Burkert Type 6281 is a servo-assisted diaphragm valve designed for controlling, shutting off, and dosing neutral media with a viscosity of up to 21 mm²/s. A minimum differential pressure of 0.2 bar is always required for the valve to function. The standard brass body meets European drinking water requirements, and dezincification-resistant brass or stainless steel variants are available for specific market needs.

To reduce electrical power consumption during operation, coils with integrated Kick-and-Drop (KD) electronics featuring double coil technology are available. The valve features a vibration-resistant, centrally screwed coil system and a damped design for quiet closing.

General Technical Data

Feature	Specification
Orifice	DN 10 to DN 50
Body Material	Brass acc. to DIN EN 50930-6, Stainless steel 1.4408 (CF8M)
Seal Material	NBR, EPDM, FKM
Duty Cycle	100% continuous operation
Switching Time	Opening: 0.1...1.5 s, Closing: 0.2...4 s
Voltage Tolerance	±10%
Degree of Protection	IP65 in accordance with DIN EN 60529/IEC 60529 with cable plug

Medium Temperature Limits

• With NBR: -10 °C to +80 °C
• With EPDM: -30 °C to +90 °C (with epoxy coil to +100 °C)
• With FKM: 0 °C to +90 °C (with epoxy coil to +120 °C)

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

Special Instructions for Circuit Function B

For valves with circuit function B (NO) featuring exhaust port G1/8 on the solenoid (CF05/MX62), the valve is open when there is no power. The medium also flows out via the exhaust port on the solenoid. These are primarily suitable for compressor relief.

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 or stainless steel 1.4408 (CF8M)

Dimensions (Standard Threaded Variant)

Dimensions in mm. The dimensions F1 and G1 apply to G thread.

DN	A	B	C	D	E	G1	L	SW
10	83.1	94.1	32	44	22	G 1/4, G 3/8	50	22
13	91.1	104.6	42	54.5	27.25	G 3/8, G 1/2	58	27
20	99.6	115.6	60	74	37	G 3/4	80	32
25	106.6	127.1	70	85	46	G 1	95	41
40	120.1	145.1	99	114	61	G 1 1/4, G 1 1/2	126	50
50	119.9	154.9	115	132	82	G 2	164	70

Type Label Identification

The type label includes: (1) Type, (2) Circuit function, (3) Orifice, (4) Sealing material, (5) Body material, (6) PN, (7) Connection type, (8) Power, (9) Frequency, (10) Voltage, (11) Manufacture code, and (12) Article number.

Safety and Installation

Risk of injury from high pressure and electric shock

• Before loosening lines or valves, switch off the pressure and vent the lines.
• Before reaching into the device or the system, switch off the power supply and secure it against reactivation.

Installation Precautions

• 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.
• Observe the flow direction: the arrow on the body indicates the flow direction.
• Install a dirt trap upstream of the valve inlet (≤ 500 µm).

Manual Override (Optional)

To manually operate the valve (code HA15/HA17), the hand lever must be turned to a vertical position below the solenoid. Do not over-rotate the hand lever. When the hand lever is actuated, the valve can no longer be switched electrically.