[의류제품] Headspace Resistance Standards for the Shirley Developments Ltd. Micromat Tester 출판일 : 1999.04.01 저자 : Joseph G. Montalvo JR, Sherman E. Faught 서지사항 : Textile Research Journal, Volume 69, No 4(1999), 269-277 페이지 등록일 : 2012.11.16 I 조회수 : 133 작성자 : admin |
High precision headspace resistance standards (HRS) are developed for the Micromat
model of the Shirley Developments Ltd. fineness and maturity tester. The Micromat measures
cotton fineness and maturity based on the principle of air permeability through a fixed mass
of fibers at two different stages of compression. Differential pressures are the quantities
measured, and are related to maturity and fineness by appropriate equa tions. HRS are
mechanical air flow restrictors: we use narrow diameter tubes, needle valves, and metal
frits. Air flow rates through the calibration cotton are adjusted to give the declared
differential pressure values, and these flows are exactly "transferred" to the HRS. The
calibration transfer coefficient β, defined as the ratio of differential pressure through the HRS
material to differential pressure through the calibration cotton, is fixed at β > 1 to increase
sensitivity to Micromat drift. Routine analysis of two sets of cottons is presented based on
HRS calibration and control. There is no drift in in strumental readings over the 3-week and
6-week periods required to analyze the sets of cottons.
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