Gauges

Ashcroft^® Accessories

Throttling Devices
A throttling device should be used when a pressure gauge is subjected to rapid pressure fluctuations, which make the gauge difficult to read because of rapid pointer movement. Such a device reduces pressure impact, slows the speed and range of pointer movement, and prolongs gauge life.

Throttling effect is obtained by installing a restricting orifice between the gauge socket connection and the bourdon tube. Several types are available: throttle screws, pressure snubbers, pulsation dampeners, Gauge Saver® and the Campbell MICRO-BEAN.

Severe service applications are characterized by the presence of significant levels of pressure pulsation and/or vibration. Gauges should be protected from severe pressure pulsation by the inclusion of a dampener such as a throttle plug/screw or a porous metal snubber. If the pulsation is extreme, a liquid-filled gauge, with dampener, should be used. A liquid-filled gauge will also last signifcantly longer than a comparable dry gauge when vibration is present. If the vibration levels are extreme, the only solution may be to remotely mount the gauge away from the source of vibration. In that case flexible tubing may be used to connect the gauge to the pressure source.

PRESSURE SNUBBER

Type Number	NPT Conn.	Material		Max psi
Type Number	NPT Conn.	Housing	Filter Disc	Rating
25-1112B 50-1112B	¼ ½	Brass	316 SS	10'000
25-1112S 50-1112S	¼ ½	303 SS	316 SS	15'000

Used for dampening and filtering, the snubber has a metal disc available in four standard grades of porosity. The one best suited for the application can be selected from the chart, using the same guidelines as for throttle screws. Due to the large filter area, the snubber has less tendency to clog than orifice-type devices. All-metal construction permits the snubber to be washed in a variety of common solvents.

Please refer to the CHEMIQUIP section for more detailed information on Pressure Snubbers

THROTTLE SCREWS

The simplest means of providing a restriction in the socket, a throttle screw, should be ordered with the gauge. Threaded or pressed into an instrument socket, the throttle screw orifice selected is based on the viscosity of the pressure fluid, rapidity of the fluctuations, and the amount of dampeninig effect desired.		A smaller orifice should be used for low viscosities, high frequencies, high pressure and reduced pointer amplitude. To accommodate these variables, throttle screws are available in these sizes: 0.006, 0.0135, 0.020, 0.031, 0.040 and 0.070 inches, in brass or stainless steel. When orifice size or service is not specified, a 0.031 -inch orifice will be supplied.

PULSATION DAMPENER

Threads onto a gauge socket and provides restriction by means of a moving pin, which may be placed in either of five different sized holes, and thus allows the user to vary the amount of dampening to suit requirments. The pulsating pressure moves the pin up and down, providing a self-cleaning action. Dampeners are shipped with a pin in the "middle" hole, and may be used in either a vertical or horizontal position. Maximum pressure is 5000 psi.

Type Number	NPT Conn.	Material	Weight
25-1106B	¼	Brass	4
50-1106B	½	Brass	8
25-1106D	¼	Steel	4
50-1106D	½	Steel	8
25-1106S	¼	Stainless Steel	4
50-1106S	½	Stainless Steel	8

SIPHONS

In order to prevent live steam from entering a pressure gauge bourdon tube, a siphon filled with water should be installed between the gauge and the process line. If freezing of the condensate in the loop of a siphon is a possibility, a diaphragm seal should be used to isolate the gauge from the process steam. Also use siphons whenever condensing hot vapors (not just steam) are present.

Pig Tail Siphon-Number 1100 Series, ¼",½" sizes: to 500psi and 400°F.
Coil Pipe Siphon-Number 1098 Series, ¼",½" sizes: to 9550psi and 400°F.

