BURKERT 377810 (Type 3361) is an electromotive 2-way globe control valve engineered for precision fluid regulation in continuous process applications. Combining a brushless DC linear actuator with a precision ball screw drive, the unit positions the control cone with a positioning speed of 6 mm/s and a dead band of ±0.1%, ensuring rapid response without pressure-induced position deviation.

Specific article configuration 377810 integrates a DIN EN 1092-1 DN 25 flanged body in cast stainless steel CF3M, paired with a 20 mm (3/4") seat orifice and an equal percentage 50:1 control cone. Actuation is delivered by an AG2 size linear drive exerting 1300 N nominal thrust at 24 V DC. Wetted sealing relies on an all-metal stainless steel 1.4571 seat seal delivering Class IV shut-off tightness, backed by spring-compensated PTFE V-ring stem packings.

Technical Data Summary

Parameter	Technical Specification (Article 377810)
Product Type	Electromotive 2-way globe control valve
Valve Construction	Type 3361, flow-optimised globe design
Nominal Diameter	DN 25 (1")
Port Connection	Flange DIN EN 1092-1 (FTF 1 per DIN EN 558-1)
Pressure Ratings	PN 25 (DIN EN 1333), Class 150 (DIN EN 1759)
Operating Pressure Range	0 to 25 bar(g)
Orifice / Seat Size	20 mm (3/4")
Full Stroke Capacity (Kvs)	7.2 m³/h (Cv 8.4 gpm)
Flow Characteristic	Equal percentage, theoretical rangeability 50:1
Flow Direction	Below seat (against closing direction, 2 → 1)
Seat Seal Material	Stainless steel 1.4571 (metallic seal)
Seat Leakage Class	Class IV (DIN EN 60534-4)
Medium Temperature Range	-40 °C to +185 °C
Ambient Temperature Range	-25 °C to +65 °C
Actuator Variant	AG2 (actuator size 2, 1300 N nominal thrust)
Positioning Speed / Closing Time	6 mm/s / typical 3.3 s (range 3.3 to 6.6 s)
Power Supply	24 V DC ±10% (maximum ripple 10%)
Current Consumption	Max. 3 A at maximum load; standby 2 to 5 W
Power Failure Safety Setting	Blocked in static position (without energy storage)
Control Signals	1 analogue input, 1 digital input, 1 analogue output, 2 digital outputs
User Interface	Blind cover with internal push buttons and 4 DIP switches
Ingress Protection	IP65 / IP67 (DIN EN 60529), NEMA 4X

Construction Materials

Actuator and valve body components feature an enclosed, smooth-surface construction designed for resistance to weather, mechanical vibration, and cleaning detergents in accordance with Ecolab testing procedure F&E/P3-E No. 40-1.

Actuator Assembly (AG2)

Item	Component	Material
1	Blind cover / housing top	Polyphenylene sulphide (PPS)
2	Actuator cover	Polyphenylene sulphide (PPS)
3	Static seal	Ethylene propylene diene monomer (EPDM)
4	Actuator housing	Powder-coated aluminium
6	Housing seal	Ethylene propylene diene monomer (EPDM)
7	Actuator base	Polyphenylene sulphide (PPS)

Valve Body & Wetted Components

Item	Component	Material
1	Valve spindle	Stainless steel 1.4401 (316) / 1.4404 (316L)
2	Spindle seal pack	Filled PTFE V-rings with spring compensation
3	Spindle guide	Stainless steel 1.4404 (316L)
4	Packing gland tube	Stainless steel 1.4401 (316)
5	Valve body seal	Graphite (or PTFE)
6	Seat seal	Stainless steel 1.4571 (metallic seat contact)
7	Control cone	Stainless steel 1.4571
8	Valve seat	Stainless steel 1.4571 (threaded exchangeable design)
9	Seat O-ring	EPDM or PTFE
10	Valve body	Cast stainless steel CF3M

Dimensions & Flange Specifications

Body geometry complies with DIN EN 1092-1 PN 25 face-to-face dimensions FTF 1 according to DIN EN 558-1.

