

The Burkert 20111221 Type 2104 is a pneumatic diaphragm T-valve featuring a stainless steel body, EPDM seal, and PPS actuator. Ideal for hygienic applications up to 10 bar and 143°C.

The Burkert 20111221 Type 2104 is an externally controlled diaphragm T-valve consisting of a pneumatically operated piston actuator, a diaphragm, and a T-valve body. The proven and robust PPS actuator ensures reliable use in hygienic or aggressive ambient conditions. The flow-efficient stainless steel valve body features minimal dead space, enabling high flow rates and a wide range of possible uses. It is a compact, smooth-surfaced, and highly integrated system offering IP65/67 and NEMA Type 4X protection, with wetted surfaces polished to Ra ≤ 0.38 µm...≤ 1.6 µm.

| Product properties | Description |
|---|---|
| Block body material | Stainless steel block material 1.4435 according to DIN EN 10088 and 316L according to ASTM A479 / A479M |
| Diaphragm material | EPDM (AD), PTFE/EPDM (EA), Advanced PTFE/EPDM (EU), laminate of GYLON® and EPDM (ER) |
| Actuator material | DN 08...65, PPS; DN 65...100, stainless steel 1.4308 |
| Actuator casing | DN 08...65, stainless steel 1.4561 (316Ti); DN 65...100, stainless steel 1.4308 |
| Maximum pilot pressure | 10 bar (7 bar for actuator size 130, 225) |
| Pilot air port | Push-in connector for outer diameter, ∅ 6 mm or 1/4" (standard), thread G 1/8" |
| Operating medium | Neutral gases and liquids, highly purified, sterile, aggressive or abrasive mediums |
| Control medium | Neutral gases, air |
| Ambient temperature | -10 °C...+ 60 °C, autoclavable |
| Control Function | Description |
|---|---|
| Control function A (CF A) | Pneumatically operated T-valve. Normally closed by spring force. |
| Control function B (CF B) | Pneumatically operated T-valve. Normally opened by spring force. |
| Control function I (CF I) | Pneumatically operated T-valve on either side. Switching position dependent on external control. |

| No. | Element | Material |
|---|---|---|
| 1 | Ground terminal | Stainless steel 1.4301/1.4305 (only for ATEX/IECEx variant) |
| 2 | Transparent cap | Polysulfone PSU |
| 3 | Pilot air ports | Push-in connector PP (standard), Thread G 1/8" stainless steel 1.4305 |
| 4 | Actuator | Polyphenylene sulphide PPS |
| 5 | Cover | Stainless steel 1.4561 (316Ti) |
| 6 | Piston seal | FKM |
| 7 | Diaphragm | EPDM (AD), PTFE/EPDM (EA), advanced PTFE/EPDM (EU), laminate of GYLON® and EPDM (ER) |
| 8 | Valve body | Stainless steel |

| Diaphragm size | Actuator size ∅ | ∅ A | H+M (MT86) |
|---|---|---|---|
| 8 | 50 (D) | 65 | 138 |
| 15 | 50 (D) | 65 | 146 |
| 15 | 70 (M) | 92 | 166 |
| 20 | 70 (M) | 92 | 166 |
| 25 | 70 (M) | 92 | 172 |
| 25 | 90 (N) | 120 | 205 |
| 40 | 90 (N) | 120 | 221 |
| 50 | 130 (P) | 160 | 282 |

(Dimensions in mm. Excerpt for DIN EN ISO 1127 / ISO 4200 / DIN 11866 series B)
| Diaphragm size | Port 1 – Port 2 DN | ∅D1 | s1 | ∅D2 | s2 | A | B | C | E | F | G | H | I |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 15 | 15...15 | 21.3 | 1.6 | 21.3 | 1.6 | 93.0 | 20.0 | 56.0 | 20.0 | 71.0 | 35.0 | 21.0 | 6.5 |
| 15 | 20...15 | 26.9 | 1.6 | 21.3 | 1.6 | 103.0 | 25.0 | 59.8 | 20.0 | 78.0 | 42.0 | 25.0 | 11.5 |
| 20 | 20...20 | 26.9 | 1.6 | 26.9 | 1.6 | 114.0 | 25.0 | 70.3 | 25.0 | 87.0 | 40.0 | 24.0 | 6.0 |
| 25 | 25...25 | 33.7 | 2.0 | 33.7 | 2.0 | 124.5 | 25.0 | 78.6 | 25.0 | 98.0 | 53.0 | 33.0 | 13.0 |
| 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 |
Risk of bursting due to overpressure
If the device bursts, escaping media may cause injuries, burns or scalds. Observe the values indicated on the type label. Valves with reduced spring force require reduced pilot pressure.
| Diaphragm size | Actuator size | Pilot pressure [bar] | Max operating pressure (EPDM, FKM) Dynamic [bar] | Max operating pressure (EPDM, FKM) Static [bar] |
|---|---|---|---|---|
| 8 | 50 (D) | 3.7...10 | 10 | 10 |
| 15 | 50 (D) | 5.0...10 | 7.5 | 10 |
| 15 | 70 (M) | 4.8...10 | 10 | 10 |
| 20 | 70 (M) | 4.8...10 | 10 | 10 |
| 25 | 70 (M) | 5.5...10 | 6.5 | 10 |
| 25 | 90 (N) | 5.0...10 | 10 | 10 |
Installation Recommendations
Damage to the diaphragm or the actuator
The diaphragm and actuator can be damaged when welding the valve body into the pipeline. In the case of devices with a welded connection, remove the actuator and diaphragm from the valve body before installation.
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