengan
Model : “LV” atau “RV” harus menggunakan Guarg Leg.
Brookfield merekomendasikan
untuk mengganti cairan Standard setelah 1 (satu) tahun sejak pemakaian.
Prosedur kalibrasi untuk
Spindle LV(#1-4), RV, HA, HB (#1-7).
- Letakkan cairan standard (dalam wadah yang sesuai) ke dalam Water Bath.
- Atur Viscometer pada posisi pengukuran (gunakan Guard Leg untuk Model LV dan RV).
- Pasangkan spindle pada Viscometer. Hindari terjebaknya gelembung udara dibawah spindle.
- Cairan standard bersama spindle harus dicelupkan ke dalam water bath selama minium 1 (satu) jam. Cairan diaduk sebelum pengukuran.
- Setelah 1 jam, periksa suhu cairan standard dengan themometer yang akurat.
- Jika suhu cairan telah mencapai suhu pengujian (± 0.1 oC) lakukan pengukuan viskositas dan catat hasil pembacaan viscometer. Catatan : spindle harus berputar sedikitnya 5 (lima) kali putaran sebelum dilakkan pembacaan.
- Pembacaan nilai viskositas harus sama dengan nilai cP yang tertera pada cairan standard dengan toleransi kombinasi akurasi Viscometer dan Cairan Standard. (Lihat : Interpretasi Hasil Test Kalibrasi)
Prosedur Kalibrasi untuk
Small Sample Adapter
Jika Small Sample Adapter
digunakan, water jacket dihubungkan dengan water bath dan akir dikonsisikan
pada suhu yang sesuai.
- Letakkan sejumlah sample sesuai petunjuk ke dalam sample chamber. Jumlah sample berbeda-beda untuk spnle yang berbeda. (Sesuaikan dengan Instruction Manual dari Small Sample Adapter).
- Letakkan sample chamber ke dalam water jacket.
- Pasangkan spindle
- Biarkan selama 30 menit agar cairan standard mencapai suhu test.
- Lakukan pengukuran dan catat hasilnya. Spindle harus berputar minimum 5 kali sebelum dilakukan pembacaan.
Prosedur Kalibrasi untuk
Thermosel System
Ada 2 step yang direkomendasikan
untuk mengkalibrasi Thermosel.
A. Kalibrasi Viscometer
tersendiri dengan Spindle Standard (Lihat : Prosedur kalibrasi untuk Spindle
LV(#1-4), RV, HA, HB (#1-7)).
B. Kalibrasi Viscometer dengan
Thermosel sesuai dengan prosedur berikut ini :
a. Letakkan sejumlah cairan HT
(High Temperature) viscosity standard ke dalam HT-2 sample chamber. Jumlah
sample berbeda-beda untuk tiap spindle. (Lihat : Instruksi Manual Thermosel ).
b. Letakkan sample chamber ke dalam
Thermo Container.
- Pasangkan spindle
- Biarkan selama 30 menit agar suhu setting tercapai
- Lihat dan catat hasil pengukuran. Catatan : Spindle harus berputar setidaknya 5 putaran sebelum dilakukan pembacaan.
Prosedur Kalibrasi untuk
UL atau DIN UL Adapter
- Letakkan sejumlah cairan viscosity standard ke dalam UL Tube. Lihat : Instruction Manual UL Adapter.
- Pasangkan spindle pada viscometer
- Pasangkan Tube / Wadah Sample
- Celupkan Tube ke dalam Water Bath. Jika menggunakan ULA-40Y water jacket, hubungkan saluran inlet / outlet ke external circulating pump.
- Biarkan selama 30 menit agar tercapai suhu setting
- Lakukan pengukuran viscosity dan catat hasilnya. Spindle harus berputar minimal 5 puataran sebelum dilakukan pembacaan hasilnya.
Prosedur Kalibrasi untuk
Helipath Stand dan Spindle T-Bar
Kalibrasi Helipath Stand dan
Spindle T-Bar dapat dilakuan dengan menggunakan Spinlde standard yang ada
(Lihat : Prosedur kalibrasi untuk Spindle LV(#1-4), RV, HA, HB (#1-7)). Spindle
T-Bar tidak boleh digunakan untuk verifikasi kalibrasi.
Prosedur Kalibrasi untuk
Spiral Adapter
- Letakkan viscosity standard yang ada di Beaker ke dalam water bath.
- Pasangkan spindle pada viscometer. Pasangkan chamber (SA-1Y)
- Atur viscometer pada posisi pengukuran. Operasikan viscometer pada 50 atau 60 RPM sampai chamber benar-benar meluap.
- Cairan viscosity standard bersama dengan spindle harus dibenamkan ke dalam water bath selama minimum 1 jam dan diaduk secara teratur sebelum dilakukan pengukuran.
- Setelah 1 jam, cek suhu cairan dengan menggunakan thermometer yang akurat
- Jika cairan sudah mencapai suhu setting ± 0.1 oC, ukur kekentalan cairan. Catatan : Spindle harus berputar minimal 5 kali putaran sebelum pengukuran dilakukan.
- Hasil pengukuran harus sama dengan nilai standard dengan toleransi gabungan akurasi dari viscometer dan cairan standard. ( Lihat : Interpretasi Hasil Test Kalibrasi).