Dimension Parameter	Symbol	Nominal Value (DN 25)
Face-to-face length	LF	160 mm
Flange outer diameter	∅ DF	115 mm
Bolt circle diameter	∅ BF	85 mm
Flange thickness	AF	18 mm
Bolt hole diameter	∅ D	14 mm
Bolt holes quantity & angle	A × α	4 × 90°
Raised face / internal bore	∅ MF	29.7 mm
Actuator height (standard variant)	H1	446 mm
Closed position clearance allowance	—	Additional approx. 2 mm rise

Fluidic Characteristics & Flow Curve

Flow passes beneath the valve seat (direction 2 → 1). The 20 mm seat orifice achieves a theoretical rangeability of 50:1 with equal percentage profiling according to DIN EN 60534-2-4.

Stroke Flow Capacities (DN 25 with Seat Size 20)

Stroke Position	Kv Value [m³/h]
5%	0.20
10%	0.25
20%	0.31
30%	0.47
40%	0.70
50%	1.10
60%	1.60
70%	2.50
80%	3.80
90%	5.40
100% (Kvs)	7.20

Leakage Tightness

Metallic sealing on stainless steel 1.4571 provides Class IV shut-off tightness (permissible leakage ≤ 0.01% of nominal flow rate). Metallic seats maintain continuous operation across thermal cycling without seat deformation.

Electrical Control & Interface Configuration

Article 377810 features analogue setpoint control and status feedback via an integrated terminal arrangement/circular connector layout and internal configuration switches.

Control Signal Specifications

Signal Function	Electrical Parameters
Analogue Setpoint Input	0/4 to 20 mA (input resistance 70 Ω) or 0 to 5/10 V (resistance 22 kΩ); galvanically isolated
Analogue Actual Output	0/4 to 20 mA (load 0 to 800 Ω) or 0 to 5/10 V (max. load current 10 mA)
Digital Control Input	0 to 5 V = logical "0", 10 to 30 V = logical "1" (invertible)
Digital Outputs (2 channels)	Transistor output PNP, current limited to 100 mA
Operating Voltage	24 V DC ±10%, max. 3 A peak current during movement
Service Communication	büS service interface accessed via USB-büS interface set for Bürkert Communicator software

Operation & Manual Override

Control operations and local commissioning take place beneath the bayonet blind cover on the actuator top:

• Operating State Switch: DIP switch 4 configures operational mode. Setting DIP 4 downward engages AUTOMATIC mode; shifting DIP 4 upward engages MANUAL mode.
• Electrical Manual Actuation: Under the blind cover, dedicated OPEN and CLOSE push buttons actuate the motor drive directly in MANUAL mode.
• 360° LED Status Indicator: The top-mounted illuminated ring provides real-time diagnostic status, end-position notification, and error signaling.
• Mechanical Position Indicator: A yellow indicator spindle visible through the transparent window shows physical valve stroke position independently of electrical power.

Mechanical Manual Override Restrictions

Mechanical manual actuation must only be conducted in a fully de-energised state. Insert a 3 mm Allen key into the manual override mechanism located beneath the blind cover. Rotate counter-clockwise to open and clockwise to close. Never exceed the maximum torque limit of 2 Nm.

Calibration & Maintenance Procedures

Running X.TUNE Calibration

The X.TUNE routine aligns internal position sensor measurements with physical mechanical stroke end stops. Calibration is necessary upon initial installation, actuator replacement, or valve seat servicing.

1. Ensure the valve body is completely depressurised and drained.
2. Remove the blind cover by turning counter-clockwise.
3. Press and hold the OPEN and CLOSE push buttons simultaneously for 5 seconds.
4. The LED light ring illuminates orange throughout the active calibration sequence.
5. Upon completion, the LED ring returns to standard operational indication.

Pressure Hazard During Calibration

Never execute X.TUNE under line pressure. Running calibration while media pressure is applied causes severe controller misadjustment and uncalibrated stroke tracking.

Service Tightening Torques

Fastener / Connection Location	Tool / Interface	Tightening Torque
Body connection (Actuator to DN 25 body)	Open-end wrench on body flats	60 ± 3 Nm
Replaceable valve seat (Seat size 20 mm)	Installation tool (Ref. 652605)	28 + 3 Nm
Spindle guide (14 mm spindle, DN 25)	Modified socket wrench SW21	25 Nm
Actuator base screws (AG2 housing)	Hexalobular / Allen key	5 Nm
Actuator cover screws	Hexalobular internal key T25	5 Nm