BURKERT 20086946 (Type 3321) is an electromotive 2/2-way globe shut-off valve designed for demanding process isolation under demanding industrial conditions. Configured with a G 3" internal threaded connection (DN 80 seat size) and an AG3 linear electromotive actuator delivering 10,000 N positioning force, this valve executes rapid flow isolation with a typical closing time of 8.7 seconds at 3 mm/s travel speed. Flow travels below the valve seat (port direction 2 → 1), providing a flow coefficient $K_v$ of 110 m³/h ($C_v$ 127.2 gpm). The wetted construction pairs a cast stainless steel CF3M valve body with a 1.4571 stainless steel seat, 1.4571 swivel plate, PEEK seal washer, and spring-compensated PTFE V-ring spindle packing. Operating pressure spans 0 to 17 bar(g) with medium temperatures from -10 °C to +185 °C. The wetted assembly meets EC Regulation 1935/2004 for food contact.

Technical Specifications

Parameter	Specification
Valve Type	2/2-way electromotive globe on/off valve
Order Code / Article Number	20086946
Type Series	3321
Nominal Diameter / Seat Size	DN 80 (3"), 80 mm seat diameter
Process Connection	G 3" internal thread (DIN ISO 228-1)
Flow Direction	Below seat (direction 2 → 1)
Flow Rate Water ($K_v$)	110 m³/h (DIN EN 60534-2-4)
Flow Rate Water ($C_v$)	127.2 gpm
Operating Pressure Range	0...17 bar(g)
Nominal Pressure	PN 25 (DIN EN 1333), Class 150 (DIN EN 1759)
Seat Leakage	Leakage rate A (DIN EN 12266-1, test medium air)
Medium Temperature	-10 °C...+185 °C
Ambient Temperature	-25 °C...+65 °C (without additional fieldbus module)
Actuator Size / Driving Force	AG3 (10,000 N linear force)
Typical Closing Time	8.7 s
Travel Speed	3 mm/s
Supply Voltage	24 V DC ± 10 % (maximum ripple 10 %)
Operating Current	Max. 5 A at maximum load (additionally 6 A at minimum operating temperature)
Standby Power Consumption	2...4 W
Duty Cycle	100 % continuous
Electrical Protection Class	Class III (DIN EN 61140)
Ingress Protection	IP65 / IP67 (DIN EN 60529), NEMA 4X
Control Mode	Binary (0...5 V = log '0', 10...30 V = log '1')
Digital Inputs / Outputs	1 digital input, 2 digital outputs (current limit 100 mA)
Service Interface	büS service interface (micro-USB connection)
User Interface	Blind cover with internal push buttons and 4 DIP switches (no display)
Power Loss Reaction	Blocked in last static position (no energy storage module installed)
Medium Viscosity	Up to 600 mm²/s
Food Conformity	EC Regulation 1935/2004 compliant (manufacturer declaration)

Materials of Construction

Actuator housing components and process-wetted valve internals are manufactured from high-grade metals and engineering polymers engineered for chemical resistance and external washdown.

Actuator Materials (AG3 Variant)

Item	Component	Material
1	Blind cover / gateway housing	PPS (standard), stainless steel 1.4301 (ATEX/IECEx optional)
2	Actuator cover	Polycarbonate (PC)
3	Seal	EPDM
4	Actuator housing	Powder-coated aluminium
5	Energy storage housing (when fitted)	Polycarbonate (PC)
6	Seal	EPDM
7	Actuator base	Stainless steel 1.4308

Valve Body and Internal Trim Materials

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	PEEK or stainless steel 1.4404 (316L)
4	Packing gland tube	Stainless steel 1.4401 (316)
5	Valve body seal	Graphite or PTFE
6	Swivel plate	Stainless steel 1.4571
7	Valve seat seal	PEEK seal washer (PTFE optional in lower temp ranges)
8	Valve seat	Stainless steel 1.4571
9	O-ring valve seat	EPDM or PTFE
10	Valve body	Stainless steel CF3M

Chemical Resistance Assessment

Material compatibility for aggressive process fluids can be validated through the Bürkert resistApp chemical resistance chart available on the manufacturer website.

Dimensions and Installation

Actuator height and body face-to-face dimensions govern mechanical pipe layout. For actuator size AG3 mounted on a DN 80 port connection, the standard total height H1 (without optional fieldbus gateway module) is 628 mm. When an optional fieldbus gateway is mounted, total height H2 increases to 700 mm. In the closed position without sealing load, the actuator is raised by approximately 2 mm.

Threaded Body Dimensions (DIN ISO 228-1, ASME B1.20.1, ISO 7-1)

DN	NPS	G Thread Depth E [mm]	NPT Depth E [mm]	RC Depth E [mm]	Body Length LM [mm]	Wrench Flat AF [mm]
10	3/8	12	10.3	10.1	65	27
15	1/2	14	13.7	13.2	65	27
20	3/4	16	14	14.5	75	34
25	1	18	16.8	16.8	90	41
32	1 1/4	20	17.3	19.1	110	50
40	1 1/2	22	17.3	19.1	120	55
50	2	24	17.6	23.4	150	70
65	2 1/2	26	23.7	26.7	185	85
80	3	28	30.5	29.8	205	100
100	4	32	33	35.8	240	125

For 20086946 with G 3" connection (DN 80), body face-to-face length LM is 205 mm, thread depth E is 28 mm, and width across wrench flats AF is 100 mm.

