BURKERT 20079579 (Type 3361) is an electromotive 2-way globe control valve engineered for demanding process automation tasks. The valve assembly pairs an AG2 linear actuator delivering 1300 N nominal positioning force with a stainless steel CF3M globe valve body. The process port is configured as a DN 15 flanged connection conforming to DIN EN 1092-1 PN 25, with a face-to-face dimension of 130 mm per DIN EN 558-1 FTF 1. The drive system utilizes a brushless DC motor and precision ball screw mechanism that shifts the control cone at 6 mm/s, achieving a typical closing time of 3.4 s and a position control dead band of ±0.1%. Fluid flows against the closing direction (flow below seat, 2 → 1) past an 8 mm exchangeable valve seat, providing an equal-percentage flow characteristic with a 50:1 theoretical rangeability, a rated Kvs of 2.1 m³/h (Cv 2.4 gal/min), and Class IV seat leakage according to DIN EN 60534-4.

The valve operates on a 24 V DC power supply and features integrated digital position control, an optical 360° LED status ring, a local display module with operating keys, and a PROFINET industrial Ethernet gateway with an integrated 2-port switch alongside the büS service interface. In the event of an external power loss, an integrated SAFEPOS energy-pack emergency power storage automatically drives the valve to the pre-configured normally closed safety position. The closed exterior housing design complies with IP65/IP67 ingress ratings (NEMA 4X) and holds Ecolab detergent cleaning certification, making the unit suitable for hygienic and chemically demanding wash-down environments.

General Technical Specifications

Technical Parameter	Specification / Value
Valve Type	Type 3361 electromotive 2-way globe control valve
Order Identifier (Ident)	20079579
Nominal Diameter (Port Size)	DN 15 (NPS 1/2")
Port Connection Type	Flange DIN EN 1092-1 PN 25 (face-to-face 130 mm acc. to DIN EN 558-1)
Valve Seat Diameter	8 mm (5/16")
Flow Coefficient Kvs (Water)	2.1 m³/h (Cv: 2.4 gal/min)
Flow Characteristic	Equal percentage 50:1 (acc. to DIN EN 60534-2-4)
Flow Direction	Below seat (flow direction 2 → 1)
Operating Pressure Range	0 to 25 bar(g)
Nominal Pressure Rating	PN 25 (DIN EN 1333) / Class 150 (DIN EN 1759)
Seat Leakage Class	Class IV (DIN EN 60534-4)
Actuator Size and Nominal Force	AG2 (1300 N)
Travel Speed	6 mm/s
Typical Closing Time	3.4 s (3400 ms)
Position Control Dead Band	±0.1%
Safety Position on Power Failure	Normally closed (delivery status), powered by SAFEPOS energy-pack
Operating Voltage	24 V DC ± 10% (maximum residual ripple 10%)
Operating Current	Max. 3 A (at max. load, including 1 A SAFEPOS charging); +2 A at min. temp.
Standby Power Consumption	2 to 5 W
Electrical Protection Class	Class III (DIN EN 61140)
Operating Duty Cycle	100% continuous
Communication Protocols	büS (CAN-based) + PROFINET (integrated fieldbus gateway)
Local User Interface	Display module with operation keys, büS service port, 360° LED ring
Medium Temperature Range	-10 °C to +230 °C
Ambient Temperature Range	-25 °C to +65 °C (without modules; subject to derating)
Fluid Viscosity Limit	Up to 600 mm²/s
Permissible Process Media	Steam, neutral gases, water, alcohols, oils, fuels, hydraulic fluids, salt solutions, organic solvents
Degree of Protection	IP65/IP67 (DIN EN 60529), NEMA 4X
Installation Position	Any orientation; actuator upright orientation recommended
Actuator Weight	Approx. 5.5 kg (AG2 actuator alone; total valve weight depends on body)

Approvals and Standards Compliance

BURKERT 20079579 complies with applicable European harmonized standards and international hygiene specifications:

• EU Directives: CE marked in compliance with applicable EU Declaration of Conformity and directive requirements.
• Food Contact (FDA): All wetted elastomeric and polymeric materials comply with the United States Food and Drug Administration Code of Federal Regulations (21 CFR).
• Food Contact (EC 1935/2004): All wetted components conform to European Regulation (EC) No 1935/2004 per manufacturer declaration.
• Cleaning Agent Compatibility: Certified according to Ecolab test method F&E/P3-E No. 40-1 for resistance to industrial cleaning and disinfecting agents.

