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How Temperature Affects Viscosity

  How Temperature Affects Viscosity: Viscosity can be defined as the internal friction that occurs as a material flow, relative to itself....

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显示标签为“viscosity index”的博文。显示所有博文

2017年11月22日星期三

Using Ubbelohde viscometer to measure the molecular weight of polyacrylamide

Test Method: Use 85g / L sodium nitrate solution will be configured as a dilute solution sample, with Ubbelohde viscometer to determine the ultimate viscosity, according to empirical formula to calculate the molecular weight of the sample.

Reagent solution: 85g / L sodium nitrate solution
Equipment: Ubbelohde viscometer (capillary diameter 0.55mm)
Constant temperature water bath (can control 30 ℃ ± 0.1 ℃)
Stopwatch (division 0.1s)
Acid filtration funnel
The company is located in:
Experimental steps:
1. Determination of sodium nitrate solution outflow time
The clean, dry Ubbelohde viscometer vertically placed 30 ℃ ± 0.1 ℃ constant temperature water bath so that the U-viscometer D ball all submerged under the water.
Will be filtered through acid filtration funnel sodium nitrate solution was added to the Ubbelohde viscometer filling line between G, so far, constant temperature 10min-15min.
M tube set a hose, with the clip, use the ear ball to the sodium nitrate solution into the D ball half, remove the ear wash ball, open the M tube.
Measure the time it takes for the sodium nitrate solution to flow through the timed markers E, F with a stop watch. Repeated determination of three times, the error does not exceed 0.2s, whichever is the average t0.
2. Preparation of sample solution
Weigh 0.03 g of solid sample or equivalent amount of colloidal sample from a known 50 mL dry beaker to the nearest 0.2 mg and dissolve with sodium nitrate solution. All transferred to 100mL volumetric flask, diluted with sodium nitrate solution to the mark, shake.
3. Determine the outflow time of the sample solution
The outflow time t1 of the sample solution is determined by the first step method
4. Calculate the result according to the formula


Kent Yuan (Mr.)
Hangzhou Zhongwang Technology Co., LTD.
Skype: kenyuan9023   Wechat/WhatsApp:+86 15068109723lei@zonwon.com  www.zonwontech.com
    

2017年9月12日星期二

How does the viscosity index of the lubricating oil be calculated?

How does the viscosity index of the lubricating oil be calculated?
Abstract: The viscosity index indicates the degree to which all fluid viscosity varies with temperature. The higher the viscosity index, the smaller the effect of fluid viscosity on the temperature, the less sensitive the viscosity to the temperature.

IVS400 Viscometer
According to the different viscosity index, the lubricating oil can be divided into three grades: 35-80 for the medium viscosity index lubricants; 80-110 for the high viscosity index lubricants; 110 above the special high viscosity index lubricants. Viscosity index of 100-170 in the oil, high-grade multi-grade lubricants, it has a viscosity curve changes smooth and good viscosity temperature. At lower temperatures, the polymer molecules in these viscosity index improvers have little solubility in the oil and the molecules are curled into small clusters, so that the viscosity of the oil increases little; and at high temperatures it is in the oil The viscosity increases, and the curly-like linear molecules expand and elongate, so that the viscosity increases greatly, making up the viscosity of the base oil due to the temperature rise. So the higher the viscosity index, the smaller the viscosity changes with temperature.

Calculation of Viscosity Index
Viscosity index should be calculated using the formula, the viscosity index of less than 100 and higher than 100 are uses different formula. ASTM D2270 method is divided into two parts, one for the A method, another one for the B method. A method is actually ASTM D567 old method, the use of calculation method to determine the viscosity index. The B rule is intended for use with fuels with a viscosity index greater than 100.

Viscosity index (Viscosity index) formula A:
Viscosity index between 0 to 100 between the use of this formula. The formula is: viscosity index
VI = [(L-U) / (L-H)] * 100
H = viscosity of 100 known oil at 100 ° F (or 40 ° C), but its viscosity at 210 ° F should be the same as the viscosity of the unknown oil at 210 ° F (or 100 ° C). Because of its high viscosity index, so the H (High) alphabet.
L = viscosity of the known oil at 100 ° F (or 40 ° C). But its viscosity at 210 ° F (or 100 ° C) should be the same as the viscosity of the unknown oil at 210 ° F (or 100 ° C). Because of its low viscosity index, so the L (Low) alphabet.

U = unknown viscosity index of the raw material at 100 ° F (or 40 ° C).
Viscosity index (Viscosity index) algorithm B:
Specially used to calculate the viscosity index of more than 100 for the use of oil.



IVS800 Viscometer

If a result of an oil calculated by the old method is more than 100, it must be recalculated in this way and calculated as a result of the B method. And expressed as VI (E), VI (Extended), VIe, or "epitaxial viscosity index". The formula is as follows:
(N) = [(Antilog N) -1 / 0.0075] 100 where N = the viscosity of the oil sample at 210 ° F, which is equal to the desired index at the ratio of H and U at 100 ° F. which is
N = (㏒H-㏒U) / (㏒KV210), or
KV210N = H / U
KV210 = kinetic viscosity of oil sample at 210 ° F (or 100 ° C) (KV is abbreviation for Kinemetic Viscosity)
H = A known oil having a viscosity index of 100 is obtained by the A method, its kinematic viscosity at 100 ° F (or 40 ° C) (which can be determined by the 24th table)
U = the kinematic viscosity of the oil sample at 100 ° F (or 40 ° C) (where H> U)

Hangzhou Zhongwang Technology Co.,ltd provides IVS400 and IVS800 series viscometer.
It can tests the viscosity index easily.

Kent Yuan (Mr.)
Hangzhou Zhongwang Technology Co., LTD.
 /Wahtsapp: +86 15068109723  lei@zonwon.com