BURKERT 346227 (Type 2100) is a pneumatically operated 2/2-way angle seat valve engineered for decentralized process automation in hygienic, chemical, and demanding utility duties. The valve features a DN 15 investment-cast CF3M stainless steel body with a clamp process connection according to DIN 32676 series B for ISO 4200 pipelines. Operating under control function A (normally closed by spring force), the valve routes fluid below the seat, eliminating hydraulic pressure surges and water hammer in liquid duties while maintaining an operating pressure rating of 25 bar(g) and a flow coefficient Kv of 5.3 m³/h.

Built on the ELEMENT platform, article 346227 integrates a Ø 50 mm (size D) pneumatic actuator featuring a polyphenylene sulphide (PPS) cover, an electropolished 1.4561 (316Ti) casing, and internal pilot air routing. Dynamic stem sealing is maintained by a self-adjusting PTFE V-ring packing gland with spring compensation, backed by an inspection relief bore. All wetted metallic and polymer components satisfy European Regulation (EC) No 1935/2004 for food contact, and the assembly supports full Clean-in-Place (CIP) and Steam-in-Place (SIP) sterilization routines.

Technical Specifications

Specification Parameter	Value / Engineering Classification
Article Number	346227
Valve Type	2100 (ELEMENT on/off valve series)
Valve Construction	Complete pre-assembled valve assembly
Number of Ports / Positions	2 ports / 2 positions (2/2-way)
Control Function	CF A: Normally closed by spring force
Flow Direction	Flow below the seat (flow to open)
Nominal Diameter (DN)	DN 15 (Seat diameter: 15 mm)
Flow Coefficient Kv (Water, +20 °C)	5.3 m³/h
Process Connection	Clamp DIN 32676 series B (Pipe standard: ISO 4200 / DIN EN ISO 1127)
Clamp Flange Outer Diameter	50.5 mm
Pipe Interface Dimensions	21.3 mm OD × 1.6 mm wall thickness (ID: 18.1 mm)
Face-to-Face Length (LC)	156 mm
Operating Pressure Range	0 bar(g) to 25 bar(g)
Nominal Pressure Class	PN 25 (DIN EN 1333) / Class 150 (ASME B16.34)
Pilot Pressure Range	5.2 bar(g) to 10 bar(g) (minimum pilot pressure: 5.2 bar)
Control Medium	Filtered compressed air, neutral gases
Pilot Air Port	Push-in connector Ø 6 mm (Interface ELEMENT)
Seat Leakage Class	Leakage rate A according to DIN EN 12266-1 (Air test medium)
Operating Media	Steam, water, neutral gases, alcohols, oils, fuels, hydraulic fluids, alkalis, saline solutions, organic solvents
Dynamic Viscosity Limit	Maximum 600 mm²/s
Medium Temperature Range	-10 °C to +185 °C
Ambient Temperature Range	-10 °C to +100 °C (-10 °C to +60 °C with push-in pilot air connectors)
Housing Enclosure Rating	IP65 / IP67 according to EN 60529, NEMA Type 4X
Cleanability Compliance	CIP capable, SIP capable
Hygienic Compliance	Regulation (EC) 1935/2004 compliant wetted materials

Principle of Operation and Control Function

BURKERT 346227 operates under Control Function A (normally closed, NC). In the unpressurized rest state, internal pre-tensioned springs exert downward force on the actuator piston. This force transfers through the 1.4401/1.4404 stainless steel spindle to press the swivel plate with its PTFE seal against the valve seat.

When pilot air at a minimum pressure of 5.2 bar(g) enters pilot air port 1, it acts on the lower chamber of the actuator piston, overcoming the mechanical spring pack and retracting the spindle upward to open the valve orifice. Because fluid enters under the seat, operating line pressure assists the opening movement. When pilot air exhausts through port 1, spring force returns the swivel plate to the closed seat position against the oncoming flow.

Flow Direction Restrictions

Do not use valves configured with flow above the seat on liquid media. Rapid closure with flow above the seat creates severe hydraulic pressure shock (water hammer) that damages pipework and valve internals. BURKERT 346227 utilizes flow below the seat, preventing water hammer across liquid, steam, and gas applications.

Materials of Construction

All components are selected for resistance to aggressive chemical washdowns, high operating temperatures, and steam sterilization. Lubricants applied to the packing gland and actuator mechanism are rated NSF H1 for food and beverage safety.

