ChemTec Equipment Company - EFV Series Specs

Adjustable Excess Flow Valve for preventing uncontrolled flows of gases and liquids.

Controls excessive flows

Fitting Failure

Regulator failure

Hydraulic control

Gas Analyzers

Toxic Gas and Liquid Releases

Features

Controlled Bleed, Resets Automatically
Field Adjustable
Positive Shut-off
Attitude Variable Mounting

Function: Restricts or Shuts Off Flow
Output: switch contact optional
Materials: 316ss or Brass Body

Operation

Flow enters the unit and makes a right angle to the outlet port across the nose of a magnetic piston. The piston is held in place by attraction to an adjusting screw magnet. A pressure differential is created by flow across the piston. When the differential is great enough, the piston slides to a seat at the outlet port. The flow rate at which the piston actuates can be changed externally by turning the adjusting screw, thereby changing the piston's relationship with the flow stream.

In this auto reset model after actuation, the piston rests on a metal to metal seat which allows a controlled bleed. To reset the unit, pressure must be equalized on both sides of the piston. If the source is turned off, either upstream or downstream, the bleed will equalize the pressure and the valve will automatically reopen by magnetic repulsion from the fixed magnet located in the valve body.

For positive shut-off an elastomer is used on the nose of the piston. When it comes to rest on the seat it provides a bubble tight closure. To reopen the valve there are two options.

The upstream pipeline must be bled to atmosphere if the line downstream is at atmosphere.
A by-pass line with an on/off valve must be installed to port the upstream pressure to the downstream pipeline to equalize the pressure.

Our MRS series is available with the by-pass system as an integral part of the unit.

Actuation points for air at 68 F and 15 PSIG.
Corrections must be used for other gases, line pressures and temperatures.
Please consult your representative or the factory.

CALIBRATION RANGE

Model Adjustable
Range
Air SLPM (SCFM) Adjustable
Range
Water LPM (GPM) Port
Size
FNPT

EFV-125 0.5 to 155.70
(0.018 to 5.5) 0.015 to 4.5
(0.004 to 1.2) 1/8"

EFV-250 4 to 1132
(0.14 to 40) 0.100 to 15.1
(0.026 to 4.0) 1/4"

EFV-375 85 to 1840
(3.0 to 65) 0.380 to 15.1
(0.100 to 4.0) 3/8"

EFV-500 142 to 2123
(5.0 to 75) 1.90 to 37.8
(0.50 to 10.0) 1/2"

EFV-750 425 to 3681
(15.0 to 130) 3.80 to 75.7 (1.0 to 20.0) 3/4"

PRESSURE LOSS TABLE

Model Set Point DP to Atmosphere
BARD (PSID)

Air
SLPM (SCFM) Water
OPM (GPM)

EFV-125 0.5 (0.018)
75 (2.63)
155.7 (5.5) 0.015 (0.004)
2.65 (0.70)
4.50 (1.20) 0.08 (1.2)
0.11 (1.6)
0.21 (3.0)

EFV-250 4 (0.14)
500 (17.50)
1132 (39.62) 0.1 (0.26)
5.0 (1.32)
15.1 (3.99) 0.21 (3.0)
0.41 (6.0)
0.83 (12.0)

EFV-375 85 (2.98)
900 (31.50)
1840 (64.40) 0.38 (0.10)
10.0 (2.64)
15.1 (3.99) 0.10 (1.5)
0.28 (4.0)
0.83 (12.0)

EFV-500 142 (4.97)
1000 (35.00)
2123 (74.31) 1.9 (0.50)
25.0 (6.60)
37.8 (9.98) 0.07 (1.0)
0.28 (4.0)
0.48 (7.0)

EFV-750 425 (14.88)
1800 (63.00)
3681 (128.84) 3.8 (1.00)
4.7 (1.24)
75.7 (19.98) 0.14 (2.0)
0.21 (3.0)
0.34 (5.0)