Burkert Type 6281 is a servo-assisted diaphragm valve. A minimum differential pressure is always required for the valve to function. Various diaphragm materials and circuit functions are available depending on the actual application. The standard brass body meets European drinking water requirements. For other markets, dezincification-resistant brass is available. The range includes a variant with a stainless steel body.

To reduce electrical power consumption during operation, coils with integrated Kick-and-Drop (KD) electronics featuring double coil technology are available. The valve can be supplied with manual operation for easy maintenance and commissioning.

• Servo-assisted diaphragm valve up to DN 50
• Vibration-resistant, centrally screwed coil system
• Damped design for quiet closing
• Energy-saving double coil technology with kick and drop variant
• Explosion-proof variants

Circuit Functions

Circuit Function	Description
A (NC)	2/2-way solenoid valve, servo-controlled, normally closed
B (NO)	2/2-way solenoid valve, servo-controlled, normally open

Continuous Operation

Unless otherwise specified on the type label, the solenoid actuator is suitable for continuous operation. During a long downtime, a minimum activity of at least 1–2 switching operations per day is recommended to ensure functional reliability.

Approvals and Conformities

• Explosion Protection: ATEX (II 2G Ex mb IIC T4 Gb, II 2D Ex mb IIIC T130 °C Db) and IECEx variants available.
• North America (USA/Canada): UL Listed for Hazardous Locations, UL Recognized, and CSA approved variants available.
• Drinking Water: Suitable for use in drinking water applications. Materials comply with the assessment principles (UBA) for materials in contact with drinking water (TrinkwasserV).
• DNV GL Classification: Accepted for installation on all vessels classed by DNV GL.
• Oxygen: Optional suitability for gaseous oxygen.

Material Specifications

No.	Element	Material
1	Coil	Polyamide or epoxy
2	Stopper	Stainless steel 1.4113
3	Shading ring	Cu (brass variant) / Ag (stainless steel variant)
4	Magnetic core	Stainless steel 1.4113
5	O-ring	NBR, FKM, EPDM
6	Core seal	NBR, FKM, EPDM
7	Spring	Stainless steel 1.4310
8	O-ring	NBR, FKM, EPDM
9	Diaphragm	NBR, FKM, EPDM
10	Diaphragm holder	PPSGF40, DN 50: brass and stainless steel
11	Valve body	Brass acc. to DIN EN 50930-6 or stainless steel 1.4408 (CF8M)

Dimensions

Standard Threaded Variant

Note: Dimensions in mm. The dimensions F1 and G1 apply to G thread. F2 and G2 apply to NPT thread. F3 and G3 apply to Rc thread.

Installation and Maintenance

Safety Instructions

• Risk of injury from high pressure: Before loosening lines or valves, switch off the pressure and vent the lines.
• Risk of injury from electric shock: Before reaching into the device or the system, switch off the power supply and secure it against reactivation.
• Breaking hazard: Do not use the solenoid as a lever arm. Hold the device on the body using an open-end wrench and screw into the pipeline.

Manual Override (Optional)

To manually operate the valve, the hand lever must be turned to a vertical position below the solenoid.

INFO

Do not over-rotate the hand lever. When the hand lever is actuated, the valve can no longer be switched electrically.