BURKERT 20088442 (Type 3361) is an electromotive 2-way globe control valve engineered for precise process control tasks under demanding operating conditions. The assembly combines a stainless steel globe valve body with an AG3 electromotive linear actuator that delivers a nominal positioning force of 10,000 N via a ball screw drive. Port connections are configured as welded ends DN 80 (NPS 3) with pipe dimensions of 85.0 x 2.0 mm conforming to DIN 11850-2, DIN 11866 series A, and DIN EN 10357 series A. The valve seat has a nominal diameter of 80 mm, providing a rated flow coefficient of Kvs 100 m³/h (Cv 115.6 gpm) with an equal-percentage 50:1 flow characteristic.

Operating with a positioning dead band of ±0.1% and a linear travel speed of 3 mm/s, the AG3 actuator achieves a typical closing time of 12.0 s. The unit is supplied in normally closed (NC) status and includes an internal SAFEPOS energy-pack emergency storage module that drives the valve to the fail-safe closed position upon supply voltage failure. Fluid control is directed against closing direction (flow below seat), and sealing integrity complies with DIN EN 60534-4 leakage class VI using a PTFE seat seal washer. Operator interface and commissioning are facilitated through a rugged display module with push buttons, a 360° LED illuminated ring for visual status indication, and a service büS interface compatible with the Bürkert Communicator software Type 8920.

Technical Specifications

Specification Parameter	Value / Range
Valve Type	Electromotive 2-way globe control valve (Type 3361)
Article Number	20088442
Actuator Size & Driving Force	AG3 (10,000 N linear electromotor)
Nominal Diameter	DN 80 (NPS 3)
Port Connection Type	Welded ends (tube 85.0 x 2.0 mm)
Connection Standards	DIN 11850-2 / DIN 11866 series A / DIN EN 10357 series A
Valve Seat Diameter	80 mm (3")
Flow Coefficient	Kvs = 100 m³/h (Cv = 115.6 gpm)
Flow Characteristic	Equal percentage, theoretical rangeability 50:1
Operating Pressure Range	0 to 21 bar(g) (12.5 bar(g) for group 1 compressible fluids per 97/23/EC)
Nominal Pressure Class	PN 25 (DIN EN 1333), Class 150 (DIN EN 1759)
Flow Direction	Below seat (against closing direction, 2 → 1)
Seat Leakage Class	Class VI according to DIN EN 60534-4
Medium Temperature Range	-10 °C to +130 °C (PTFE seat seal limit)
Ambient Temperature Range	-25 °C to +65 °C (derated with display / SAFEPOS modules)
Operating Voltage	24 V DC ±10% (maximum residual ripple 10%)
Operating Current	Maximum 5 A (at maximum load including SAFEPOS charging current); +6 A at min. operating temp.
Standby Power Consumption	2 to 5 W
Travel Speed	3 mm/s (AG3 driving force 10,000 N)
Typical Closing Time	12.0 s (AG3 total travel range 8.7 to 12.0 s)
Position Control Dead Band	±0.1%
Duty Cycle	100% continuous
Protection Class (DIN EN 61140)	III
Enclosure Rating	IP65 / IP67 (DIN EN 60529), NEMA 4X
Permissible Fluid Viscosity	Up to 600 mm²/s
Weight	AG3 actuator approx. 16 kg (excluding valve body)
Installation Position	Any, preferably upright with actuator above the valve body

Materials of Construction

All media-wetted components comply with EC Regulation 1935/2004 and FDA regulations. The spindle packing utilizes self-adjusting PTFE V-rings energized by a spring compensation mechanism.

Item	Component	Material
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	PTFE seal washer (soft sealing, leakage Class VI)
7	Control cone	Stainless steel 1.4571 (316Ti)
8	Valve seat	Stainless steel 1.4571 (316Ti)
9	Valve seat O-ring	EPDM or PTFE
10	Valve body	Stainless steel CF3M (cast equivalent to 316L)

Item	Actuator Component (AG3)	Material
1	Display housing / blind cover	Polyphenylene sulfide (PPS)
2	Actuator cover	Polycarbonate (PC)
3, 6	Housing seals	EPDM
4	Actuator housing	Aluminium, powder-coated
5	SAFEPOS energy-pack housing	Polycarbonate (PC)
7	Actuator base	Stainless steel 1.4308

Dimensions and Installation

Actuator AG3 Dimensions (DN 80)

• Standard variant total height (H1): 628 mm
• Fieldbus variant total height (H2, if equipped): 700 mm
• Sealing lift notice: in the fully closed position, the actuator lifts by approximately 2 mm without sealing function.

Welded End Body Dimensions (DN 80)

• Nominal diameter: DN 80 (NPS 3)
• Pipe insertion depth (ES): 26 mm
• Face-to-face length (LS): 230 mm
• Pipe outer diameter (∅ DS): 85.0 mm (Series A)
• Pipe wall thickness (WS): 2.0 mm (Series A)

Installation Recommendation

The valve can be mounted in any orientation. Mounting upright with the actuator positioned vertically above the valve body is recommended to ensure optimal drainage, reduced particulate accumulation in the packing gland, and convenient display visibility.

Electrical Connections and Pin Assignments

Article 20088442 utilizes an analogue control architecture with M12 circular connectors located on the AG3 actuator base. Supply power and control signals are routed through dedicated plugs.