Auxiliary Certifications in Series Documentation

The Type 3361 product family includes options for ATEX/IECEx Zone 2/22 (Code PX48), cULus listing (Code PU11: UL 61010-1 and CAN/CSA-C22.2 No. 61010-1), UBA drinking water compliance up to +85 °C (Code PF39), Chinese GB food standards (Code PL10), TA-Luft air quality sealing (Code PM01), and certified oxygen/hydrogen variants. Article 20079579 carries standard IP65/IP67, FDA, EC 1935/2004, and Ecolab conformity.

Materials of Construction

Actuator Material Specification (AG2)

Item	Actuator Component	Material
1	Display housing / blind cover / gateway housing	PPS (standard)
2	Actuator cover	PPS
3	Seal rings	EPDM
4	Actuator housing	Powder-coated die-cast aluminium
6	Seals	EPDM
7	Actuator base	PPS

Valve Body and Internal Trim Materials

Item	Valve Component	Material Specification
1	Spindle	Stainless steel 1.4401 (316) / 1.4404 (316L)
2	Spindle seal	PTFE V-seals (filled) 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 (metal-to-metal sealing)
7	Control cone	Stainless steel 1.4571
8	Valve seat	Stainless steel 1.4571 (screwed-in, exchangeable)
9	O-ring valve seat	EPDM or PTFE
10	Valve body	Cast stainless steel CF3M

Chemical Compatibility Verification

Material resistance for specific aggressive media can be verified using the Bürkert resistApp chemical resistance tool at www.burkert.com.

Dimensions and Installation Geometry

Actuator Height Dimensions (AG2)

Nominal Diameter DN	Nominal Diameter NPS	H1 Standard Height (mm)	H2 Fieldbus Gateway Height (mm)
10	3/8"	417	489
15	1/2"	417	489
20	3/4"	423	495
25	1"	446	518
32	1 1/4"	474	546
40	1 1/2"	479	551
50	2"	485	557

Note on height dimensions: In the closed position without sealing function, the actuator is raised by approximately 2 mm. Article 20079579 includes the fieldbus gateway module, corresponding to height H2 = 489 mm.

Flanged Body Dimensions (DIN EN 1092-1 PN 25)

DN	∅ DF (Flange OD)	LF (Face-to-Face FTF 1)	∅ BF (Bolt Circle)	AF (Flange Thickness)	∅ D (Hole Dia.)	A × α (Bolt Pattern)	∅ MF (Port Bore ID)
10	90 mm	130 mm	60 mm	16 mm	14 mm	4 × 90°	13.6 mm
15	95 mm	130 mm	65 mm	16 mm	14 mm	4 × 90°	18.1 mm
20	105 mm	150 mm	75 mm	18 mm	14 mm	4 × 90°	23.7 mm
25	115 mm	160 mm	85 mm	18 mm	14 mm	4 × 90°	29.7 mm
32	140 mm	180 mm	100 mm	18 mm	18 mm	4 × 90°	38.4 mm
40	150 mm	200 mm	110 mm	18 mm	18 mm	4 × 90°	44.3 mm
50	165 mm	230 mm	125 mm	20 mm	18 mm	4 × 90°	56.3 mm
65	185 mm	290 mm	145 mm	22 mm	18 mm	8 × 45°	66.0 mm
80	200 mm	310 mm	160 mm	24 mm	18 mm	8 × 45°	81.0 mm
100	235 mm	350 mm	190 mm	24 mm	22 mm	8 × 45°	100.0 mm

Electrical Connections and Communication Interfaces

Article 20079579 utilizes M12 industrial circular connectors for electrical supply, digital/analogue signals, and industrial Ethernet fieldbus connection.