Item No.	Component Part	Material Specification
1	Ground terminal	Stainless steel 1.4301 / 1.4305 (supplied with ATEX mechanical configurations)
2	Optical position indicator	Polysulfone (PSU) transparent cap
3	Pilot air ports	Polypropylene (PP) push-in connectors (Standard) / Thread G 1/8" (1.4305 optional)
4	Actuator cover	Polyphenylene sulphide (PPS)
5	Actuator casing	Stainless steel 1.4561 (316Ti)
6	Piston seal	Fluoroelastomer (FKM)
7	Actuator springs	Stainless steel 1.4310
8	Guide pipe	Stainless steel 1.4401 (316) / 1.4404 (316L)
9	Packing gland	Self-adjusting filled PTFE V-rings with Belleville spring washer compensation
10	Valve spindle	Stainless steel 1.4401 (316) / 1.4404 (316L)
11	Spindle guide bushing	Polyetheretherketone (PEEK)
12	Body seal	Graphite (PTFE optional)
13	Swivel plate	Stainless steel 1.4401 (316) / 1.4404 (316L)
14	Seat seal	Virgin PTFE (Polytetrafluoroethylene)
15	Valve body	Investment cast stainless steel CF3M (equivalent to 1.4409 / AISI 316L)

Dimensions and Connection Details

The Ø 50 mm actuator (size D) on BURKERT 346227 has an overall envelope diameter ∅A of 64.5 mm. The valve body features a face-to-face length of 156 mm with sanitary clamp end fittings matching DIN 32676 series B.

Actuator Envelope Dimensions

Nominal Diameter	Actuator Size	Actuator Outer ∅ A [mm]	Dimension B [mm]	Dimension H [mm]	Dimension K/M [mm]
DN 15 (1/2")	50 mm (D)	64.5	166	163	147
DN 15 with Type 8690 / 8697	50 mm (D)	64.5	226	226	-
DN 15 with Type 8691 / 8695	50 mm (D)	64.5	239	239	-

Note: Dimensions B, H, K, and M represent maximum boundary clearances and may vary by up to 6 mm depending on connection tolerance.

Clamp Connection Dimensions (DIN 32676 Series B)

Nominal Diameter (DN)	Pipe Standard	Installation Length LC [mm]	Centerline Height CC [mm]	Clamp Flange ∅ D1 C [mm]	Pipe Outer ∅ D2 C [mm]	Wall Thickness SC [mm]
DN 15	ISO 4200 / DIN EN ISO 1127	156	49.0	50.5	21.3	1.6

Fluidic Performance and Operating Limits

BURKERT 346227 provides a flow coefficient Kv of 5.3 m³/h with water at +20 °C under 1 bar differential pressure. The maximum permissible operating pressure of 25 bar(g) is maintained across the entire standard temperature envelope when paired with a minimum control air supply of 5.2 bar(g).

Operating Pressure Derating by Medium Temperature (PN 25 per DIN EN 12516-1)

Medium Temperature [°C]	Maximum Permissible Operating Pressure [bar(g)]
-10 °C to +50 °C	25.0
+100 °C	24.5
+150 °C	22.4
+185 °C	20.8
+200 °C	20.3
+230 °C	19.0

Ambient and Control Air Temperature Boundaries

• Push-in pneumatic fittings (PP): Medium temperature -10 °C to +230 °C; ambient limit -10 °C to +60 °C.
• Metallic threaded pilot bushings (G 1/8"): Medium temperature -10 °C to +230 °C; ambient limit -10 °C to +100 °C.
• Mounted control units (Type 8691, 8695, 8690, 8697): Ambient boundary restricted to -10 °C to +55 °C or +60 °C based on module specifications.

Decentralized Automation and Accessories

BURKERT 346227 supports modular field integration with dedicated ELEMENT automation units to form an automated valve system (Type 8801-YE).

• Control Head Type 8695: Optimized for Ø 50 mm actuators. Features non-contact inductive position sensing, internal pilot solenoid valve with manual override, automatic stroke teach function, coloured high-visibility status LEDs, and communication options including AS-Interface, IO-Link, and büS.
• Pneumatic Control Unit Type 8697: Compact position feedback unit for Ø 50 mm actuators featuring mechanical or inductive limit switches, integrated pilot air switching, IP65/IP67 ingress rating, and optional intrinsically safe ATEX/IECEx certification.

Installation and Assembly

Before piping installation, flush lines thoroughly to clear welding slag, swarf, and debris. Mount the valve preferably with the actuator upright, observing the directional flow arrow cast into the CF3M valve body.

Actuator Rotation

The actuator connection can be rotated 360° to position pilot ports conveniently without altering piping alignments.