Electrical Connections and Control Interfaces

Electrical connection of the AG3 actuator variant is accomplished via round multipole M12 circular connectors located on the side of the actuator base alongside a separate functional earth terminal.

AG3 Connector Allocation

• X1 Connector: M12 circular plug, 8-pin, A-coded. Used for digital input and output control signals.
• X4 Connector: M12 circular plug, 5-pin, L-coded. Dedicated power supply connection for the AG3 electromotive drive.
• FE Terminal: Functional earth connection point integrated on the metal housing.
• büS Service Interface: Micro-USB port located underneath the removable blind cover for parameterization via Bürkert Communicator software.

Pin Assignment Tables

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

Pin	Signal Assignment
1	Digital input +
2	GND for digital input and digital outputs
3	Digital output 2 +
4	Digital output 1 +
5	Do not connect
6	Do not connect
7	Do not connect
8	Do not connect

X4 Actuator Power Supply AG3 (M12 5-Pin, L-Coded)

Pin	Power Assignment
1	Operating voltage 24 V DC ± 10 %
2	Do not connect
3	GND (power supply ground)
4	Do not connect
FE	Functional earth, connected directly to housing

Operating Limits and Environmental Ratings

Maximum working pressure for DN 80 equipped with an AG3 10,000 N actuator and PEEK seat seal washer is rated to 17 bar(g) with fluid flow oriented below the seat. Permissible ambient temperature correlates directly with process medium temperature.

In the AG3 derating chart, Curve 1 represents devices without auxiliary modules (such as 20086946). At lower medium temperatures, ambient temperatures up to +65 °C are permissible. As medium temperatures approach +185 °C, derating applies according to standard convective dissipation boundaries.

Power Interruption Behavior

Article 20086946 is configured without the internal SAFEPOS energy storage module. Upon loss of the 24 V DC electrical supply, the linear spindle mechanically blocks in its instantaneous position under process pressure up to the rated 17 bar.

Actuator Design and Operation

Linear movement is produced by a brushless DC motor linked to a ball screw drive system, applying direct thrust to the spindle. The closed exterior features detergent resistance verified against Ecolab test method F&E/P3-E No. 40-1. Position detection is continuously monitored through an internal non-contact sensor system.

Optical Status and Manual Override

• 360° LED Light Ring: Integrated on the top blind cover, the LED ring indicates active operating states, limit positions, and diagnostic warnings by steady, flashing, or color-coded illumination.
• Mechanical Position Indicator: A yellow mechanical indicator pin visible through the transparent housing section displays valve stem travel independently of electrical supply.
• Electrical Manual Operation: Located under the quarter-turn blind cover, DIP switch 4 toggles the unit into MANUAL state, enabling valve positioning via OPEN and CLOSE push buttons.
• Mechanical Manual Override: An internal hexagonal socket (4 mm width across flats) located below the pressure compensation element on the AG3 actuator permits manual movement without electrical power.

Mechanical Override Torque Limit

When manually positioning the valve via the mechanical 4 mm hex drive, do not exceed the maximum tightening torque of 2 Nm at the travel end stops.

Maintenance and Spare Parts Replacement

Wear components on the Type 3321 are field-replaceable using factory spare part sets. Servicing can be performed on the swivel plate, packing gland seals, spindle guide, and seat assembly.

Available Replacement Part Sets for Type 3321

• Swivel Plate Set: Includes replacement swivel plate (item 2), dowel pin (item 3), and body graphite seal (item 1).
• Valve Set: Includes replacement valve seat (item 4), swivel plate (item 2), dowel pin (item 3), and graphite seal (item 1).
• Packing Gland Seal Set: Includes individual PTFE V-rings, spring elements, body graphite seal, and lubricant.
• Spindle Guide Set: Includes threaded spindle guide bushing, graphite seal, and lubricant.

Pressure Hazard and Removal Precaution

Before unbolting the actuator or disassembling valve components, isolate system pressure and vent all piping lines completely. To avoid permanent seat seal damage, always drive the valve into the fully OPEN position before unscrewing the actuator from the valve body.

Body Connection Tightening Torques

Connection Size Valve Body DN [mm]	Body Tightening Torque [Nm]
10, 15	45 ±3
20	50 ±3
25	60 ±3
32, 40	65 ±3
50	70 ±3
65	100 ±3
80	120 ±5
100	150 ±5

Spindle Guide and Seat Tightening Torques

• Spindle guide bushing: 15 Nm (for spindle diameter 14 mm on large connection sizes) or 6 Nm (for spindle diameter 10 mm).
• Uncoated valve seat DN 80 replacement: Tighten firmly using the designated seat assembly tool and torque wrench to factory specifications.
• Actuator thread lubrication: Lubricate external body connection threads with Klüber paste UH1 96-402 before reinstallation.

Calibration with X.TUNE

After reassembling the actuator to a replaced valve body or installing a new valve seat set, run the automated X.TUNE function to calibrate the physical stroke limits:

1. Rotate the blind cover counter-clockwise by 90° and lift it off.
2. Ensure the process line is fully depressurized (do not run X.TUNE under media pressure).
3. Simultaneously hold down the OPEN and CLOSE push buttons for 5 seconds.
4. Rapid flashing of the LED ring signals execution. The previous LED mode resumes once tuning is complete.