M12 Connector Assignment Matrix for AG2 Variants

Connector Identifier	Connector Design	Function in Article 20079579
X1	M12 circular plug, 8-pin, A-coded	Digital and analogue input/output signals (standard)
X2	M12 circular socket, 5-pin, A-coded	Process actual value input (used only on process controller models)
X3	M12 circular plug, 5-pin, A-coded	24 V DC supply voltage and büS / CANopen interface
X7	2 × M12 circular socket, 4-pin, D-coded	PROFINET industrial Ethernet fieldbus (2-port switch)

Pin Assignment Tables

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

Pin Number	Signal Assignment
1	Digital input +
2	GND for digital input and digital outputs
3	Digital output 2 +
4	Digital output 1 +
5	Analogue output -
6	Analogue output +
7	Set-point value / Analogue input -
8	Set-point value / Analogue input +

Connector X3 — Supply Voltage AG2 and büS/CANopen (M12 5-Pin, A-Coded Plug)

Pin Number	Signal Assignment
1	CAN shield / cable shield
2	Operating voltage 24 V DC ± 10%
3	GND / CAN_GND
4	CAN_H
5	CAN_L

Connector X7 — Fieldbus PROFINET (2 × M12 4-Pin, D-Coded Sockets)

Pin Number	Signal Assignment
1	Transmit Data + (TD+)
2	Receive Data + (RD+)
3	Transmit Data - (TD-)
4	Receive Data - (RD-)

Fluidic Characteristics and Flow Data

Type 3361 features an equal-percentage flow characteristic curve in accordance with DIN EN 60534-2-4. Flow is routed under the valve seat (flow direction 2 → 1) to eliminate water hammer and maintain continuous control stability.

Fluidic Performance Data for DN 15 / NPS 1/2" Port Connection

Seat Size (mm)	Actuator Force (N)	Max. Differential Pressure [bar(g)]	Theoretical Rangeability	Kv at 10% Stroke (m³/h)	Kv at 20% Stroke (m³/h)	Kv at 30% Stroke (m³/h)	Kv at 40% Stroke (m³/h)	Kv at 50% Stroke (m³/h)	Kv at 60% Stroke (m³/h)	Kv at 70% Stroke (m³/h)	Kv at 80% Stroke (m³/h)	Kv at 90% Stroke (m³/h)	Kvs at 100% Stroke (m³/h)
3	1300	25 (IV)	20:1	0.005	0.009	0.013	0.019	0.026	0.034	0.044	0.060	0.077	0.1
3	1300	25 (IV)	20:1	0.009	0.015	0.023	0.033	0.046	0.063	0.085	0.11	0.16	0.2
4	1300	25 (IV)	30:1	0.023	0.033	0.049	0.070	0.097	0.14	0.18	0.26	0.35	0.5
6	1300	25 (IV)	50:1	0.007	0.011	0.045	0.085	0.16	0.26	0.41	0.65	1.1	1.25
8	1300	25 (IV)	50:1	0.080	0.11	0.13	0.19	0.27	0.43	0.63	0.95	1.6	2.1
10	1300	25 (IV)	50:1	0.11	0.15	0.19	0.31	0.49	0.75	1.1	1.7	2.5	3.1
15	1300	25 (IV)	50:1	0.17	0.22	0.35	0.52	0.80	1.2	1.8	2.7	3.7	4.3

Article 20079579 features seat size 8 mm with stainless steel metallic seating, yielding Kvs = 2.1 m³/h and Class IV seat leakage up to 25 bar(g).

Operating Limits and Temperature Derating

Process pressure is limited by both maximum actuator operating pressure and standard pressure-temperature ratings. Under DIN EN 12516-1 PN 25, the pressure envelope is bounded by the saturated steam curve for water up to the maximum medium temperature of +230 °C.

