AS NZS 1301.447:2016 pdf free
AS NZS 1301.447:2016 pdf free.Methods of test for pulp and paper
Prior to performing the following calibration procedure, the variable-area flow tubes and the air-leak adjustment valves on the older-style instruments shall first be calibrated in Sheffield Units using calibration orifices provided by the manufacturer. In operation, the instrument shall always be checked against the manufacturer’ s calibration orifices prior to using the flow tube, to establish a calibration graph or chart in millilitres per minute.
To calibrate a variable-area flow-measuring device, disconnect the test assembly from the downstream end of the rubber or plastic tubing and connect in its place the soap-bubble meter. Set the valves to deliver air through the flowmeter to be calibrated and then through the soap-bubble meter. Adjust the needle valve to give a conveniently measurable air flow and ensure that the flow rate remains constant. Rapidly squeeze the rubber bulb at the bottom of the volumeter so that a soap bubble enters the volumeter tube.
The volumeter range should be chosen so that the time taken for the bubble to pass from the first to the second graduation is longer than 30 s. .
To calibrate an electronic flow-measuring device, connect the soap-bubble meter to the calibration plate device (5.2) placed beneath the measuring head. Set the valves to deliver air through the flowmeter to be calibrated and then through the soap-bubble meter. Adjust the needle valve to give a conveniently measurable air flow and ensure that the flow rate remains constant. Rapidly squeeze the rubber bulb at the bottom of the volumeter, so that a soap bubble enters the volumeter tube. The volumeter range should be chosen so that the time taken for the bubble to pass from the first to the second graduation is longer than 30 s.
Repeat the procedure at about six different air flow rates distributed over the upper 80 % of the flowmeter measurement range.AS NZS 1301.447 pdf free download.