Prosedur Kalibrasi untuk
Cone/Plate Viscometer
- Atur jarak antara cone spindle dengan plate sesuai dengan Instruction Manual
- Pilih viscsity standard yang akan memberikan nilai pembacaan antara 10% hingga 100% dari Full Scale Range (FSR). Sebaiknya pilih standard dengan nilai mendekati 100% FSR.
- Masukkan sample ke dalam cup dan biarkan selama 15 menit untuk mencapai suhu setting.
- Lakukan pengukuran dan catat hasilnya baik % Torque dan cP. Catatan :
- Spindle harus berputar minimum 5 putaran sebelum pengukuran diambil.
- Penggunaan standard pada rentang 5 cP s.d 5.000 cP dianjurkan untuk instrument cone/plate. Jangan gunakan viscsity standard diatas 5.000 cP.
Interpretasi Hasil Test
Kalibrasi
Pada saat melakukan verifikasi
kalibrasi Viscometer Model Spindle Brookfield, faktor kesalahan (toleransi)
dari alat dan cairan standard harus digabungkan untuk menghitung total
toleransi yang diijinkan. Toleransi dari viscometer Brookfield adalah 1% dari
Full Scale Range (FSR). FSR adalah nilai maksium yang mampu diukur oleh alat
dengan kombinasi setting Spindle dan Kecepatan putar spindle yang kita
tetapkan. Sedangkan toleransi dari cairan standard adalah 1% dari nilai
viscosity cairan yang bersangkutan.
Contoh perhitungan :
- FSR alat ukur 50.000 cP
- Cairan Standard 12.000 dengan nilai actual 12.257 pada suhu 25 oC.
- Toleransi alat adalah : 1% x 50.000 = 500 cP
- Toleransi cairan standard : 1% x 12.257 = 122.57 cP
- Total Toleransi : ± ( 500 + 122.57) = ± 622.57 cP
- Sehingga pembacaan yang diijinkan dengan FSR dan standard di atas adalah :
Toleransi yang dapat diterima =
( 12.257 ± 622.57 ) cP.
Sejauh pembacaan alat masih
dalam rentang nilai tersebut, maka viscometer masih berfungsi dengan baik.
MAGNETIC STIRRER
Sebuah pengaduk magnetik
atau mixer magnetik adalah perangkat laboratorium yang menggunakan medan magnet berputar untuk menyebabkan batang pengaduk direndam dalam cairan berputar
sangat cepat, sehingga aduk. Bidang berputar
dapat dibuat baik oleh magnet berputar atau satu
set elektromagnet stasioner,
ditempatkan di bawah kapal dengan cairan. Pengaduk magnetik sering termasuk hot plate atau beberapa cara lain untuk pemanas cairan.
Pengaduk magnetik sering digunakan dalam kimia dan biologi. Mereka lebih dipilih daripada gigi-didorong pengaduk bermotor karena mereka lebih tenang, lebih efisien, dan tidak memiliki bagian yang bergerak eksternal untuk istirahat atau aus (selain magnet batang sederhana itu sendiri). Karena ukurannya yang kecil, bar pengadukan lebih mudah dibersihkan dan disterilkan dari perangkat aduk lainnya. Mereka tidak membutuhkan pelumas yang dapat mencemari bejana reaksi dan produk. Mereka dapat digunakan di dalam pembuluh tertutup tertutup atau sistem, tanpa perlu segel rotary rumit.
Di sisi lain, ukuran terbatas bar berarti bahwa pengaduk magnetik hanya dapat digunakan untuk percobaan relatif kecil (di bawah 4 liter). Mereka juga mengalami kesulitan berurusan dengan cairan kental atau suspensi tebal.
Pengaduk magnetik sering digunakan dalam kimia dan biologi. Mereka lebih dipilih daripada gigi-didorong pengaduk bermotor karena mereka lebih tenang, lebih efisien, dan tidak memiliki bagian yang bergerak eksternal untuk istirahat atau aus (selain magnet batang sederhana itu sendiri). Karena ukurannya yang kecil, bar pengadukan lebih mudah dibersihkan dan disterilkan dari perangkat aduk lainnya. Mereka tidak membutuhkan pelumas yang dapat mencemari bejana reaksi dan produk. Mereka dapat digunakan di dalam pembuluh tertutup tertutup atau sistem, tanpa perlu segel rotary rumit.
Di sisi lain, ukuran terbatas bar berarti bahwa pengaduk magnetik hanya dapat digunakan untuk percobaan relatif kecil (di bawah 4 liter). Mereka juga mengalami kesulitan berurusan dengan cairan kental atau suspensi tebal.
ViscometerA viscometer (also called viscosimeter) is an instrument used to measure the viscosity of a fluid. For liquids with a viscosity that varies with flow conditions, an instrument called a rheometer is used. Viscometers measure only one under flow conditions.
In general, both the fluid remains stationary and moving objects through it, or a stationary object and fluid moving through it. Drag caused by the relative motion of the fluid and the surface is a measure of viscosity. Flow conditions should have a value that is small enough for it to be the Reynolds number laminar flow.
