2

Features & Benefits

Ashcroft

®

Test Gauges

Dresser engineers have devel-oped a new generation of test gauges to meet the exacting needs of instrument engineers and quality specialists. The new Ashcroft ? MicroSpan
™ adjustment for ease inspan calibration. This device per- mits precise adjustments to achieve exact span calibration from 0 to 100% of scale. The microme- ter screw attached to the industrial slide will vary the span by approximately ? Hydraulically staked movement pro-vides improved stability. The movement, with Teflon
® coatedgears and bearings, uses a unique hydraulic staking operation to ensure a rigid movement frame that resists shift due to shock and vibration. High and low pressure movement stops are standard to protect the gauge against calibration shifts caused by accidental overpressure, and to limit pointer rotation.? Improved dial and pointer results inexcellent readability. Larger numer- als, additional graduations and a highly polished mirror band
® testgauge can be used as a transfer standard for periodically checking the accuracy of pressure instru- ments or as a laboratory instrument for research and test labs. The wealth of new features make it an excellent test gauge for process applications where high accuracy in pressure measurement is essential. ? External adjustable dial facilitatescompensation for tare or zero adjustment on standard case style Type 1082(*)S only.? Temperature compensated move-ment that significantly reduces temperature error. Conventional test gauge accuracy is adversely affected as the ambi- ent temperature varies from that at which the gauge was calibrated. This inaccuracy can be as much as 0.02%/°F or
1 �
2 %per 360°rotation.? The long life bourdon tube is capa-ble of sustained accuracy, yet is suitable for process applications. The Ashcroft test gauge uses the Ashcroft Duragauge
® pressuregauge bourdon tube – perhaps the most highly developed bourdon tube in the world. Proven and refined by years of rugged service in demanding process applications around the world, this outstanding pressure element is standard in all 4
1 �
2 ,� 6� and 8
1 �
2 � size Ashcrofttest gauges.
1 �
2 % for a 25°F temper-ature change. The 4
1 �
2 � and largerAshcroft test gauges include a spe- cial bimetallic element which automatically reduces ambient temperature errors to less than 0.005% per degree F. Some manufacturers reduce tem- perature error by using NiSpan C
® for bourdon tubes. This material is subject to serious corrosion prob- lems in some applications. The Ashcroft temperature compensated movement allows use of Monel
® bourdon tubes for corrosion resis- tance superior to NiSpan C while still providing excellent tempera- ture stability.
*Bourdon tube designation (see page 4). CONTENTS
Introduction . . . . . . . . . . . . . . . . . . . . .2Standard Case Styles . . . . . . . . . . . . .4 Optional Case Styles . . . . . . . . . . . . .5 Accessories and Optional Features .6 Product Selection Informtion . . . . . .7 To Order a Gauge . . . . . . . . . . . . . . . .8 Standard Ranges . . . . . . . . . . . . . . . .9 Gauge Case Dimensions . . . . . . .10-11 FRONT VIEWStandard Case StyleType 1082 (*)S