Methods for preform and tube draw based on controlling forming zone viscosity determined by calculating a holding force exerted by the glass component in the forming zone on the strand being drawn below. The holding force may be calculated by determining a gravitational force applied to the strand and a pulling force applied to the strand by a pulling device, where the holding force is equal to the opposite of the algebraic sum of the gravitational and pulling forces. The holding force may also be calculated by measuring a stress-induced birefringence in the strand at a point between the forming zone and the pulling device, determining an amount of force applied to the strand at the point corresponding to the birefringence, and calculating the holding force by correcting the amount of force for a gravitational effect of the weight of the strand between the forming zone and the point.

A fluid characterization measuring instrument is disclosed that comprises a sample vessel for a bulk complex sample fluid having a capacity that is substantially larger than a domain size of the complex sample fluid and that is sufficiently large to cause bulk scattering effects to substantially exceed surface effects for the complex fluid sample, a coherent light source positioned to illuminate the bulk complex sample fluid in the sample vessel and a first fibre having a first end positioned to receive backscattered light from the sample after it has interacted with the sample. The first fibre can also be positioned close enough to an optical axis of the coherent light source and to the sample vessel to substantially decrease a contribution of multiply scattered light in the backscattered light. The instrument can further comprise a first photon-counting detector positioned to receive the backscattered light from a second end of the fibre, correlation logic responsive to the first photon-counting detector and single-scattering fluid property analysis logic responsive to the correlation logic and operative to derive at least one fluid property for the sample fluid.

A fluid characterization measuring instrument is disclosed that comprises a sample vessel for a bulk complex sample fluid having a capacity that is substantially larger than a domain size of the complex sample fluid and that is sufficiently large to cause bulk scattering effects to substantially exceed surface effects for the complex fluid sample, a coherent light source positioned to illuminate the bulk complex sample fluid in the sample vessel and a first fibre having a first end positioned to receive backscattered light from the sample after it has interacted with the sample. The first fibre can also be positioned close enough to an optical axis of the coherent light source and to the sample vessel to substantially decrease a contribution of multiply scattered light in the backscattered light. The instrument can further comprise a first photon-counting detector positioned to receive the backscattered light from a second end of the fibre, correlation logic responsive to the first photon-counting detector and single-scattering fluid property analysis logic responsive to the correlation logic and operative to derive at least one fluid property for the sample fluid.

A method and device for controlling viscosity of asphalt rubber based on a current variation are provided. The method includes processing asphalt rubber raw materials with a first preset proportion, and shearing the processed asphalt rubber; obtaining a shearing current, pumping and discharging the sheared asphalt rubber; obtaining a discharging current, and obtaining the viscosity of the pumped asphalt rubber according to the discharging current and the viscosity-discharging current correlation relationship. The method includes comparing the viscosity with a preset viscosity; outputting the pumped asphalt rubber as finished asphalt rubber when the viscosity is equal to the preset viscosity. The method includes adjusting the viscosity according to the discharging current. Double-current control is adopted, so that the whole-process control of the processing viscosity of the asphalt rubber is realized, and the control accuracy of the viscosity is improved.

The invention relates to a process for the preparation of polypropylene having: a molecular weight of 450,000-950,000, a molecular weight distribution of 3-6, and xylene soluble content of 2-6 wt %, by converting propylene into the polypropylene without pre-polymerization in the presence of a polymerization catalyst under a condition where the volume ratio of H.sub.2 to propylene is at most 0.0020, wherein the catalyst comprises a catalyst component and a co-catalyst, wherein the catalyst component is obtained by a process wherein a compound with formula Mg(OAlk).sub.xCl.sub.y wherein x is larger than 0 and smaller than 2, y equals 2−x and each Alk, independently, represents an alkyl group, is contacted with a titanium tetraalkoxide and/or an alcohol in the presence of an inert dispersant to give an intermediate reaction product and wherein the intermediate reaction product is contacted with titanium tetrachloride in the presence of an internal donor.

