The Burkert Type 2031 (SKU 341480) is an externally controlled 2/2-way diaphragm valve with a pneumatic piston actuator and diaphragm seal. It uses neutral gases or air to control the flow of media. The proven and robust actuator with a stainless steel valve body ensures reliable operation in hygienic or aggressive environments. The flow-optimised valve body with minimal dead space enables high volume flow rates and a wide range of possible applications. The valve is self-draining when in the appropriate installation position.

Depending on the control function, spring force (CF A) or pneumatic pilot pressure (CF B, CF I) generates the closing force. A spindle connected to the actuator piston transfers the force to the compressor, which presses the diaphragm against the weir in the valve body. SKU 341480 is configured with Control Function A (CF A), meaning it is a pneumatically operated 2/2-way on/off valve that is closed by spring force in the rest position.

Product Overview

1. Transparent cap with position indicator
2. Actuator cover
3. Upper pilot air port (for CF A and CF I)
4. Lower pilot air port (for CF A and CF I)
5. Diaphragm bonnet
6. Diaphragm
7. Body screw
8. Port connection
9. Valve body

Product Identification

1. Type
2. Control function
3. Diaphragm size
4. Diaphragm material
5. Valve body material
6. Operating pressure
7. Pilot pressure
8. CE marking
9. Manufacture code
10. Article number
11. Serial number
12. Port connection

Technical Data

Permissible Temperatures

Ambient temperature:

Actuator housing material	Actuator size	Permissible ambient temperature [°C]
PPS	≤80 (F)	+5...+140
PPS	100 (G), 125 (H)	+5...+90 (short-term up to +140)
PA	≤125 (H)	-10...+60
PA	≥175 (K)	-10...+50

Medium temperature:

Valve body material	Permissible medium temperature [°C]
Stainless steel	-10...+140 (short-term up to 150)

Medium temperature for diaphragms: The specified medium temperatures only apply to media that do not attack the diaphragm materials or cause it to swell up. The functional properties and, in particular, the service life of the diaphragm can deteriorate as the medium temperature rises. Do not use the diaphragms as a steam shut-off element.

Diaphragm material	Medium temperature [°C]	Comments
EPDM (AD)	-10...+143	Steam sterilisation max. +150°C for 60 min
FKM (FF)	0...+130	No steam, dry heat max +150°C for 60 min
PTFE (EA)	-10...+130	Steam sterilisation max. +140°C for 60 min
Advanced PTFE (EU)	-5...+143	Steam sterilisation max. +150°C for 60 min
GYLON® (ER)	-5...+130	Steam sterilisation max. +140°C for 60 min

Operating Pressure

Permissible operating pressure depending on medium temperature in plastic valve body:

INFO

The information in the pressure-temperature diagram is important for material selection. Observe the permissible operating pressure, depending on the medium temperature!

Maximum permissible operating pressure for control function A:

Diaphragm size	Actuator size	Pilot pressure [bar]	Max operating pressure EPDM, FKM (Dynamic) [bar]	Max operating pressure EPDM, FKM (Static) [bar]	Max operating pressure PTFE (Dynamic) [bar]	Max operating pressure PTFE (Static) [bar]
6	40 (C)	5.0–7	10	10	10	10
8	40 (C)	5.0–7	10	10	10	10
15	50 (D)	5.0–7	8.5	10	-	-
15	63 (E)	5.0–7	10	10	10	10
20	63 (E)	5.5–7	10	10	5	10
20	80 (F)	5.0–7	10	10	10	10
25	80 (F)	5.5–7	10	10	7.5	10
32	100 (G)	5.5–7	10	10	8	10
40	100 (G)	5.5–7	6.5	10	6	9
40	125 (H)	5.5–7	10	10	10	10
50	100 (G)	5.5–7	4.5	7.5	2.5	5
50	125 (H)	5.5–7	8	10	7	10
65	125 (H)	5.5–7	7	7.5	4	5
65	175 (K)	5.0–6	8	10	5	6
80	175 (K)	5.0–6	5	7	3	4
80	225 (L)	5.0–6	10	10	7	10
100	225 (L)	5.0–6	8	10	4	7

Pilot Pressure

Risk of bursting due to overpressure

If the device bursts, escaping media may cause injuries, burns or scalds. Do not exceed the maximum permissible pilot pressure or maximum permissible operating pressure. Observe specifications on the type label.

Minimum pilot pressure for control function A:

Diaphragm size	Actuator size	Minimum pilot pressure [bar] at 0 bar operating pressure	Minimum pilot pressure [bar] at maximum operating pressure
6	40 (C)	5	4
8	40 (C)	5	4
15	50 (D)	5	3.5
15	63 (E)	5	4
20	63 (E)	5.5	4
20	80 (F)	5	4
25	63 (E)	5	4.5
25	80 (F)	5.5	4.5
32	100 (G)	5.5	4
40	100 (G)	5.5	4
40	125 (H)	5.5	4
50	100 (G)	5.5	3.5
50	125 (H)	5.5	3
65	125 (H)	5.5	4.5
65	175 (K)	6	4.5
80	175 (K)	6	5
80	225 (L)	6	5
100	225 (L)	6	5

Installation

Ensuring Self-Draining

The installer and the operator are responsible for ensuring self-draining. The following points must be observed for optimum self-draining:

1. Inclination angle of the pipeline: The inclination angle is determined by the installer or operator. It should correspond to the inclination angle of the pipeline. For pipelines, the inclination angles specified in the valid ASME BPE standard are recommended.
2. Self-draining angle for valve body: The self-draining angle (α) depends on the size of the valve body (diaphragm size) and the inner diameter of the port connection (nominal diameter). The marking for self-draining angles on the port connection serves as a guide and must point upwards.

β = Inclination angle of the pipeline, α = Self-draining angle, 1 = Marking for self-draining

Welding the Valve Body into the Pipeline

Damage to the diaphragm or the actuator

The diaphragm and actuator can be damaged when welding or bonding the valve body into the pipeline. Remove the actuator and diaphragm from the valve body before installation.

1. Remove the actuator from the valve body.
2. Weld the valve body into the pipeline.
3. After welding the surface of the valve body, smooth by sanding if necessary.
4. Clean the valve body carefully.
5. Install the actuator on the valve body.

Maintenance

Wearing Parts

Components which are subject to natural wear are seals and the diaphragm. If leaks occur, replace the affected wearing parts with suitable spare parts. The relief bore must be inspected at regular intervals for any medium leakages. A bulging diaphragm may reduce the flow rate.

Inspection Intervals

• After the first steam sterilisation and when required: Tighten the body screws crosswise.
• After 100,000 switching cycles at the latest: Check the diaphragm for wear.
• Shortened inspection intervals are required for muddy and abrasive media.

Service Life of the Diaphragm

The service life of the diaphragm depends on the diaphragm material, medium, medium pressure, medium temperature, actuator size, and pilot pressure. To increase the diaphragm service life for CF A, match the actuator size (actuator force) to the medium pressure to be actuated.