At 20.00 degrees Celsius viscosity of water is 1.002 MPa ° S and its kinematic viscosity (viscosity ratio of the density) is 1.0038 mm2 / s. These values are used to calibrate a particular type viscometer.
U tube viscometers
The device is also known as a glass capillary viscometers or Ostwald viscometers, named after Wilhelm Ostwald. Another version is a Ubbelohde viscometer, which consists of a U-shaped glass tube held vertically in a temperature controlled bath. In one arm of the U is the proper vertical narrow bore (capillary). Above this is a bulb, a bulb that is another lower in the other arm. In use, fluid is drawn into the upper ball with suction, and then allowed to flow through the capillary into a low ball. Two marks (one above and one below the ball above) shows a known volume. The time needed for the fluid to pass between the marks is proportional to the kinematic viscosity. Most of the commercial unit is provided with a conversion factor, or can be calibrated by the fluid properties are known.
The time needed for the test fluid to flow through the capillary with a known diameter of a particular factor is measured between two marked points. By passing the time taken by a factor of viscometer, the kinematic viscosity is obtained.
Viscometers are also classified as direct or reverse current flow. Reverse flow viscometers have the reservoir on top of the signs and direct flow to the reservoir bottom are those signs. Classification as there are so levels can be determined even when the fluid opaque or staining were measured, otherwise the liquid will cover signs and make it impossible to measure the rate of time passing mark. It also allows the viscometer to have more than one set of signs to allow for time directly from the time it takes to reach the 3, resulting in two timings and allow for subsequent calculations Determinability to ensure accurate results.
Piston Viscometer fallingViscometer Norcross In-Tank
Also known as Norcross viscometer because the inventor, Austin Norcross. The principle of viscosity measurement in harsh industrial and sensitive devices based on the piston and cylinder assembly. Piston periodically raised by air lift mechanism, drawing the material down through the clearance measured (gap) between the piston and cylinder wall into the space formed below the piston as it is raised. The assembly is then typically held for several seconds, then allowed to fall by gravity, expelling the sample out through the same path that goes, creating the effect of shear on the fluid is measured, which makes the viscometer is very sensitive and kind to measure the specific fluid thixotropic. Fall time is a measure of viscosity, the distance between the piston and cylinder in the form measurements of the hole. Viscosity controller measures the time of fall (Time-of-fall seconds to measure the viscosity) and displays the resulting value of viscosity. Controller can calibrate the time-of-falling value of second cup (known efflux cup), SSU or centipoise.Industrial use is very popular because of its simplicity, repeatability maintenance, low and long life. This type of measurement is not affected by the rate of flow or external vibrations. The operating principle can be adopted for different conditions, making it ideal for process control environment.
Oscillating Piston Viscometer
Sometimes referred to as electromagnetic or EMV Viscometer viscometer, the viscosity of Cambridge was created in 1986. Sensor (see figure below) consists of the measurement chamber and piston magnetically influenced. Measurements taken where samples were first introduced into the measurement chamber in which controlled thermal piston located. Electronic drive oscillating motion of the piston into the measurement chamber with a controlled magnetic field. A shear stress imposed on the fluid (or gas) as it travels the piston and the viscosity is determined by measuring the travel time of the piston. Construction parameters for the distance between the piston and the annular space measurements, the electromagnetic field strength, and the piston travel distance is used to calculate the viscosity of Newtonian viscosity according to Law.See Scheme oscillating piston Viscometer
Oscillating Piston Viscometer technology has been adapted to the viscosity of small samples and testing samples of micro-viscosity in laboratory applications. It has also been adapted to measure the viscosity measurements of high pressure and high temperature viscosity in both laboratory and process environments. Viscosity sensor has been improved for a wide range of industrial applications such as small size viscometers for use in compressor and engine, the flow-through viscometers for the dip coating process, in-line viscometers for use in refineries, and hundreds of other applications. Improvements in the sensitivity of modern electronics, stimulate the growth of popularity Oscillating Piston Viscometer with academic laboratories to explore the gas viscosity.
Vibration viscometers
Vibration viscometers Bendix instrument dates back to 1950, which is a class that operates by measuring the damping of electromechanical oscillations of the resonator is immersed in the fluid viscosity to be determined. Resonator generally oscillates in torsion or transverse (as a cantilever beam or tuning fork). The higher the viscosity, the greater the damping imposed on the resonator. Resonator damping which can be measured by any of several methods:
Measuring the input power required to maintain the oscillator to vibrate at a constant amplitude. The higher viscosity, more power is needed to maintain the oscillation amplitude.
Measuring the oscillation decay time after excitation is turned off. The higher the viscosity, the faster the signal decays.
Measure the frequency of the resonator as a function of the phase angle between excitation and response waveforms. The higher the viscosity, the greater the change in frequency for the phase change is given.
Vibration instruments also suffer from a lack of defined shear field, which makes it suitable for measuring the viscosity of the fluid flow behavior is not known before hand.