• Connector X1: M12 circular plug, 8-pin, A-coded (input and output signals)
• Connector X4: M12 circular plug, 5-pin, L-coded (operating voltage 24 V DC)
• Connector X3: M12 circular plug, 5-pin, A-coded (büS / CANopen service interface)

X1 Signal Pin Assignment (M12 8-Pin, A-Coded)

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

X4 Power Supply Pin Assignment (M12 5-Pin, L-Coded)

Pin	Assignment	Function
1	Operating voltage +	24 V DC ±10%
2	Not connected	-
3	GND	Power supply ground
4	Not connected	-
FE	Functional earth	Connected directly to valve body and actuator housing

Fluidic Performance and Operating Limits

The DN 80 globe body with seat diameter 80 mm features an equal-percentage characteristic curve calibrated according to DIN EN 60534-2-4 with a rangeability of 50:1.

Flow Curve Values Across Stroke (DN 80 / Seat 80)

Stroke (%)	5%	10%	20%	30%	40%	50%	60%	70%	80%	90%	100% (Kvs)
Kv (m³/h)	2.1	2.6	4.2	7.0	10.5	16.0	25.0	40.0	60.0	83.0	100.0

Pressure and Temperature Operating Limits

• Maximum differential operating pressure: 21 bar(g) for liquid media with PTFE seat seal.
• For compressible media in Group 1 (hazardous gases and vapors per Directive 97/23/EC), the maximum operating pressure is limited to 12.5 bar(g).
• The PTFE soft seat seal provides bubble-tight shut-off (leakage Class VI) within a media temperature envelope of -10 °C to +130 °C. The valve body PN 25 rating derates at elevated temperatures in accordance with DIN EN 12516-1.

Product Architecture and Operation

Integrated Position Controller

The positioning system compares the external command signal (CMD, analogue 0/4 to 20 mA or 0 to 5/10 V) with the internal position feedback (POS) measured by a contactless displacement transducer on the motor spindle. If a control deviation (Xd1) exists, the motor drive adjusts the spindle stroke via the manipulating variable CTRL until the target position is reached.

Display Module and Visual Indicators

• Display Module: Features navigation keys, back button, and multi-view status monitoring for parameter adjustment.
• 360° LED Light Ring: Illuminates, flashes, or alternates colors to signal operating state, end positions, and error conditions.
• Mechanical Position Indicator: Yellow visual pointer located in the transparent inspection window confirms actual valve stroke even when unpowered.

Manual Actuation

1. Electrical Manual Override: Operated directly from the display module push buttons in MANUAL mode.
2. Mechanical Manual Override: Located beneath the pressure compensation element on the AG3 actuator base. Using a 3 mm Allen key, the drive spindle can be manually rotated in the de-energized state. Maximum torque must not exceed 2 Nm.

SAFEPOS Energy-Pack Emergency Module

The plug-in SAFEPOS energy-pack provides fail-safe positioning during a supply power interruption. The internal storage device charges completely in less than 120 seconds during initial energization and retains an operating life up to 10 years depending on operating temperature. Upon power failure, the energy pack drives the actuator to the programmed safety position (factory default: fully closed).

Maintenance, Replacement, and Calibration

Pressure and Voltage Hazard

Before opening or servicing the valve assembly, isolate the pipeline, vent process pressure, completely drain the media, and switch off the 24 V DC supply voltage. Completely discharge the SAFEPOS energy-pack and verify that the 360° LED ring has turned completely off.

Prevent Sealing Damage

During actuator removal or reinstallation, the valve must be driven to at least 1/3 open or fully open position. Unscrewing the actuator while the valve cone is pressed tightly into the seat will shear the PTFE seal washer and damage the cone contour.

Control Cone Replacement

1. Switch operating mode to MANUAL and drive valve to at least 1/3 open.
2. Disconnect electrical power and verify LED ring extinction.
3. Unscrew actuator connection from the body using an open-end wrench on the wrench flats.
4. Support the cylindrical section of the control cone in a prism fixture and drive out the dowel pin using a 5 mm pin punch.
5. Install the replacement control cone, align the spindle bores, insert the dowel pin, and tap flush with a hammer.

Valve Seat Replacement

1. Clamp the valve body firmly in a holding fixture.
2. Engage the dedicated seat replacement tool (Burkert order no. 655563 for DN 80) into the threaded valve seat.
3. Unscrew the worn seat counter-clockwise, clean body internal threads with oil-free compressed air, and inspect the body seating shoulder.
4. Lubricate replacement seat threads with Klüberpaste UH1 96-402, thread into body by hand, and tighten with a torque wrench to 120 ± 5 Nm.

Actuator Assembly Torques

• Actuator body connection (DN 80): 120 ± 5 Nm (89 ± 2 lbf ft)
• Actuator cover fastening screws (T25): 5.0 Nm
• SAFEPOS locking screw (T10): 1.1 Nm

X.TUNE Positioner Calibration

Calibration Requirement

Run the X.TUNE routine whenever the actuator has been remounted, the control cone replaced, or the valve seat changed. Never execute X.TUNE while medium pressure is applied to the pipeline.

• On the display module: Navigate from View 1 to CONFIGURATION → Position controller → MAINTENANCE → CALIBRATION → X.TUNE.
• Select the seat seal material (PTFE) and confirm start.
• The valve executes a self-calibration stroke sequence to store physical end stops and dynamic travel limits. The LED illuminated ring shines orange while X.TUNE is executing.