BURKERT 20127850 (Type 2933) is a 2/2-way manually operated diaphragm valve designed for hygienic and aggressive ambient conditions. This specific configuration features a DN 15 welded connection, an investment cast 316L/1.4435 stainless steel valve body, and a PTFE diaphragm with an EPDM backing membrane. The manual actuator is equipped with a stainless steel handwheel, an integrated visual position indicator with a scale, and a single minimum-stroke limiter (closing limiter). The flow-optimised valve body with minimum dead space enables high flow values and reliable operation at pressures up to 10 bar and temperatures up to 130 °C.

Approvals and Conformities

The 20127850 diaphragm valve complies with stringent industry standards for food, beverage, and pharmaceutical applications:

• FDA: The PTFE/EPDM diaphragm complies with the Code of Federal Regulations published by the FDA.
• USP Class VI: The diaphragm material is tested according to United States Pharmacopeial Convention (USP) Class VI.
• EC 1935/2004: Suitable for use with food and beverages according to EC Regulation 1935/2004/EC.

Material Specifications

No.	Element	Material
1	Handwheel	Stainless steel (specific to SKU 20127850)
2	Visual position indicator	Polyamide (PA), Stainless steel 1.4305
3	Valve spindle	Stainless steel 1.4305
4	Diaphragm bonnet	Stainless steel (specific to SKU 20127850)
5	Diaphragm	PTFE with EPDM backing membrane (EA)
6	Valve body	Investment cast material 316L/1.4435 (VG)

Dimensions

Manual Actuator

Diaphragm size	H1 (mm)	H2 (mm)	Ø B (mm)
15	84	78	45

Cast Valve Body (VG) with Welded Connection

Diaphragm size	Port connection DN	ØD1 (mm)	s (mm)	L (mm)	h (mm)	H (mm)
15	15	21.3	1.6	110	13.5	25.0

Note: Dimensions correspond to DIN EN ISO 1127 / ISO 4200 / DIN 11866 series B.

Performance Specifications

Flow Characteristics

• Kv value (water): 5.3 m³/h (JSON specification) / 5.6 m³/h (Datasheet reference for DN 15 Cast Valve Body).
• Measurement at +20 °C, 4 bar at valve inlet and 3 bar at valve outlet.

Medium Pressure and Tightening Torque

Diaphragm size	Maximum static operating pressure	Tightening torque for PTFE/EPDM
15	10 bar	1.7 Nm

WARNING

The tightening torques refer to the static media pressures specified above. Excessive torque can shorten the service life of the diaphragm. A tolerance of +10% applies to the tightening torques specified.

Installation

Installation Position for Self-Draining

It is the responsibility of the installer and the operator to ensure self-draining. Observe the rules for self-draining during installation:

1. Inclination angle of the pipeline: The angle of inclination should correspond to the angle of inclination of the pipeline. For the pipeline, we recommend the inclination angles according to the valid ASME BPE.
2. Self-draining angle for valve body: The self-draining angle (α) depends on the valve body size and the inner diameter of the port connection (DN). The marking on the port connection of the valve body serves as an orientation aid and must point upwards.

Fastening Screws Tightening Torque

When installing the actuator onto the valve body, tighten each fastening screw in 3 stages (approx. 1/3, approx. 2/3, 3/3 of the tightening torque) crosswise. The diaphragm should be positioned and pressed evenly around the actuator and valve body.

• Diaphragm Size 15 (PTFE/EPDM): 4 Nm (+10% tolerance).