CS242524B1

CS242524B1 - Cup for viscosity measuring

Info

Publication number: CS242524B1
Application number: CS845919A
Authority: CS
Inventors: Stefan Janosik; Pavel Nater
Original assignee: Stefan Janosik; Pavel Nater
Priority date: 1984-08-03
Filing date: 1984-08-03
Publication date: 1986-05-15
Also published as: CS591984A1

Abstract

Riešenie sa týká nádobky na meranie viskozity pri nízkých teplotách. Podía riešenia je meracia nádobka usporiadaná tak, že z boku meracej nádobky je vyvedená trubica, ktorá umožňuje umiestnenie teploměru priamo do vzorky a zároveň slúži ako zavzdušňovacia trubica. Meracia kapilára je umiestnená koncentricky. Nádobka može byť v odbore ropy a ropných produktov a tiež všade tam, kde ,sa meria viskozita pri nízkých teplotách.The solution relates to a viscosity measuring container at low temperatures. According to the solution the measuring cup is arranged so that z the side of the measuring cup is the tube, that allows the thermometer to be positioned directly into the sample while serving as aeration tube. The measuring capillary is placed concentrically. The container may be in the oil and petroleum industry products, and wherever they are measures low temperature viscosity.

Description

Predmetom vynálezu je nádobka na meranie viskozity pri nízkých teplotách.The present invention provides a container for measuring low temperature viscosity.

Jedna z najdůležitejších charakteristik oleja je viskozita. Všeobecne sa na meranie viskozity používajú kapilárně viskozimetre, gutůčkové viskozimetre alebo rotačně viskozimetre.One of the most important characteristics of the oil is viscosity. In general, capillary viscometers, gutter viscometers or rotary viscometers are used to measure viscosity.

Medzinárodne uznávaná viskozitná klasifikácia olejov SAE J 300 SEP 80 zahřňa meranie viskozity pri 100 °C a za podmienok malého šmykového spádu, meranie viskozity pri nízkých teplotách v rozsahu —5 °C až —30 °C za podmienok vysokého šmykového spádu, 105 až 10⁶ s^-1 a meranie viskozity za podmienok malého šmykového spádu 0 až 10³ s^-1 v rozmedzí teplot —5 °C až —35 °C.The internationally recognized viscosity classification of SAE J 300 SEP 80 includes viscosity measurements at 100 ° C under low shear conditions, low temperature viscosity measurements in the range of -5 ° C to -30 ° C under high shear conditions, 105 to 10 ⁶ s ^-1 and viscosity measurement under low shear gradient conditions of 0 to 10 ³ s ^-1 in the temperature range of -5 ° C to -35 ° C.

Kým meranie viskozity pri 100 °C a meranie za podmienok vysokého šmykového spádu vcelku nerobí problémy, meranie viskozity pri nízkých teplotách a malom šmykovom spáde prináša rad problémov.While measuring viscosity at 100 ° C and measuring under high shear gradient conditions generally do not cause problems, measuring low viscosity and low shear slope presents a number of problems.

Na meranie viskozity za podmienok nízkého šmykového spádu a pri teplotách pod 0 °C sa zvyčajne používajú rotačně viskozimetre. Tieto přístroje sú dosť komplikované a drahé a zvyčajne vyžadujú použitie kalibračných kvapalín. Preto je snaha merať viskozitu pri nízkých teplotách a malých šmykových spádoch pomocou jednoduchších kapilárnych viskozimetrov, kde možno viskozitu vypočítat z rozmerov kapiláry a z nameraných veličin priamo, napr. použitím Poisseullovho vztahu.Rotary viscometers are typically used to measure viscosity under low shear gradient conditions and below 0 ° C. These instruments are quite complicated and expensive and usually require the use of calibration fluids. It is therefore an attempt to measure viscosity at low temperatures and small shear slips by means of simpler capillary viscometers, where the viscosity can be calculated directly from the dimensions of the capillary and from the measured quantities, e.g. using the Poisseull relationship.

Aparatura na meranie viskozity pri nízkých teplotách a malom šmykovom spáde je zvyčajne usporiadaná tak, že kvapalina nevytéká z kapiláry působením gravitačnej sily, ale naopak, kvapalina je do kapiláry nasávaná pod tlakom o definovanej hodnotě.The apparatus for measuring low temperature viscosity and low slope is usually arranged so that the liquid does not flow out of the capillary by the force of gravity, but vice versa, the liquid is sucked into the capillary at a defined pressure.

Meranie viskozity pri nízkých teplotách so sebou prináša problém přesného temperovania a zvýšenie prevádzkových nákladov na výrobu chladu, lebo skúška trvá viac než 16 hod.Measuring low temperature viscosities poses the problem of accurate tempering and increased operating costs for cold production, as the test takes more than 16 hours.

Typické sú dva spůsoby usporiadania meracej aparatury:Typical are two ways of measuring instrument arrangement:

V Dewardovej nádobě sa v chladívej kvapaline temperuje len vzorka, zatial' čo kapilára nie je temperovaná. Tento sposob je použitelný len pri nehlbokých teplotách, přibližné do —10 °C a pri málo viskóznych kvapalinách, kde čas potrebhý na naplnenieIn the Deward vessel only the sample is tempered in the coolant while the capillary is not tempered. This method is only applicable at low temperatures, up to about -10 ° C and low viscosity fluids where filling time

Claims

SUBJECT

Vessel for measuring viscosity at temperatures below 0 ° C, characterized in that the capillary tube (2) extending from the side of the measuring vessel (1) is relatively short, up to approximately 60 sec. For more viscous liquids, or at temperatures below -10 ° C, the capillary filling time is so long that the temperature of the liquid to be measured changes in the capillary space, thereby distorting the measured viscosity value.

Such an arrangement of the apparatus is described e.g. in UAE SP 418, p. 34th

A second way of arranging the apparatus is that the entire measuring apparatus is located in the cooling chamber. Such an arrangement is described e.g. in Wear, Vol. 56, No 1, 1979, p. 25 or in the National Petroleum Refiners Association FL 78-83, p. 20. Although such an arrangement allows perfect tempering, it is quite large and its operation requires increased production costs for the cold.

These disadvantages can be overcome if a measuring vessel according to the invention is used to measure the viscosity. It is an object of the present invention to provide a vessel for measuring viscosity at temperatures below 0 [deg.] C. having a side tube for temperature and aeration, and a measuring capillary connected through an airtight seal.

The container is shown in FIG. 1. The overall arrangement of the measuring apparatus is shown in FIG.

Second

The measuring vessel 1 has a tube 2 on its side, into which a thermometer 3 is placed, extending directly into the sample space 4. The measuring tube 1 is connected concentrically to the measuring vessel 1 via an airtight seal.

The advantage of the measuring vessel 1 is that it allows such an arrangement of the apparatus that it is possible for the entire measuring apparatus, i. j. immerse both the measuring vessel 1 with sample 4 and the measuring pipette 5 in the tempering liquid. The tube 2 for placing the thermometer 3 protrudes above the surface of the tempering liquid, thereby allowing the space above the level of the sample to be measured to be aerated. The design of the measuring vessel is unpretentious and operation, due to the small volume of the tempering fluid, is less energy intensive.

OF THE INVENTION intended for temperature measurement and aeration and a measuring capillary (5) is connected through an airtight seal.