Seat Seal Performance Comparison

Tight Sealing Required	Seat Seal Material	Leakage Class (DIN EN 60534-4)	Permissible Medium Temperature	Application Note
No (additional shut-off valve recommended)	Stainless steel 1.4571	Class III / IV	-40 °C to +230 °C	Impervious to harsh thermal/mechanical conditions; hardened trim available for cavitation or abrasive media. (Supplied with 20079579)
Yes (soft sealing)	PTFE	Class VI	-40 °C to +130 °C (recommended ≤ +130 °C)	Provides bubble-tight shut-off without upstream isolation valve.
Yes (soft sealing)	PEEK	Class VI	-10 °C to +230 °C (recommended > +130 °C)	High-temperature polymer soft seal for tight shut-off up to +230 °C.

Ambient and Medium Temperature Derating (AG2 Actuator)

The permissible ambient temperature depends directly on the process fluid temperature. For Article 20079579, which combines the AG2 actuator with the SAFEPOS energy-pack and fieldbus gateway module, Curve 3 applies:

• Curve 1: Basic devices without expansion modules.
• Curve 2: Devices fitted with display module only.
• Curve 3: Devices fitted with SAFEPOS energy-pack or fieldbus gateway, with or without display module.

At maximum fluid temperatures up to +230 °C, the permissible ambient temperature must be derated according to Curve 3 to prevent thermal overload of the actuator electronics.

Actuator Design and Functional Features

Linear Drive Mechanism

The AG2 actuator incorporates an electronically commutated brushless DC motor coupled to a reduction gear and a precision recirculating ball screw spindle system. This mechanical arrangement converts rotational motion into linear thrust with zero backlash, holding the control cone securely in position even under maximum media line pressure without consuming continuous holding current.

SAFEPOS Energy-Pack Emergency Positioning

Article 20079579 includes the integrated SAFEPOS energy-pack module:

• Functional Principle: Upon total loss of 24 V DC main supply, the internal energy storage immediately supplies the motor drive, moving the valve to a defined safety position (normally closed in delivery status).
• Charging Time: The energy pack reaches full charge readiness within a maximum of 120 seconds after power-up.
• Lifespan: Service life is rated up to 10 years, depending on operating and temperature conditions.
• Self-Monitoring: The actuator actively monitors the energy-pack capacitance and displays an advance warning when replacement is required.

Manual Actuation Methods

1. Electrical Manual Operation: Performed directly via the display module navigation buttons, or using the internal OPEN/CLOSE buttons beneath the top cover.
2. Mechanical Manual Override: When de-energized, the valve can be actuated mechanically using a 3 mm Allen key inserted into the manual override mechanism located beneath the display/gateway module. Maximum applied torque must not exceed 2 Nm.

Position Indication and Diagnostics

• 360° LED Light Ring: Integrated into the display housing perimeter, providing clear multi-color status signaling (operation, position reached, maintenance warnings, error states).
• Mechanical Indicator: A yellow indicator visible through a clear sight glass shows the exact physical stem position at all times, including during power outages.

Integrated Position Controller

The integrated positioner compares the target position value (CMD) received via PROFINET or analogue input with the actual position value (POS) measured by an internal contact-free displacement sensor. When a control deviation (Xd1) exists, the microprocessor modulates the motor drive (CTRL) to adjust the spindle position until deviation falls within the ±0.1% dead band.

Diagnostic algorithms continually track stem travel cycles, operating hours, temperature profiles, and packing gland integrity, issuing preventive maintenance notifications before field failure occurs.

Installation, Maintenance, and Calibration

High Pressure and Electrical Shock Hazard

Before dismantling the valve from the piping system or opening the actuator housing, depressurize and vent all process lines, drain residual medium, switch off the 24 V DC supply, and completely discharge the SAFEPOS energy-pack. Wait until the 360° LED ring is entirely extinguished.