Procedure to Rotate the Actuator

1. Clamp the CF3M valve body securely in an appropriate vise or fixture.
2. Apply 5.0 bar compressed air to pilot air port 1 to lift the PTFE seal off the valve seat. Opening the valve prevents torsional shearing of the seat seal.
3. Hold the hex flats of the body connection using an open-end wrench.
4. Apply a second open-end wrench to the hexagonal interface of the actuator connection and rotate strictly in the designated direction until the pilot ports align with the field supply tubing.

Actuator Body Connection Tightening Torques

When reinstalling the actuator onto the valve body after maintenance or welding, apply food-grade lubricant (such as Klüberpaste UH1 96-402) to the threads, verify the condition of the body seal ring, open the valve pneumatically, and tighten to specification:

Nominal Diameter (DN)	Actuator Diameter Size	Tightening Torque [Nm]	Tolerance [Nm]
DN 15	40 mm (C), 50 mm (D), 63 mm (E)	45	+10 / -5
DN 20	40 mm (C), 50 mm (D), 63 mm (E), 80 mm (F)	50	+10 / -5
DN 25	50 mm (D), 63 mm (E), 80 mm (F)	60	+10 / -5
DN 32	63 mm (E), 80 mm (F), 100 mm (G)	65	+10 / -5
DN 40	63 mm (E), 80 mm (F), 100 mm (G), 125 mm (H)	65	+10 / -5
DN 50	70 mm (M), 90 mm (N), 100 mm (G), 125 mm (H)	70	+10 / -5
DN 65	80 mm (F), 100 mm (G), 125 mm (H)	70	+10 / -5
DN 80	125 mm (H), 130 mm (P)	120	+10 / -5
DN 100	125 mm (H), 175 mm (K), 225 mm (L)	150	+10 / -5

Pneumatic Connection

• Pilot Connection: Connect dry, filtered pilot air (quality class per ISO 8573-1) to port 1 using 6 mm external diameter pneumatic tubing.
• Exhaust Port 2: Fit the supplied porous silencer into port 2 to attenuate exhaust noise and prevent environmental dust ingestion.
• Corrosive Environments: In aggressive atmospheres, duct exhaust air from port 2 through pneumatic tubing to a neutral area.

Maintenance and Troubleshooting

Periodic maintenance involves regular visual inspection for external leakage across the process clamp joints, the packing gland relief bore, and the valve seat.

Inspection Checklist

Inspection Point	Observed Condition	Corrective Maintenance Action
Media Connection (1)	Leakage at sanitary clamp joint	Check and replace clamp gasket; re-torque clamp union
Relief Bore (2)	Process fluid weeping from actuator base	Replace stem packing gland assembly or actuator cartridge
Valve Seat (3)	Internal leakage through closed valve	Inspect seat orifice for debris; replace worn PTFE swivel plate

Operational Troubleshooting

Fault Symptom	Root Cause	Corrective Action
Actuator fails to stroke	Pilot pressure below 5.2 bar threshold	Increase pilot air line pressure to 5.2–10.0 bar range
	Pilot air line connected to wrong port	Connect control line to pilot air port 1
	Operating medium pressure exceeds 25 bar	Verify process pressure conforms to nameplate limits
Valve leaks across the seat	Debris lodged between PTFE seal and seat	Dismantle, flush line, and install upstream strainer
	Worn or deformed PTFE seat seal	Replace swivel plate assembly
	Reverse flow orientation	Verify process flow enters below the seat
Fluid leaks from relief bore	Worn V-ring spindle packing seal pack	Replace packing gland using installation tool (article 683221)

Service Tooling for Packing Gland Replacement

To overhaul the stem seal cartridge without damaging the guide threads, use the dedicated Bürkert packing gland socket wrench:

• Spindle diameter: 10 mm (suits DN 15 to DN 50 valves)
• Wrench flat size: 19 mm
• Tool Article Number: 683221

Conformity and Explosive Atmosphere Safety

BURKERT 346227 complies with Pressure Equipment Directive (PED) 2014/68/EU and Machinery Directive 2006/42/EC. For installations in hazardous environments under optional ATEX/IECEx code PX51 (EPS 18 ATEX 2 008 X / IECEx EPS 18.0007X, Ex h IIC T4…T2 Gb / Ex h IIIC T135 °C…T300 °C Db), mechanical ground bonding must be installed.

Electrostatic Discharge Hazard in Ex Areas

Frictional cleaning on non-metallic surfaces can accumulate electrostatic charges. Clean external actuator surfaces only with a damp or anti-static cloth. Electrically bond the stainless steel valve body to pipeline ground using a conductive strap, and connect exposed metallic actuator housings to plant potential equalization via the ground terminal.