Operation With Additional Isolation Valve; Mechanical And Fluidic Installation; Screw Joints - Burkert 8626 Instructions De Service

Operation with additional isolation valve

The proportional valve integrated into the MFC assumes the tight-closure function,
so that an additional isolation valve is not required in the medium circuit. If for
safety reasons, however, an additional isolation valve is placed before or after the
MFC, the drive sequence should be as follows:
Start
1. Connect pressure supply
2. Open isolation valve
3. Set MFC setpoint (normal control operation)
Shut-down
1. Set MFC setpoint to 0 %
2. Close isolation valve when process value of 0 % is reached
Any other sequence could result, on renewed opening of the isolation valve, even
with setpoint zero, in a short flow pulse or, on first setting of the setpoint, significant
overswing.

Mechanical and fluidic installation

Select the available fluidic connections to match the maximum flow rate. Intake
sections are not required. If necessary, we can also supply special sizes,
whereby the dimensioning of the fluidic system with regard to flow and pressure
drop must be taken into account.

Screw joints

The device can on request also be supplied with screw-in joints already
assembled. Please select the matching joint from the table in Appendix B.
Connections at MFC/MFM
Standard screw-in thread
Type G 1/4" G 3/8" G 1/2" G 3/4" NPT 1/4 NPT 3/8 NPT1/2 NPT3/4
8626 X X
8006 X X
8716 X X
8706 X X
8712 X
8702 X
8710 X
8700 X
Special screw-in thread
X X X
X X X
X X X
X X X
X
X
X X X
X X X
X X X
X X X
MFC/MFM - 21