Vibrating viscometers are rugged industrial systems used to measure the viscosity of the process conditions. Active part of the sensor is a vibrating rod. Vibration amplitude varies according to the viscosity of the fluid in which the stem is submerged. This meter is suitable for measuring the viscosity of the fluid clogging and high viscosity fluids, including those with fiber (up to 1,000 Pa ° S). Today, many industries around the world consider these viscometers to be the most efficient system that can be used to measure the viscosity of various liquids on the contrary, rotational viscometers require more maintenance, are not able to measure the fluid blockage, and require frequent calibration after intensive use. Vibrating viscometers have no moving parts, no part of the weak and the sensitivity is very small. Even a very basic fluid or acid can be measured by adding a protective coating or by changing the sensor material for materials such as 316L, SUS316, or email
Rotation viscometers
Rotational viscometers use the idea that the torque required to turn an object in a fluid is a function of fluid viscosity. They measure the torque required to rotate the disk or bob in the fluid at known speed.
"Cup and bob 'viscometers work by determining the exact volume of sample to be sheared in a test cell, the torque required to achieve a certain rotational speed is measured and plotted. There are two classical geometry in viscometers" cup and bob ", which is known as both "Couette" or "Searle" systems - distinguished by whether the cup or bob rotates. cups spin in some cases preferred because it reduces the occurrence of Taylor vortices, but it is more difficult to measure accurately.
'Cone and Plate' viscometers use a cone angle is very shallow in open contact with the flat plate. With this system the lower plate shear rate is constant for a modest level of precision and deconvolution of the flow curve; graphs of shear stress (torque) against shear rate (angular velocity) produces viscosity directly.Stormer viscometer
Stormer rotational viscometer is an instrument used to determine the viscosity of paint, commonly used in paint industry. It consists of a paddle-type rotor that spins with internal motor, submerged into a cylindrical viscous substance. Rotor speed can be adjusted by changing the amount of load supplied to the rotor. For example, in one brand of viscometers, pushing the level up to reduce load and speed, under increasing load and speed.
Viscosity can be found by adjusting the load until the rotation speed of 200 rotations per minute. By examining and comparing the applied load tables found on ASTM D 562, the viscosity can be found in Krebs units (KU), unique only to the Stormer type viscometer.This method is intended to be applied by brush or paint roller.
Bubble viscometer
Bubble viscometers are used to quickly determine the kinematic viscosity of fluid known as resin and varnish. The time required for air bubbles rising visosity directly proportional to the fluid, resulting in faster rising bubbles, the lower the viscosity.Alphabetical Comparison Method using four sets of tubes reference letter, A5 through z10, cover the range of known viscosity viscosity of 0.005 to 1,000 stokes. When using the tube method Direct 3-line time to determine the "second bubble", which can then be converted to stoke.
type viscometer Miscellaneous
Another type of viscometer using a ball or other object. Viscometers which can characterize non-Newtonian fluids are usually called rheometers or plastometers.
In the viscometer ICI "Oscar", can be sealed fluid to oscillate torsionally, and with a clever measurement techniques it is possible to measure both viscosity and elasticity in the sample.
Marsh funnel viscometer measures the viscosity of the time (efflux time) it takes a known volume of fluid flowing from the base of the cone through a short tube. It is similar in principle to the flow cup (cup final) such as cups Ford, Zahn and Shell are using different forms for different cone and nozzle size. Measurements can be performed in accordance with ISO 2431, ASTM D1200 - 10 or DIN 53 411.
Calibration procedures VISCOMETER
Accuracy of Brookfield VISCOMETER verified using standard fluid provided by Brookfield Engineering Labs. Standard liquid is a Newtonian fluid that has the same value viskosiats use any spindle, RPM and shear rate. Available standard liquid has been calibrated at a temperature of 25 oC.General Requirements:Container size: For Viscosity Standards <30,000 cP, use Beaker Low Form 600 ml.Viscosity Standard for> 30 000 cP using a liquid container as follows. : He. In: 8:25 cm, Height: 12.1 cm. Note: The container may be larger but not smaller.Temperature: As listed on the label ± 0.1 ° C standard.Conditions: VISCOMETER with Model: "LV" or "RV" must use Guarg Leg.Brookfield Standard recommends to replace fluids after 1 (one) year from the usage.Spindle calibration procedure for LV (# 1-4), RV, HA, HB (# 1-7).Put a standard fluid (in a suitable container) into a Water Bath.Set VISCOMETER the measurement position (use the Leg Guard for Model LV and RV).Fit the spindle on VISCOMETER. Avoid air bubbles trapped under the spindle.Standard liquids with spindle must be dipped in a water bath for a minium of 1 (one) hour. Liquid stirred prior to measurement.After 1 hour, check the temperature of the liquid standard with themometer accurate.If the temperature of the liquid has reached the testing temperature (± 0.1 ° C) did pengukuan viscosity and record the viscometer reading. Note: The spindle must rotate at least 5 (five) rounds before dilakkan readings.The reading of the viscosity should be equal to the value indicated on the liquid cP standard with a combination of tolerance and accuracy VISCOMETER Standard Fluids.