BURKERT 320767 (Type 3361) is an electromotive 2-way globe control valve with an AG2 linear actuator (nominal force 1,300 N), engineered for continuous control under demanding operating conditions. Article 320767 features a DN 20 port connection according to DIN 32676 series B for ISO 4200 pipe (26.9 x 1.6 mm, clamp flange diameter 50.5 mm) and a precision-cast stainless steel CF3M valve body. Fluid flows against the closing direction (flow below seat 2 → 1) with an equal-percentage flow characteristic and a 50:1 theoretical rangeability. The valve is driven by a 24 V DC brushless motor via a ball screw, delivering a positioning speed of 6 mm/s and a typical closing time of 3.3 seconds.

Sealing at the seat is stainless steel to stainless steel (1.4571) with leakage Class IV according to DIN EN 60534-4, operating across a medium temperature range from -10 °C to +185 °C and pressures from 0.00 to 25.00 bar(g). The unit includes an integrated position controller with a dead band of ±0.1%, an impact-resistant display module with operating keys, an optical 360° LED status ring, a mechanical position indicator, and a Service-büS interface for parameterization via Bürkert Communicator software.

Technical Data

Specification Parameter	Value for Article 320767
Product Type	Electromotive 2-way globe control valve
Burkert Type Family	3361
Actuator Size / Nominal Force	AG2 / 1,300 N
Nominal Diameter (Pipe Connection)	DN 20 (NPS 3/4")
Port Connection Type / Standard	Clamp connection / DIN 32676 series B (ISO 4200 pipe: 26.9 x 1.6 mm, Cl: 50.5 mm)
Flow Direction	Against closing direction (below seat, 2 → 1)
Nominal Pressure Rating	PN 25 (DIN EN 1333), Class 150 (DIN EN 1759)
Operating Pressure Range	0.00 to 25.00 bar(g)
Flow Coefficient (Kvs)	7.1 m³/h (water at +25 °C, DIN EN 60534-2-4)
Flow Coefficient (Cv)	8.3 gpm
Seat Diameter	20 mm (seat size 20)
Theoretical Rangeability	50:1
Flow Characteristic	Equal percentage
Seat Leakage Class	Class IV (DIN EN 60534-4)
Travel Speed	6 mm/s (at 1,300 N actuator force)
Typical Closing Time	3.3 s
Dead Band of Position Control	±0.1%
Supply Voltage	24 V DC ± 10% (max. residual ripple 10%)
Maximum Operating Current	3 A (AG2 at maximum load)
Standby Power Consumption	2 to 5 W
Duty Cycle	100% continuous
Protection Class	Class III (DIN EN 61140)
Ingress Protection Rating	IP65 / IP67 (DIN EN 60529), NEMA 4X
Medium Temperature Range	-10 °C to +185 °C
Ambient Temperature Range	-25 °C to +65 °C (see derating limits)
Maximum Fluid Viscosity	Up to 600 mm²/s
Fail-Safe Position (Power Loss)	Blocking of static position, no electrical energy storage
Actuator Weight	Up to 5.5 kg (AG2 actuator alone)
Food Contact Compliance	(EC) 1935/2004 according to manufacturer declaration
Detergent Resistance	Ecolab certified (F&E/P3-E No. 40-1)

Materials of Construction

Item	Component	Material
1	Display housing / blind cover	PPS (standard)
2	Actuator cover	PPS
3	Seal	EPDM
4	Actuator housing	Powder-coated aluminium
6	Seal	EPDM
7	Actuator base	PPS
—	Spindle	Stainless steel 1.4401 (316) / 1.4404 (316L)
—	Spindle seal	PTFE V-seals (filled) with spring compensation
—	Spindle guide	Stainless steel 1.4404 (316L)
—	Packing gland tube	Stainless steel 1.4401 (316)
—	Valve body seal	Graphite or PTFE
—	Valve seat seal	Stainless steel 1.4571
—	Control cone	Stainless steel 1.4571
—	Valve seat	Stainless steel 1.4571
—	O-ring valve seat	EPDM or PTFE
—	Valve body	Stainless steel CF3M

Fluidic Performance and Sizing

Type 3361 globe valves operate with fluid entering beneath the valve seat (flow direction 2 → 1). This configuration prevents pressure hammer during closing operations and supports high positioning stability across varied inlet pressures.

Flow Data for DN 20 (NPS 3/4") at 1,300 N Actuator Force

Port Connection DN (NPS)	Seat Size	Actuator Force [N]	Max Operating Pressure [bar(g)]	Leakage Class	Theoretical Rangeability	Kv Value at Stroke: 5%	10%	20%	30%	40%	50%	60%	70%	80%	90%	100% (Kvs)
DN 20 (3/4")	10	1,300	25	IV	50:1	—	0.12	0.16	0.20	0.33	0.52	0.77	1.2	1.8	2.6	3.2 m³/h
DN 20 (3/4")	15	1,300	25	IV	50:1	0.14	0.17	0.22	0.35	0.52	0.80	1.2	1.8	2.9	4.0	5.2 m³/h
DN 20 (3/4")	20	1,300	25	IV	50:1	0.20	0.25	0.30	0.45	0.70	1.1	1.6	2.4	3.5	5.2	7.1 m³/h

INFO

Article 320767 is factory-fitted with seat size 20, providing a Kvs rating of 7.1 m³/h (Cv 8.3 gpm). The screwed-in seat ring design allows seat exchange to reduce orifice sizing if lower flow capacity or altered control spans are required on existing process lines.

