BURKERT 20131008 (Type 2032) is an externally piloted 3/2-way T-diaphragm valve designed for zero dead leg sampling, distribution, and drainage in ultra-pure and hygienic process systems. The unit integrates a pneumatically actuated piston drive, an EPDM high-temperature diaphragm, and a machined stainless steel block body with 1" ASME BPE welded ends. Configured in Control Function B (normally open by spring force), the valve remains open in its unpressurised state and closes upon pneumatic pilot actuation, delivering leak-tight shut-off across an operating pressure span from 0.00 to 10.00 bar.

Constructed from forged/block stainless steel 1.4435 (DIN EN 10088) / 316L (ASTM A479), the wetted interior is electropolished to Ra ≤ 0.38 µm (ASME BPE SF4 / DIN HE4). The valve complies with ASME BPE / DIN 11866 Series C piping standards (outer diameter 25.4 mm, wall thickness 1.65 mm). The autoclavable polyphenylene sulphide (PPS) actuator housing withstands ambient operating temperatures from +5 °C to +140 °C, supporting both CIP (clean-in-place) and SIP (sterilise-in-place) cycles up to +150 °C for 60 minutes.

Technical Specifications

Specification Parameter	Value / Range
Article Number	20131008
Valve Type	Type 2032 (CLASSIC)
Fluidic Ports	3 ports, 2 switching positions (3/2-way T-body)
Control Function	Control Function B (CF B) — normally open (NO) by spring force
Body Nominal Size	20 mm
Port 1 Connection	Weld end 1" (DN 25), ASME BPE / DIN 11866 Series C
Pipe Dimensions	Outer Ø 25.4 mm (1.000"), Inner Ø 22.1 mm, Wall thickness 1.65 mm (0.065")
Body Material	Stainless steel block 1.4435 / 316L (BN2 on request)
Surface Roughness (Internal)	Ra ≤ 0.38 µm (electropolished, ASME BPE SF4 / DIN HE4)
Surface Roughness (External)	Ra ≤ 1.6 µm
Actuator Material	PPS (Polyphenylene sulphide), autoclavable
Actuator Piston Seal	FKM (Fluor rubber)
Diaphragm Material	EPDM high-temperature (AD code)
Operating Medium Pressure	0.00 bar to 10.00 bar (gauge)
Nominal Pressure Rating	PN 16 (DIN EN 1333) / Class 150 (DIN EN 1759)
Pilot Control Pressure Range	2.0 bar to 7.0 bar
Pilot Air Connection	G 1/4 internal thread
Medium Temperature Range	-10 °C to +143 °C (steam sterilisation max. +150 °C for 60 min)
Ambient Temperature Range	+5 °C to +140 °C
Certificates Included	EN 10204 3.1 inspection certificate, Factory certification 2.1 Membrane

Control Function and Operating Principle

BURKERT 20131008 operates under Control Function B (CF B). Internal springs maintain the diaphragm in an open position relative to the valve seat when no pilot air is applied. Supplying compressed air (2.0 to 7.0 bar) to the upper pilot port forces the piston actuator downward against spring tension, pressing the EPDM diaphragm firmly onto the machined weir of the T-body to isolate the branch line.

INFO

Control Function B requires pilot air connection to the upper pneumatic port only. For optimal diaphragm service life, set the pilot pressure to the minimum pressure required to counteract medium line pressure according to operating pressure curves, rather than operating continuously at maximum pilot pressure.

Materials of Construction

Item No.	Component	Material
1	Transparent Position Indicator Cap	Polysulfone (PSU)
2	Actuator Cover Housing	Polyphenylene sulphide (PPS, autoclavable)
3	Pilot Air Ports	Stainless steel 1.4305
4	Piston Seal	FKM (Fluor rubber)
5	Socket	Sinter metal
6	Actuator Interface / Bonnet	Stainless steel 1.4404 (316L)
7	Diaphragm	EPDM high-temperature (AD)
8	T-Valve Body	Stainless steel block material 1.4435 / 316L

Diaphragms for Type 2032 meet stringent sanitary, pharmaceutical, and food-grade regulations:

• EPDM (AD): -10 °C to +143 °C (steam sterilisation up to +150 °C for 60 min), FDA and USP Class VI compliant.
• PTFE/EPDM (EA): -10 °C to +130 °C (steam sterilisation up to +140 °C for 60 min).
• Advanced PTFE/EPDM (EU): -5 °C to +143 °C (steam sterilisation up to +150 °C for 60 min).
• GYLON® / EPDM laminate (ER): -5 °C to +130 °C (steam sterilisation up to +140 °C for 60 min).