Fastening Torques for Maintenance and Body Assembly

Assembly Point / Threaded Joint	Tool Size / Thread	Specified Tightening Torque
Body Connection (DN 10/15)	Open-end wrench on body connection	45 ± 3 Nm (33 ± 2 lbf ft)
Body Connection (DN 20)	Open-end wrench on body connection	50 ± 3 Nm (37 ± 2 lbf ft)
Body Connection (DN 25)	Open-end wrench on body connection	60 ± 3 Nm (44 ± 2 lbf ft)
Valve Seat Installation (Seat Size 3–15, DN 10/15)	Installation tool 652604	20 + 3 Nm
Valve Seat Installation (Seat Size 20, DN 20)	Installation tool 652605	28 + 3 Nm
Valve Seat Installation (Seat Size 25, DN 25)	Installation tool 652606	40 + 5 Nm
Lower Spindle Guide (ø10 mm Spindle, DN 10/15)	Modified socket wrench 683220 (SW19)	15 Nm
Lower Spindle Guide (ø10 mm Spindle, DN 20)	Modified socket wrench 683222 (SW21)	25 Nm
Actuator Base Screws (4× screws to housing)	Hex socket head	5 Nm (tighten crosswise)
Actuator Cover Fastening Screws (4× screws)	Hexalobular internal T25	5 Nm (tighten crosswise)
Fieldbus Gateway Fastening Screw	Hex socket head 3 mm	1.1 Nm
SAFEPOS Energy-Pack Locking Screw	Hexalobular internal T10	1.1 Nm
Mechanical Manual Override	Hex key 3 mm	Max. 2 Nm (do not exceed)

Critical Disassembly Requirement

To prevent permanent mechanical damage to the valve body seat and the control cone contour, the valve must be positioned at least 1/3 open before unscrewing the actuator from the valve body.

Running the X.TUNE Calibration Routine

After replacing the valve seat, control cone, spindle seal packing, or after reinstalling the actuator onto the valve body, the automatic X.TUNE function must be executed to calibrate the position control system to the mechanical stroke limits:

1. Ensure that the valve is completely depressurized and no process medium is present.
2. Enter MANUAL operating mode via the display context menu or by setting internal DIP switch 4 to ON.
3. Trigger X.TUNE via the display menu (CONFIGURATION → Position Controller → MAINTENANCE → CALIBRATION → X.TUNE) or by pressing and holding both the OPEN and CLOSE buttons simultaneously for 5 seconds.
4. During calibration, the 360° LED ring illuminates orange. Once completed, the ring returns to the standard operating display state.

Potential X.TUNE Error Messages

• There are device errors: An internal hardware error is preventing the calibration run.
• Time limit exceeded: The calibration sequence could not complete within the allotted time interval.
• Motor current is too high: Mechanical binding or excessive friction detected during stroke traversal.
• Lower end position of the valve is not detected: The displacement sensor failed to detect the closed seat boundary.

Accessories and Ordering Identifiers

Accessory Description	Article Identifier
SAFEPOS energy-pack replacement module (for AG2 actuator)	285834
Control cone replacement set (Type 3361, DN 10/15, Seat Size 8, Steel/steel)	149 935
Valve seat replacement set (Type 3361, DN 10/15, Seat Size 8, with graphite seal)	262 147
Packing gland seal kit (ø10 mm spindle, DN 15/20)	285 685
Stainless steel spindle guide for packing gland (DN 15 body, ø10 mm spindle)	246 577
Valve seat installation tool (for Type 3361, DN 15 body)	652 604
Modified socket wrench for packing gland (SW19, ø10 mm spindle, DN 15)	683 220
Parameter transfer SIM card	291 773
Holding device for line connection clamping (DN 15 to DN 20)	693 770
M12 circular socket with 5 m cable, 4-pin, A-coded (for X3 power AG2)	918 038
M12 circular socket with 2 m cable, 8-pin, A-coded (for X1 I/O signals)	919 061
M12 circular plug to straight M12 plug cable, 4-pin, D-coded, 5 m (for X7 PROFINET)	775 043
M12 circular plug to RJ45 plug cable, 4-pin, D-coded, 5 m (for X7 PROFINET)	775 053
USB-büS interface set 1 (Type 8923 with power supply, stick, terminating resistor, Y-splitter)	772 426
USB-büS interface set 2 (Type 8923 stick, terminating resistor, Y-splitter)	772 551
büS adapter cable (M12 to micro USB büS service interface, length 0.3 m)	774 931
Bürkert Communicator configuration software	Type 8920