Dimensions

Overall and Installation Dimensions for Article 320767

Dimension Parameter	Dimension [mm]	Description
H1	423 mm	Total actuator height (in closed position, raised approx. 2 mm without sealing function)
LC	136 mm	Face-to-face body length between clamp faces (DIN 32676 series B)
∅ D2 C	26.9 mm	Pipe outer diameter (DIN EN ISO 1127 / ISO 4200)
∅ D1 C	50.5 mm	Clamp flange outer diameter (DIN 32676 series B)
SC	1.6 mm	Pipe wall thickness

Electrical Connections and Interfaces

Article 320767 is configured with an analogue control interface utilizing M12 circular connectors on the AG2 actuator base.

Plug-in Connector Overview for AG2 Analogue Configuration

Connector Designation	Type and Coding	Function
X1	M12 circular plug, 8-pin, A-coded	Input and output signals (analogue setpoint, binary input, analogue feedback, binary outputs)
X3	M12 circular plug, 5-pin, A-coded	Operating voltage 24 V DC and büS/CANopen communication

Pin Assignment X1 — Input and Output Signals (M12 8-Pin, A-Coded)

Pin Number	Assignment	Technical Characteristics
1	Digital input +	0 to 5 V = log "0", 10 to 30 V = log "1"
2	GND	Common reference for digital input and digital outputs
3	Digital output 2 +	PNP transistor output, max. current limitation 100 mA
4	Digital output 1 +	PNP transistor output, max. current limitation 100 mA
5	Analogue output -	Galvanically isolated feedback ground
6	Analogue output +	0/4 to 20 mA (load 0 to 800 Ω) or 0 to 5/10 V (max. 10 mA)
7	Setpoint / Analogue input -	Galvanically isolated input ground
8	Setpoint / Analogue input +	0/4 to 20 mA (input resistance 70 Ω) or 0 to 5/10 V (input resistance 22 kΩ)

Pin Assignment X3 — Power Supply and büS (M12 5-Pin, A-Coded)

Pin Number	Assignment	Details
1	CAN Shield / shield	Cable shield connection
2	Operating voltage +	24 V DC ± 10% (max. ripple 10%)
3	GND / CAN_GND	Power supply ground and CAN reference
4	CAN_H	Bürkert system bus / CANopen dominant high line
5	CAN_L	Bürkert system bus / CANopen dominant low line

Operation and Device Functions

Integrated Position Controller

The internal microprocessor monitors the physical stroke through an integrated contactless linear displacement transducer (POS). The positioner compares the measured actual position with the setpoint value (CMD) received from the analogue input or digital bus. Any system deviation (Xd1) triggers the motor control electronics (CTRL), driving the brushless motor and ball screw to reposition the control cone until deviation is nullified within the ±0.1% dead band.

Local Display and Manual Operation

• Display Module: Equipped with operation keys, allowing menu navigation, parameter changes, diagnostic readout, and manual stroke positioning.
• Optical 360° LED Ring: Indicates operating states, valve travel direction, and diagnostic warnings via color-coded illumination.
• Mechanical Position Indicator: A yellow indicator visible through the transparent window displays valve position independently of electrical power.
• Electrical Manual Override: Pushbuttons located on the display module allow electrical stroke driving in MANUAL mode.
• Mechanical Manual Override: An internal mechanical coupling operated via an Allen key (3 mm width across flats) permits manual stroke movement when de-energized. Maximum torque is strictly 2 Nm.
• Power Loss Behavior: Article 320767 is supplied without an internal SAFEPOS energy pack. In the event of power supply interruption, the valve spindle stops and remains blocked in its static position.

Operating Limits and Temperature Derating

Permissible ambient temperature depends directly on the process fluid temperature. For AG2 actuators equipped with a display module, operating boundaries follow Curve 2 of the temperature limits chart:

• At a medium temperature of +130 °C, the maximum ambient temperature is +65 °C.
• At a maximum medium temperature of +185 °C, the ambient temperature must not exceed +55 °C.
• Minimum allowable medium temperature is -10 °C; minimum ambient operating temperature is -25 °C.

Installation and Maintenance Instructions

Installation Position

The valve can be installed in any orientation. An upright vertical actuator orientation is recommended to reduce particulate deposition inside the packing gland.

Maintenance Safety Precautions

Depressurize and completely drain process lines before disassembling the actuator from the valve body. Ensure power is switched off. Do not actuate the mechanical manual override while power is connected to prevent drive mechanism damage.

Required Tightening Torques

Mechanical Connection	Component Size	Tightening Torque
Valve body to body connection	DN 20 (NPS 3/4")	50 ± 3 Nm
Valve seat ring	Seat size 20 (DN 20 body)	28 + 3 Nm
Spindle guide (packing gland)	Spindle ∅ 10 mm (DN 20 body)	25 Nm
Actuator base to housing screws	AG2	5 Nm
Mechanical manual override	3 mm Allen socket	Max. 2 Nm

X.TUNE Calibration Procedure

Whenever the valve body is replaced, the actuator is remounted, or seat trim components are exchanged, run the automatic X.TUNE routine to calibrate end positions:

1. Ensure that no process line pressure is applied to the valve.
2. Switch operating mode to MANUAL via the display menu or communication software.
3. Navigate to MAINTENANCE → CALIBRATION → X.TUNE on the display, or hold down the OPEN and CLOSE internal buttons simultaneously for 5 seconds.
4. Confirm the seat sealing material (stainless steel) when prompted. The LED ring lights up orange during calibration and returns to normal status upon completion.