Dimensional Specifications

Welded T-Body Dimensions (ASME BPE / DIN 11866 Series C)

Diaphragm Size	Port 1 – Port 2 DN	ØD1 [mm]	s1 [mm]	ØD2 [mm]	s2 [mm]	A [mm]	B [mm]	C [mm]	E [mm]	F [mm]	G [mm]	H [mm]	I [mm]	Product Key
25	25 to 25 (1")	25.40	1.65	25.40	1.65	124.5	25.0	74.8	25.0	95.0	42.0	26.0	6.0	SODF-SODF

CLASSIC Actuator Dimensions (Diaphragm Size 25)

Diaphragm Size	Actuator Size Ø [mm]	Actuator Outer ØA [mm]	C Dimension [mm]	Pilot Port K	Height H [mm]	HM + MT85 Height [mm]
25	63 (E)	80	52	G 1/4	170	266
25	80 (F)	101	60	G 1/4	190	286

Operating Conditions and Pressure Limits

BURKERT 20131008 features an operating medium pressure capability from 0 to 10 bar static pressure for EPDM seals. The pilot supply pressure must be regulated between 2.0 and 7.0 bar. For Control Function B with EPDM diaphragms, the required pilot closing pressure is governed by operating line pressure.

Temperature and Medium Limits

• Specified medium temperatures apply strictly to media that do not chemically attack or swell the elastomer membrane.
• Diaphragm longevity decreases with elevated operating temperatures; do not use the diaphragm as a continuous steam barrier.
• Ensure ambient temperature remains within +5 °C to +140 °C for the PPS actuator.

Installation and Pipeline Integration

To ensure complete drainability and compliance with sanitary processing guidelines, follow these installation rules:

1. Pipeline Slope: Maintain a pipeline slope of 1° to 5° along the process run.
2. Leak Detection Orientation: Locate the leakage detection hole on the diaphragm bonnet at the lowest physical point of the assembly.
3. Welding Preparation: Disassemble the actuator and diaphragm from the valve block before orbital or manual welding into the line. Thermal transfer during welding will permanently deform the EPDM membrane and PPS housing if uncoupled.
4. Flushing: Flush and clean the line thoroughly of welding debris, slag, and particulates before reattaching the actuator and diaphragm.

For Control Function B, connect clean, dry control air to the upper pilot air connection (G 1/4). In aggressive or washdown atmospheres, vent the lower port through tubing to a neutral area.

Maintenance and Diaphragm Replacement

Routine maintenance involves checking the bonnet weep hole for medium leakage and examining the diaphragm for mechanical fatigue after 100,000 switching cycles or after aggressive steam sterilisation.

Replacement Procedure for Control Function B

1. Depressurise the fluid system and vent all fluid lines.
2. Disconnect pneumatic supply from the upper air port.
3. Loosen fastening body screws in a crosswise sequence and detach the PPS actuator.
4. Rotate the diaphragm bayonet fitting 90° to detach it from the drive spindle (or unscrew threaded pins where fitted).
5. Mount the replacement EPDM diaphragm (article ordering key 688 424 for DN 25 EPDM AD). Align the diaphragm tabs perpendicular to the flow axis.
6. For threaded pins, screw the pin in completely, then back it off half a turn counter-clockwise to prevent pin tension stress.
7. Position the actuator onto the body. Lightly tighten the housing bolts crosswise without pressure.
8. Apply pilot air to the upper port to stroke the valve twice, ensuring the membrane seats uniformly.
9. Under applied pilot pressure, tighten the body bolts in three progressive stages (approx. 1/3, 2/3, and 3/3 of total torque) in a crosswise pattern.

Diaphragm Size (DN)	Tightening Torque for Block Body (VS) — EPDM / FKM [Nm]	Tightening Torque for Block Body (VS) — PTFE / GYLON [Nm]
8	2.0	2.5
15	3.5	4.0
20	4.0	4.5
25	5.0	6.0
32	6.0	8.0
40	8.0	10.0
50	12.0	15.0
65	20.0	30.0

Tightening Tolerance

Tightening torque tolerance across all body bolts is +10%. Retighten bolts crosswise after the first operational steam sterilisation cycle to compensate for elastomer relaxation.

Automation Units and Combinations

BURKERT 20131008 combines directly with Type 8697 pneumatic control and electrical position feedback units (actuator sizes Ø 40 to 225 mm). The Type 8697 features an IP65/IP67 chemically resistant enclosure, integrated optical LED indicators, and mechanical or inductive limit switches for automated plant monitoring. Combining the Type 2032 valve with Type 8697 forms the factory-tested on/off valve system Type 8801-TA.