(See: Interpretation of Calibration Test Results)Calibration Procedure for Small Sample AdapterIf the Small Sample Adapter is used, a water jacket connected with a water bath and akir dikonsisikan at the appropriate temperature.Put the number of samples as per the instructions in the sample chamber. Number of different samples for different spnle. (Adjust with the Instruction Manual of Small Sample Adapter).Place the sample chamber into the water jacket.Fit the spindleLet stand for 30 minutes in order to achieve a standard liquid test temperature.Perform measurements and record the result. Spindle must rotate at least 5 times before reading.Calibration procedures for Thermosel SystemThere are two steps are recommended to calibrate Thermosel.A. VISCOMETER own calibration with Standard Spindle (See: Calibration Procedure for LV Spindle (# 1-4), RV, HA, HB (# 1-7)).B. Thermosel VISCOMETER calibration with in accordance with the following procedure:a. Put some liquid HT (High Temperature) viscosity standards in the HT-2 sample chamber. Number of different samples for each spindle. (See: Instruction Manual Thermosel).b. Place the sample chamber into the Thermo Container.Fit the spindleLet stand for 30 minutes so the temperature setting is reachedView and record the measurement results. Note: The spindle must rotate at least five rounds before the reading.Calibration Procedure for UL or DIN UL AdapterPut a number of standard viscosity fluid into the UL Tube. View: UL Adapter Instruction Manual.Attach the spindle to the viscometerPair Tube / Sample ContainersDip into Water Bath Tube. If using the ULA-40Y water jacket, connect the inlet / outlet to the external circulating pump.Let stand for 30 minutes to reach the temperature settingPerform measurements of viscosity and record the result. Spindle must rotate at least 5 puataran prior to reading the results.Calibration procedures for Helipath Stand and T-Bar SpindleCalibration Spindle Helipath Stand and T-Bar can Spinlde was done by using the existing standard (See: Calibration Procedure for LV Spindle (# 1-4), RV, HA, HB (# 1-7)). T-Bar spindles should not be used for calibration verification.Calibration Procedure for Spiral AdapterPlace the viscosity standard in Beaker into the water bath.Fit the spindle on the viscometer. Fit the chamber (SA-1Y)Adjust the position measurement viscometer. Operate the viscometer at 50 or 60 RPM until the chamber is really overwhelming.Standard viscosity liquids together with the spindle must be immersed into a water bath for a minimum of 1 hour and stirred on a regular basis prior to measurement.After 1 hour, check the temperature of the fluid by using an accurate thermometerIf the liquid has reached the set temperature ± 0.1 ° C, measuring the fluid viscosity.Note: The spindle must rotate at least five times round before measurements were made.The results of measurements should be equal to the standard of accuracy combined with a tolerance of viscometer and standard liquids. (See: Interpretation of Calibration Test Results).Calibration Procedure for Cone / Plate VISCOMETERAdjust the distance between the spindle cone plate in accordance with the Instruction ManualSelect viscsity standard that will give a reading between 10% to 100% of Full Scale Range (FSR). Should select a standard with a value close to 100% FSR.Insert the sample into the cup and let stand for 15 minutes to reach the temperature setting.Perform measurements and record the result both% torque and cP. Note:Spindle must rotate a minimum of 5 laps before the measurement is taken.The use of standards in the range of 5 cP up to 5000 cP instrument is recommended for cone / plate. Do not use standard viscsity above 5000 cP.Interpretation of Calibration Test ResultsAt the time of calibration verification VISCOMETER Brookfield Spindle model, the error factor (tolerance) of standard tools and fluids must be combined to calculate the total allowable tolerance. Tolerance of the Brookfield viscometer is 1% of Full Scale Range (FSR). FSR is of maximum value that can be measured by means of a combination of setting Spindle and spindle rotary speed that we set. While the tolerance of the standard liquid is 1% of the value of fluid viscosity is concerned.Example calculation:FSR gauge 50 000 cPStandard fluids 12 257 12 000 with the actual value at a temperature of 25 oC.Tolerance means is: 1% x 50,000 = 500 cPTolerance standard liquid: 1% x 12 257 = 122.57 cPTotal Tolerance: ± (500 + 122.57) = 622.57 ± cPSo that the readings are allowed by FSR and above the standard are:Acceptable tolerance = (12 257 ± 622.57) cP.As far as the reading of the instrument is still within the range of values, then the viscometer is still functioning properly.
MAGNETIC StirrerA magnetic stirrer or magnetic mixer are laboratory devices that use rotating magnetic field to cause a stir bar immersed in a fluid rotating very quickly, so stir. Rotating field can be made either by a rotating magnet or a set of stationary electromagnets, placed at the bottom of the vessel with liquid. Often include a magnetic stirrer hot plate or some other means for heating the liquid.
Magnetic stirrer is often used in chemistry and biology. They are preferred over gear-driven stirrer motor because they are quieter, more efficient, and has no external moving parts to break or wear out (other than a simple bar magnet itself). Because of its small size, the stirring bar is more easily cleaned and sterilized than other stirring device. They do not require lubricants that can contaminate the reaction vessel and products. They can be used in a closed vessel or a closed system, without the need for complex rotary seals.
On the other hand, the limited size means that the magnetic stirrer bar can only be used for the experiment is relatively small (under 4 liters). They also have difficulty dealing with a thick viscous liquid or suspension.
In general, both the fluid remains stationary and moving objects through it, or a stationary object and fluid moving through it. Drag caused by the relative motion of the fluid and the surface is a measure of viscosity. Flow conditions should have a value that is small enough for it to be the Reynolds number laminar flow.
