39 results about "Mean stress" patented technology

This is a connection device comprising an insulating case and it defines at least one housing and various connection openings and work openings, an electrical contact plate, a screw mounted in the housing, and clamping means stressed by the screw in order when required to immobilize together the conducting element and the contact plate. The case comprises means for retaining the screw inside the housing so that only the head of the screw is accessible from the outside through the work opening, the clamping means being completely insulated from the outside by the case, and rotation of the screw moves the clamping means translationally inside the housing between two separate positions at a distance from each other.

An object of the present invention is to control crack propagation, either by predicting shaft dovetail crack propagation with high accuracy, or by determining operation conditions under which the crack does not extend. The crack propagation prediction system includes an operation processing unit, an interface unit, and a memory unit. The operation processing unit includes a stress calculation unit that calculates the mean stress generated in the shaft dovetail, a factor range calculation unit that calculates the stress intensity factor range for the crack in the shaft dovetail, and a crack propagation amount calculation unit that calculates an amount of the shaft dovetail crack propagation for an arbitrary time period, from the obtained mean stress and the stress intensity factor range, an operation pattern, an operation time, and data on the crack. The stress calculation unit includes as individual calculation units that calculate separately different types of mean stress, a contact surface pressure stress calculation unit, a thermal stress calculation unit, and a residual stress calculation unit, as well as a mean stress calculation unit that sums these mean stresses.

The present invention provides a displacement pressure determination method and system for constant-rate and constant-pressure chemical flooding experiments. The method is: obtain multiple pressure data in the constant-rate chemical flooding stage, calculate the cumulative injection pressure value, and According to the minimum pressure data and maximum pressure data, select multiple average pressure values, and calculate multiple pressure holding times corresponding to multiple average pressure values, and then conduct constant pressure displacement experiments to obtain corresponding multiple cumulative injection data. Combine multiple average pressure values ​​to generate a curve; according to the cumulative injection data obtained in the constant-rate displacement experiment, combine the curves to calculate the displacement pressure data. The method and system for determining the displacement pressure of the constant speed and constant pressure chemical flooding experiment of the present invention can obtain the displacement pressure suitable for the constant pressure displacement experiment through the constant speed and constant pressure experiment. Under the condition of a certain cumulative injection volume, the results of constant velocity and constant pressure experiments can be effectively compared and transformed, and then play a guiding role in mine practice.

The invention discloses a method for predicting the fatigue life of a straw throwing impeller, including fluid-solid coupling and stress analysis of the throwing impeller; a double-parameter nominal stress model; a double-parameter nominal stress model of the straw throwing impeller; and a Miner fatigue cumulative damage model. The beneficial effect of the present invention is: adopt the two-parameter (average stress Sa Sm and stress range Sa) nominal stress model, Miner fatigue cumulative damage model and fatigue life logarithmic normal distribution model to combine throwing impeller fatigue life prediction method, simultaneously for Accurately obtain the random cyclic load on the throwing impeller, calculate and analyze its stress by using the fluid-solid coupling method, and use this as a basis to predict the fatigue life of the throwing impeller.

The invention discloses a soft-measurement method of quality of espresso coffee. A sensing information measurement system is built on a coffee machine. The sensing information measurement system includes a weighing module, a thermal resistor, a thermocouple, a pressure gauge and a vision sensor. The thermal resistor is used to measure temperature of an outer wall of a boiler. The thermocouple is used to measure temperature of coffee liquid of an outlet of the coffee machine. The pressure gauge measures pressure of the outlet of the pump. The visual sensor is used to obtain color information ofthe coffee liquid of the outlet. Sensor information is processed, and indexes of average boiler temperature, average outlet temperature, time in which the outlet temperature reaches a stable state, water discharging time, brewing-boiling duration, average pressure, an average flow rate, time in which a flow rate reaches a stable state, coffee outlet color changes and the like are calculated. Upper / lower-limit reference ranges of the indexes are determined through historical statistics of the coffee sensor information and a coffee extraction process mechanism. A priori statistical knowledge iscombined for soft measurements on the quality of the espresso coffee, and arbitrariness and empirical dependence of human tasting are eliminated.