model Tx multiple flow tube PTFE meters

model Tx multiple tube PTFE/Glass flow meter for low flow rate measurement

Design Features

constructed of inert materials: borosilicate glass, PTFE and PCTFE
chemically inert wetted parts within mechanically rigid frame
rib-guided or fluted metering tubes facilitate stable/accurate readings
OPTIGRAD™ scales minimize parallax and eye fatigue
simple means of panel mounting
interchangeability of flowtubes and floats
conveniently overlapping flow ranges available in both standard millimeter and direct reading scales.

Model Tx Multiple Tube PTFE-Glass flow meters combine the convenience of multiple tube meters with the unique design features of single tube PTFE-Glass flow meters. These meters are available with the same interchangeable 65mm or 150mm glass flow tubes used in single tube designs and they are available with or without built-in PTFE needle valves. Wetted inert components are surrounded by structurally rigid anodized aluminum. The resultant design represents a unique combination of a rugged mechanically rigid frame and chemically inert wetted parts.

They are ideal for applications where several streams of corrosive gases or liquids are to be metered in individual channels or as a controlled mixer in manifolded models.
Flow tubes for these meters are available with two types of scales, suitable for different types of applications

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DIRECT READING SCALES

Direct reading scales are indicating flow rates of liquids and gases,in engineering units such as [mL/min], standard cubic feet per hour [scfh] etc. Such scales are designed exclusively for a specific gas or liquid at a given set of pressure and temperature parameters, and are valid for the associated units of flow only. The convenience of direct reading scale designs should be weighed against the resultant limitations of applicability. Generally, direct reading scales are most suited to OEM applications.

UNIVERSAL MILLIMETER (CORRELATED) SCALES

Millimeter scales indicate the vertical position of the spherical float within the metering tube as the flow increases or decreases.

It is necessary to use flow tables or graphs supplied, to correlate float referenced readings with actual volumetric flow rates.

The advantage of Universal type scales is the ability to utilize the use of a given flow meter for a great number of different fluids at diverse pressure and temperature conditions, generally preferred in applications in laboratories, etc.

BUILT-IN VALVES

Meters are available with built-in needle valves (CVT™ ), high precision metering valves (HRT™) with “non-rising stems”, or with no valves. The higher cost of HRT™ valves is justified whenever high sensitivity control and resolution are desirable particularly in conjunction with metering tubes of very low flowrates.

When meters with valves are ordered the valve cartridges are installed at the inlet. For vacuum service it is recommended that meters are ordered with valves at the outlet.

SPECIFICATIONS

STANDARD ACCURACY ±2% FS (mm scales - except 032/042 flow tubes); ±5% FS (direct reading scales and 032/042 flow tubes)

CALIBRATED ACCURACY ±1% FS

REPEATABILITY ±0.25% FS

USEFUL FLOW RANGE 10:1 minimum with one float

MAXIMUM OPERATING PRESSURE 100 psig (6.7 bars)

MAXIMUM OPERATING TEMPERATURE 150°F (65°C)

LEAK INTEGRITY individually pressure and leak tested and certified to a rating of 1x10^-7 sccs helium

MATERIALS OF CONSTRUCTION

FLOW TUBES heavy walled borosilicate glass (glass or sapphire floats recommended)

FITTINGS IN CONTACT WITH FLUIDS virgin PTFE and PCTFE

SIDE PANELS aluminum, black anodized

FRONT SHIELD 1/8 inch thick clear

BACK PLATE 1/8 inch thick white acrylics

O-RINGS PTFE

CONNECTIONS 1/8 inch NPT female inlet and outlet connections; optional glass hose nipples or compression fittings are available