Apparatus for Measuring Sieve Dimensions

Introduction

Industries such as cement and drug manufacturing require powders of constant and homogeneous particle size, which are obtained from sieves. The sieves are wire mesh, normally made of metal wires of various diameters with a variety of spacing, depending on the required size of the sieved powder. It is therefore of critical importance to know a priori, the uniformity of spacing and the possibility of any microscopic deformation in the sieve. Presently known method like on line measurement using optical Fourier transform do not preserve the details of the object such as cracks, holes, discontinuous patterns, etc. Another known method making use of laser beam also cannot locate these types of defects. In order to overcome these shortcomings and also to devise a means for accurate measurement of sieve parameters for critical applications, a new methodology using image processing and wavelet transform has been developed.

Salient features:

Apparatus is simple to use without eye fatigue. Gives simultaneously both the diameter of wire and wire spacing. Diameter and spacing of the wire in the sieves can be measured with an accuracy of 1 µm and .uncertainty measurement of ± 2 µm at 95% confidence level Capable of measuring sieve parameters i.e. size and spacing of wire sieves, in a single optial exposure of areas, upto 100 Sq. cm. Of circular or square geometry. Measurement of complete sieve characteristics could be completed within a duration of 30 minutes. Can detect any missing wire or any other defect like bending or kink in the wire. Provide fast and accurate results with ease.

Prospective Users: All industries using material in powder form after crushing and grinding the raw material

Keywords: Sieve, Optical, Image, Signal

Type of Technology: Device with Software

Developed by : Prof. Sekahar Chandra & Dr. Shashi Singh
Department: Instrument Design Development

Contact:

Managing Director
Foundation for Innovation and Technology Transfer (FITT)
Indian Institute of Technology, Delhi
Hauz Khas, New Delhi-110016, INDIA
Tel : 91-011-26597167, 26857762, 26581013, 26597153
Fax : 91-011-26851169
E-mail : drkdpn@gmail.com