Burkert 325429 (Type 6628) is a direct-acting, media-separated 2/2 or 3/2-way rocker solenoid valve designed for the control of aggressive liquids and gases in medical analysis technology, the food industry, and the chemical industry during dosing, filling, mixing, and distribution. The medium is only in contact with the housing and seal material through the separating diaphragm. With its TwinPower actuator, robust fitting, and 22 mm width, this valve meets the most stringent requirements. The tried-and-tested rocker technology is characterised by full back pressure tightness, good flushability, and a low internal volume.

General Technical Data

Product Properties	Specification
Seal Material	FFKM, FKM or EPDM
Valve Body Material	PEEK, PPS or PVDF (PP on request)
Internal Volume	Bürkert sub-base: from 280 μl Hose connector: from 500 μl Threaded body: from 500 μl
Orifice	DN 2.0 (Vac...5 bar) DN 3.0 (Vac...3 bar)
Switching Time	Opening: approx. 25 ms (pressure build-up 0...10 %) Closing: approx. 25 ms (pressure reduction 100...90 %)
Power Supply	12 V DC, 24 V DC
Duty Cycle	100 % continuous operation
Nominal Power	5 W
Medium Temperature	FKM: 0 °C...+55 °C FFKM: +10 °C...+55 °C EPDM: -10 °C...+55 °C
Viscosity	Max. 21 mm²/s
Degree of Protection	IP54 with cable or cable plug Type 2507 IP30 with rectangular cable plug Type 2505

Approvals and Conformities

• FDA: All wetted materials are compliant with the Code of Federal Regulations published by the FDA (on request only with seal material EPDM).
• USP: All wetted materials are biocompatible according to USP Chapter 87/88 Class VI (on request only with body material PPS/PEEK and seal material EPDM).

Circuit Functions

Symbol	Description
CF A	2/2-way solenoid valve, Direct-acting, Normally closed
CF B	2/2-way solenoid valve, Direct-acting, Normally open
CF T	3/2-way solenoid valve, Direct-acting, Flow direction optional, Universal

Material Specifications

No.	Element	Material
1	Fastening screw M3	Stainless steel
2	Coil	Epoxy
3	Valve body	PPS
4	Diaphragm (Wetted)	FFKM, FKM or EPDM
5	Valve body (Wetted)	PEEK, PPS or PVDF
6	Sub-base seal (Wetted)	FFKM, FKM or EPDM

Installation and Safety

Danger – High Pressure

Risk of injury from high pressure in the system. Before loosening lines or valves, switch off the pressure and drain the lines.

Risk of Escaping Medium

Ensure that the seals provided fit properly. Only use manifolds of sufficient quality and with a flat surface.

Fluidic Installation:

• Installation position: any, preferably with actuator on top.
• Clean pipelines and flange connections.
• Install dirt trap in the direction of the current before the valve (mesh width 5 μm).
• Fasten the valve. Tightening torque approx. 0.9 Nm for metric screws.

Dimensions

Sub-base variant with connector plug form B

Threaded variant with rectangular plug Type 2505