Fine­ness of Grind Gages

Also called grind gages and Heg­man gages. Many types of solid mate­rials must be ground or milled into finer par­ti­cles for dis­per­sion in appro­pri­ate liquid vehi­cles. The phys­i­cal prop­er­ties of the result­ing dis­per­sions, often called \"grinds\", depend not only on the actual size of the indi­vi­d­ual par­ti­cles, but also on the degree to which they are dis­persed.

The Fine­ness of Grind Gage is used to indi­cate the fine­ness of grind or the pres­ence of coarse par­ti­cles or agglom­er­ates in a dis­per­sion. It does not deter­mine par­ti­cle size or par­ti­cle size dis­tri­bu­tion.

Grind gages are used in con­trolling the pro­duc­tion, stor­age, and appli­ca­tion of dis­per­sion prod­ucts pro­duced by milling in the paint, plas­tic, pig­ment, print­ing ink, paper, ceramic, phar­ma­ceu­ti­cal, food, and many other indus­tries.

The Fine­ness of Grind Gage is a flat steel block in the sur­face of which are two flat-bot­tomed grooves vary­ing uni­formly in depth from a max­i­mum at one end of the block to zero near the other end. Groove depth is gra­d­u­ated on the block accord­ing to one or more scales used for mea­sur­ing par­ti­cle size.

Most gages will have one scale marked in either mils or microns.
1 mil = 25.4 microns
1 mil = 0.001 inch
1 micron, μm = 0.001 mm or 10-6 m

The Heg­man scale or Natio­nal Stan­dard scale may be abbre­vi­ated "NS" on the gage. The scale ranges from 0 to 8 with num­bers increas­ing as the par­ti­cle size decreases.
0 Heg­man = 4 mil/100 micron par­ti­cle size
4 Heg­man = 2 mil/50 micron par­ti­cle size
8 Heg­man = 0 mil/0 micron par­ti­cle size

BYK-Gard­ner offers a wide vari­ety of grind gages vary­ing in scales, num­ber of grooves, length and width of grooves and size of the block.

Comes in a reus­able stor­age box to pre­vent dam­age.

Pro­ce­dure

Place a slight excess of sam­ple in the deep end of the groove, and with the straight-edge scraper pro­vided, draw the sam­ple toward the shal­low end of the groove. Rat­ings are in terms of the point on the scale where the over­size par­ti­cles, or fur­rows made by them, first appear in sub­s­tan­tial con­cen­tra­tion.

Made of cor­ro­sion resis­tant stain­less steel

For Cer­ti­fi­ca­tion Ser­vice see page 269.

Comes com­plete with:
Grind block
Scraper
Reus­able Stor­age Case

*Designed to com­ply with ISO method 1524

Fine­ness of Grind Gages