Viscosity and other properties are determined at desired temperatures in drilling mud and other fluids by using a versatile cavitation device which, operating in the cavitation mode, mixes and heats the fluid to a specified temperature, and, operating in the shear mode, acts as a spindle for application of Couette principles to determine viscosity as a function of shear stress and shear rate. The invention obviates the practice of adjusting rheology of a drilling fluid by passing it through the drill bit. Drilling fluid may be managed by a “straight-through” method to the well, or by placing the cavitation device in a loop which isolates an aliquot of known volume and circulating the fluid through the loop including the cavitation device. A controller may be programmed to manage the viscosity and other properties at various temperatures by controlling the power input and angular rotation of the “spindle” (which has cavities on its cylindrical surface), and feeding viscosity-adjusting agents and other additives to the fluid. Data may be collected from the loop and used in the “straight-through” mode until it is determined that conditions require a new set of data, or the loop may be used continuously. The system may be used with a supplemental viscometer, density meter, and other instruments.

Viscosity and other properties are determined at desired temperatures in drilling mud and other fluids by using a versatile cavitation device which, operating in the cavitation mode, mixes and heats the fluid to a specified temperature, and, operating in the shear mode, acts as a spindle for application of Couette principles to determine viscosity as a function of shear stress and shear rate. The invention obviates the practice of adjusting rheology of a drilling fluid by passing it through the drill bit. Drilling fluid may be managed by a “straight-through” method to the well, or by placing the cavitation device in a loop which isolates an aliquot of known volume and circulating the fluid through the loop including the cavitation device. A controller may be programmed to manage the viscosity and other properties at various temperatures by controlling the power input and angular rotation of the “spindle” (which has cavities on its cylindrical surface), and feeding viscosity-adjusting agents and other additives to the fluid. Data may be collected from the loop and used in the “straight-through” mode until it is determined that conditions require a new set of data, or the loop may be used continuously. The system may be used with a supplemental viscometer, density meter, and other instruments.

An apparatus for checking a need for maintenance of a viscometer measuring consistency of suspension comprises a rigid rod and an elongated cavity in a measuring arm of the viscometer. The rigid rod is matched with the cavity for the rod to be movable in the cavity. The cavity is configured to become mismatched with respect to the rod in response to a bending of the measuring arm, the mismatch indicating a need for maintenance of the viscometer.

Provided is a method for predicting kinematic viscosity of a fraction of a crude oil to optimize selection of crude oils. The method includes receiving parameters of the crude oil, such as Vacuum Residue yield and Conradson Carbon Residue (CCR), content as an input. The method also includes determining kinematic viscosity of the fraction of the crude oil at a first predetermined temperature based on a first correlation model between the physical parameters of the crude oil and the kinematic viscosity at the first predetermined temperature. The method further includes generating the kinematic viscosity of the fraction of the crude oil at the predetermined temperature based on the first correlation model corresponding to the input. Also provided is a system for predicting kinematic viscosity at a predetermined temperature to optimize crude oil selection. Further provided is a method for estimating an amount of cutter stock for crude oil processing.

Provided is a method for predicting kinematic viscosity of a fraction of a crude oil to optimize selection of crude oils. The method includes receiving parameters of the crude oil, such as Vacuum Residue yield and Conradson Carbon Residue (CCR), content as an input. The method also includes determining kinematic viscosity of the fraction of the crude oil at a first predetermined temperature based on a first correlation model between the physical parameters of the crude oil and the kinematic viscosity at the first predetermined temperature. The method further includes generating the kinematic viscosity of the fraction of the crude oil at the predetermined temperature based on the first correlation model corresponding to the input. Also provided is a system for predicting kinematic viscosity at a predetermined temperature to optimize crude oil selection. Further provided is a method for estimating an amount of cutter stock for crude oil processing.