At 20.00 degrees Celsius viscosity of water is 1.002 MPa ° S and its kinematic viscosity (viscosity ratio of the density) is 1.0038 mm2 / s. These values are used to calibrate a particular type viscometer.
U tube viscometers
The device is also known as a glass capillary viscometers or Ostwald viscometers, named after Wilhelm Ostwald. Another version is a Ubbelohde viscometer, which consists of a U-shaped glass tube held vertically in a temperature controlled bath. In one arm of the U is the proper vertical narrow bore (capillary). Above this is a bulb, a bulb that is another lower in the other arm. In use, fluid is drawn into the upper ball with suction, and then allowed to flow through the capillary into a low ball. Two marks (one above and one below the ball above) shows a known volume. The time needed for the fluid to pass between the marks is proportional to the kinematic viscosity. Most of the commercial unit is provided with a conversion factor, or can be calibrated by the fluid properties are known.
The time needed for the test fluid to flow through the capillary with a known diameter of a particular factor is measured between two marked points. By passing the time taken by a factor of viscometer, the kinematic viscosity is obtained.
Viscometers are also classified as direct or reverse current flow. Reverse flow viscometers have the reservoir on top of the signs and direct flow to the reservoir bottom are those signs. Classification as there are so levels can be determined even when the fluid opaque or staining were measured, otherwise the liquid will cover signs and make it impossible to measure the rate of time passing mark. It also allows the viscometer to have more than one set of signs to allow for time directly from the time it takes to reach the 3, resulting in two timings and allow for subsequent calculations Determinability to ensure accurate results.
Piston Viscometer fallingViscometer Norcross In-Tank
Also known as Norcross viscometer because the inventor, Austin Norcross. The principle of viscosity measurement in harsh industrial and sensitive devices based on the piston and cylinder assembly. Piston periodically raised by air lift mechanism, drawing the material down through the clearance measured (gap) between the piston and cylinder wall into the space formed below the piston as it is raised. The assembly is then typically held for several seconds, then allowed to fall by gravity, expelling the sample out through the same path that goes, creating the effect of shear on the fluid is measured, which makes the viscometer is very sensitive and kind to measure the specific fluid thixotropic. Fall time is a measure of viscosity, the distance between the piston and cylinder in the form measurements of the hole. Viscosity controller measures the time of fall (Time-of-fall seconds to measure the viscosity) and displays the resulting value of viscosity. Controller can calibrate the time-of-falling value of second cup (known efflux cup), SSU or centipoise.Industrial use is very popular because of its simplicity, repeatability maintenance, low and long life. This type of measurement is not affected by the rate of flow or external vibrations. The operating principle can be adopted for different conditions, making it ideal for process control environment.
Oscillating Piston Viscometer
Sometimes referred to as electromagnetic or EMV Viscometer viscometer, the viscosity of Cambridge was created in 1986. Sensor (see figure below) consists of the measurement chamber and piston magnetically influenced. Measurements taken where samples were first introduced into the measurement chamber in which controlled thermal piston located. Electronic drive oscillating motion of the piston into the measurement chamber with a controlled magnetic field. A shear stress imposed on the fluid (or gas) as it travels the piston and the viscosity is determined by measuring the travel time of the piston. Construction parameters for the distance between the piston and the annular space measurements, the electromagnetic field strength, and the piston travel distance is used to calculate the viscosity of Newtonian viscosity according to Law.See Scheme oscillating piston Viscometer
Oscillating Piston Viscometer technology has been adapted to the viscosity of small samples and testing samples of micro-viscosity in laboratory applications. It has also been adapted to measure the viscosity measurements of high pressure and high temperature viscosity in both laboratory and process environments. Viscosity sensor has been improved for a wide range of industrial applications such as small size viscometers for use in compressor and engine, the flow-through viscometers for the dip coating process, in-line viscometers for use in refineries, and hundreds of other applications. Improvements in the sensitivity of modern electronics, stimulate the growth of popularity Oscillating Piston Viscometer with academic laboratories to explore the gas viscosity.
Vibration viscometers
Vibration viscometers Bendix instrument dates back to 1950, which is a class that operates by measuring the damping of electromechanical oscillations of the resonator is immersed in the fluid viscosity to be determined. Resonator generally oscillates in torsion or transverse (as a cantilever beam or tuning fork). The higher the viscosity, the greater the damping imposed on the resonator. Resonator damping which can be measured by any of several methods:
Measuring the input power required to maintain the oscillator to vibrate at a constant amplitude. The higher viscosity, more power is needed to maintain the oscillation amplitude.
Measuring the oscillation decay time after excitation is turned off. The higher the viscosity, the faster the signal decays.
Measure the frequency of the resonator as a function of the phase angle between excitation and response waveforms. The higher the viscosity, the greater the change in frequency for the phase change is given.
Vibration instruments also suffer from a lack of defined shear field, which makes it suitable for measuring the viscosity of the fluid flow behavior is not known before hand.
