20DAX40 High Pressure U-Tube Manometer 

The 20DAX40 High Pressure U-Tube Manometer is designed to measure pressure, vacuum, or differential pressure with a maximum working pressure of 400 PSI. 

This manometer is very rugged in construction and is intended primarily for high line pressure operation. Only carefully selected fully annealed glass tubes are used.

The position of the manometer scale allows for quick and accurate reading of the indicating column. 

The U-tube manometer is the primary basic standard for pressure measurement. 

Pressure measurement is achieved by balancing the vertical head of the indicating liquid against the pressure to be measured. Since there are no cams, gears, or levers in the manometer, the readings are very accurate. 

Construction 

The manometer body has an aluminum channel, which is connected to stainless steel end blocks. The wetted parts are Type 304SS. 

Each end block of the glass tube is sealed with a fluoroelastomer gasket and supported at intervals to prevent the glass tube from deforming under increased pressure. This manometer uses two separate straight tubes instead of the traditional U-shaped glass tube. To connect the two vertical glass tube legs to form a U-shape, the lower end block of the manometer is cross-drilled.

The background of the manometer scale is a white non-reflective satin finish, with black graduations and characters. The scale is adjustable for zeroing the indicating liquid. 

A shipping cover protects the device from dust and moisture and shields the operator in case the indicating tube breaks due to excessive pressure. 

Standard pressure connections are made with 1/4-inch female pipe threads on the top of the upper end block. A drain plug at the bottom of the lower end block allows for the removal of the manometer indicating liquid and cleaning of the glass indicating tube. The instrument surface is finished in a durable black urethane texture. 

Specifications 

Scale 

A - Linear inches and tenths 

B - Inches of water using mercury 

C - Pounds and tenths (PSI) using mercury 

F - Linear centimeters and millimeters 

G - Inches and tenths of water using Meriam 827 Red Oil 

H - Tenths of an inch of water using Meriam 175 Blue Fluid 

I - Fifths of an inch of water using Meriam 295 Red Fluid