Type Number	NPT Conn.	Material	Capacity
25-1098 I	¼	Iron	500psi & 400°F
25-1098 B	¼	Brass	250psi & 400°F
25-1098 S	¼	ASTM A-106 Seamless Steel Grade A	338psi & 1000° to 3360psi & -20° to 400°F
50-1098 S	½	ASTM A-106 Seamless Steel Grade A	333psi & 1000° to 3000psi & -20° to 400°F
50-1098 SD	½	ASTM A-106 Seamless Steel Grade A	420psi & 1000° to 3740psi & -20° to 400°F
50-1098 CD	½	ASTM A-106 Seamless Steel Grade A	1048psi & 1200° to 9550psi & -20° to 400°F
50-1098 NS	½	Seamless Stainless Steel, Type 316	294psi & 1500° to 3981psi & -20° to 100°F
50-1098 ND	½	Seamless Stainless Steel, Type 316	336psi & 1500° to 5840psi & -20° to 100°F
25-1100 A	¼	Seamless Stainless	500psi & 400°F
25-1100 I	¼	Iron-6 3/8;" Long
25-1100 IL	¼	Iron-8" Long
25-1100 IN	¼	Iron-Angle
25-1100 B	¼	Brass-5 3/8" Long	250psi & 400°F
25-1100 BL	¼	Brass-8" Long	250psi & 400°F

ELECTRIC WARNING CONTACTS

Indicating accuray of Ashcroft Duragauge, above 300psi with contact:
Pointer not carrying contact - 1%
Pointer carrying contact - 1.5%
For ranges below 30psi, add an additional ½% to indicating accuracies.

The Ashcroft® 2265 electric contact is an ideal accessory to turn on a signal light, sound an alarm, or operate a pump or valve. The contacts can easily be set so that a circuit can be closed or opened at a desired pressure or temperature.

Settings can be easily made in the field without removing the instrument from service. Contact adjustment is made externally with a removable key to make the instrument virtually tamper proof.

The contact is designed for easy installation on Types 1279, 1377 and 1379 Duragauge® pressure gauges (either stem or flush mounted), Type 1125 differential pressure gauges, or Type 600A Duratemp dial thermometers. Contacts are equipped with adjustable magnets to eliminate chatter caused by vibration. A plug-in connector with five feet of electrical cable is standard.

Use with Ashcroft Model No.	Description	Availability
		Code		Mounting
		45	60	Mounting
		4½" Dial	6" Dial	Stem	Flush
1279 1377 1379	Duragauge pressure gauge	X X X	- X X	X - X	X X X
1125	D/P gauge	X	X	X	X
				Surface	Flush
600A-02 600A-03 600A-04	Duragauge remote thermometer	X X X	X X X	- X X	X X X

Model	Code	Contact arrangements
2265	XED	High and low contact
	XEE	Double high contact
	XEF	Double low contact
	XEG	"OFF" at low and high, and "ON" in between

CONVERSION KITS (LIQUID-FILL KITS)

For field converting 4½" 1279 and 4½" and 6" 1379 Duragauge® gauges to a sealed case design suitable for either hermetic sealing or liquid filling. Kit Includes O-ring for front case seal. Acrylic window. Elastomeric diaphragm (Buna-N) for rear case seal. Glass filled polypropylene threaded ring for rear of case. 302 stainless steel rear cover and mounting screws. 303 stainless steel and Monel throttle screws. O-ring for socket seal.

HOW TO ORDER CONVERSION KITS (LIQUID-FILL KITS)

4½" size, lower connected - order type A1280 Kit. 4½" size, back connected - order type A1283 Kit. 6" size, lower and back connected - order type A1284 Kit.

TOOLS

Hand Jack Set Gauge pointer remover and a pointer set to secure pointer to the shaft. Type No. 3220
Ring Removal - For the 2½" and 3½" 1009 gauge. Includes 2½" and 3½" wrench and nest. Type No. 1206T
Small Tools - For the 2½" and 3½" 1009 gauge. Includes pointer puller, span adjust wrench, slotted screw driver for pointer adjustment, pointer staker and pinion backup Type No. 1205
Gauge Tool Kit - A complete kit for gauge maintenance. Includes hand jack set, screw driver, five reamers, pin vise holder, wiggler and tweezer all packed in a neat carrying case. Ideal for a gauge maintenance shop. Type No. 1105T

Type A1285 Ring Wrench - 4½"
For installing front or rear threaded rings in 4½" Duragauge gauge.

Type A1286 Ring Wrench - 6"
For installing front or rear threaded rings in 6" Duragauge gauge.

Type A-1287 Cone Tool
For installing diaphragm and garter spring on back connected liquid filled or hermetic sealed Duragauge gauges.

Type A-1281 Socket O-Ring Insertion Tool Kit
For lower connection type 4½" - 1279 and 1379 and 6" - 1379 Ashcroft Duragauge gauges.