Vibrating viscometers are rugged industrial systems used to measure the viscosity of the process conditions. Active part of the sensor is a vibrating rod. Vibration amplitude varies according to the viscosity of the fluid in which the stem is submerged. This meter is suitable for measuring the viscosity of the fluid clogging and high viscosity fluids, including those with fiber (up to 1,000 Pa ° S). Today, many industries around the world consider these viscometers to be the most efficient system that can be used to measure the viscosity of various liquids on the contrary, rotational viscometers require more maintenance, are not able to measure the fluid blockage, and require frequent calibration after intensive use. Vibrating viscometers have no moving parts, no part of the weak and the sensitivity is very small. Even a very basic fluid or acid can be measured by adding a protective coating or by changing the sensor material for materials such as 316L, SUS316, or email
Rotation viscometers
Rotational viscometers use the idea that the torque required to turn an object in a fluid is a function of fluid viscosity. They measure the torque required to rotate the disk or bob in the fluid at known speed.
"Cup and bob 'viscometers work by determining the exact volume of sample to be sheared in a test cell, the torque required to achieve a certain rotational speed is measured and plotted. There are two classical geometry in viscometers" cup and bob ", which is known as both "Couette" or "Searle" systems - distinguished by whether the cup or bob rotates. cups spin in some cases preferred because it reduces the occurrence of Taylor vortices, but it is more difficult to measure accurately.
'Cone and Plate' viscometers use a cone angle is very shallow in open contact with the flat plate. With this system the lower plate shear rate is constant for a modest level of precision and deconvolution of the flow curve; graphs of shear stress (torque) against shear rate (angular velocity) produces viscosity directly.Stormer viscometer
Stormer rotational viscometer is an instrument used to determine the viscosity of paint, commonly used in paint industry. It consists of a paddle-type rotor that spins with internal motor, submerged into a cylindrical viscous substance. Rotor speed can be adjusted by changing the amount of load supplied to the rotor. For example, in one brand of viscometers, pushing the level up to reduce load and speed, under increasing load and speed.
Viscosity can be found by adjusting the load until the rotation speed of 200 rotations per minute. By examining and comparing the applied load tables found on ASTM D 562, the viscosity can be found in Krebs units (KU), unique only to the Stormer type viscometer.This method is intended to be applied by brush or paint roller.
Bubble viscometer
Bubble viscometers are used to quickly determine the kinematic viscosity of fluid known as resin and varnish. The time required for air bubbles rising visosity directly proportional to the fluid, resulting in faster rising bubbles, the lower the viscosity.Alphabetical Comparison Method using four sets of tubes reference letter, A5 through z10, cover the range of known viscosity viscosity of 0.005 to 1,000 stokes. When using the tube method Direct 3-line time to determine the "second bubble", which can then be converted to stoke.
type viscometer Miscellaneous
Another type of viscometer using a ball or other object. Viscometers which can characterize non-Newtonian fluids are usually called rheometers or plastometers.
In the viscometer ICI "Oscar", can be sealed fluid to oscillate torsionally, and with a clever measurement techniques it is possible to measure both viscosity and elasticity in the sample.
Marsh funnel viscometer measures the viscosity of the time (efflux time) it takes a known volume of fluid flowing from the base of the cone through a short tube. It is similar in principle to the flow cup (cup final) such as cups Ford, Zahn and Shell are using different forms for different cone and nozzle size. Measurements can be performed in accordance with ISO 2431, ASTM D1200 - 10 or DIN 53 411.
Calibration procedures VISCOMETER
Accuracy of Brookfield VISCOMETER verified using standard fluid provided by Brookfield Engineering Labs. Standard liquid is a Newtonian fluid that has the same value viskosiats use any spindle, RPM and shear rate. Available standard liquid has been calibrated at a temperature of 25 oC.General Requirements:Container size: For Viscosity Standards <30,000 cP, use Beaker Low Form 600 ml.Viscosity Standard for> 30 000 cP using a liquid container as follows. : He. In: 8:25 cm, Height: 12.1 cm. Note: The container may be larger but not smaller.Temperature: As listed on the label ± 0.1 ° C standard.Conditions: VISCOMETER with Model: "LV" or "RV" must use Guarg Leg.Brookfield Standard recommends to replace fluids after 1 (one) year from the usage.Spindle calibration procedure for LV (# 1-4), RV, HA, HB (# 1-7).Put a standard fluid (in a suitable container) into a Water Bath.Set VISCOMETER the measurement position (use the Leg Guard for Model LV and RV).Fit the spindle on VISCOMETER. Avoid air bubbles trapped under the spindle.Standard liquids with spindle must be dipped in a water bath for a minium of 1 (one) hour. Liquid stirred prior to measurement.After 1 hour, check the temperature of the liquid standard with themometer accurate.If the temperature of the liquid has reached the testing temperature (± 0.1 ° C) did pengukuan viscosity and record the viscometer reading. Note: The spindle must rotate at least 5 (five) rounds before dilakkan readings.The reading of the viscosity should be equal to the value indicated on the liquid cP standard with a combination of tolerance and accuracy VISCOMETER Standard Fluids.(See: Interpretation of Calibration Test Results)Calibration Procedure for Small Sample AdapterIf the Small Sample Adapter is used, a water jacket connected with a water bath and akir dikonsisikan at the appropriate temperature.Put the number of samples as per the instructions in the sample chamber. Number of different samples for different spnle. (Adjust with the Instruction Manual of Small Sample Adapter).Place the sample chamber into the water jacket.Fit the spindleLet stand for 30 minutes in order to achieve a standard liquid test temperature.Perform measurements and record the result. Spindle must rotate at least 5 times before reading.Calibration procedures for Thermosel SystemThere are two steps are recommended to calibrate Thermosel.A. VISCOMETER own calibration with Standard Spindle (See: Calibration Procedure for LV Spindle (# 1-4), RV, HA, HB (# 1-7)).B. Thermosel VISCOMETER calibration with in accordance with the following procedure:a. Put some liquid HT (High Temperature) viscosity standards in the HT-2 sample chamber. Number of different samples for each spindle. (See: Instruction Manual Thermosel).b. Place the sample chamber into the Thermo Container.Fit the spindleLet stand for 30 minutes so the temperature setting is reachedView and record the measurement results. Note: The spindle must rotate at least five rounds before the reading.Calibration Procedure for UL or DIN UL AdapterPut a number of standard viscosity fluid into the UL Tube. View: UL Adapter Instruction Manual.Attach the spindle to the viscometerPair Tube / Sample ContainersDip into Water Bath Tube. If using the ULA-40Y water jacket, connect the inlet / outlet to the external circulating pump.Let stand for 30 minutes to reach the temperature settingPerform measurements of viscosity and record the result. Spindle must rotate at least 5 puataran prior to reading the results.Calibration procedures for Helipath Stand and T-Bar SpindleCalibration Spindle Helipath Stand and T-Bar can Spinlde was done by using the existing standard (See: Calibration Procedure for LV Spindle (# 1-4), RV, HA, HB (# 1-7)). T-Bar spindles should not be used for calibration verification.Calibration Procedure for Spiral AdapterPlace the viscosity standard in Beaker into the water bath.Fit the spindle on the viscometer. Fit the chamber (SA-1Y)Adjust the position measurement viscometer. Operate the viscometer at 50 or 60 RPM until the chamber is really overwhelming.Standard viscosity liquids together with the spindle must be immersed into a water bath for a minimum of 1 hour and stirred on a regular basis prior to measurement.After 1 hour, check the temperature of the fluid by using an accurate thermometerIf the liquid has reached the set temperature ± 0.1 ° C, measuring the fluid viscosity.Note: The spindle must rotate at least five times round before measurements were made.The results of measurements should be equal to the standard of accuracy combined with a tolerance of viscometer and standard liquids. (See: Interpretation of Calibration Test Results).Calibration Procedure for Cone / Plate VISCOMETERAdjust the distance between the spindle cone plate in accordance with the Instruction ManualSelect viscsity standard that will give a reading between 10% to 100% of Full Scale Range (FSR). Should select a standard with a value close to 100% FSR.Insert the sample into the cup and let stand for 15 minutes to reach the temperature setting.Perform measurements and record the result both% torque and cP. Note:Spindle must rotate a minimum of 5 laps before the measurement is taken.The use of standards in the range of 5 cP up to 5000 cP instrument is recommended for cone / plate. Do not use standard viscsity above 5000 cP.Interpretation of Calibration Test ResultsAt the time of calibration verification VISCOMETER Brookfield Spindle model, the error factor (tolerance) of standard tools and fluids must be combined to calculate the total allowable tolerance. Tolerance of the Brookfield viscometer is 1% of Full Scale Range (FSR). FSR is of maximum value that can be measured by means of a combination of setting Spindle and spindle rotary speed that we set. While the tolerance of the standard liquid is 1% of the value of fluid viscosity is concerned.Example calculation:FSR gauge 50 000 cPStandard fluids 12 257 12 000 with the actual value at a temperature of 25 oC.Tolerance means is: 1% x 50,000 = 500 cPTolerance standard liquid: 1% x 12 257 = 122.57 cPTotal Tolerance: ± (500 + 122.57) = 622.57 ± cPSo that the readings are allowed by FSR and above the standard are:Acceptable tolerance = (12 257 ± 622.57) cP.As far as the reading of the instrument is still within the range of values, then the viscometer is still functioning properly.
MAGNETIC StirrerA magnetic stirrer or magnetic mixer are laboratory devices that use rotating magnetic field to cause a stir bar immersed in a fluid rotating very quickly, so stir. Rotating field can be made either by a rotating magnet or a set of stationary electromagnets, placed at the bottom of the vessel with liquid. Often include a magnetic stirrer hot plate or some other means for heating the liquid.
Magnetic stirrer is often used in chemistry and biology. They are preferred over gear-driven stirrer motor because they are quieter, more efficient, and has no external moving parts to break or wear out (other than a simple bar magnet itself). Because of its small size, the stirring bar is more easily cleaned and sterilized than other stirring device. They do not require lubricants that can contaminate the reaction vessel and products. They can be used in a closed vessel or a closed system, without the need for complex rotary seals.
On the other hand, the limited size means that the magnetic stirrer bar can only be used for the experiment is relatively small (under 4 liters). They also have difficulty dealing with a thick viscous liquid or suspension.
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