The BURKERT Type 2933 (Article No. 20112730) is a 2/2-way diaphragm valve with a manually operated actuator. The manual actuator with a PPS (Polyphenylene sulphide) handwheel ensures reliable use in hygienic or aggressive ambient conditions. The flow-optimised forged stainless steel valve body with minimum dead space enables high flow values and a wide range of possible applications. The actuator has a compact, autoclavable design and is equipped with an integrated visual position indicator with a scale, a reproducible stroke scale, and a single min-stroke limiter (closing limiter).

This specific model features a DN 25 welded connection, a forged stainless steel 316L body, and a PTFE diaphragm with an EPDM backing membrane. It is designed to handle medium pressures up to 10 bar and temperatures ranging from -10 °C to +130 °C, making it fully CIP and SIP capable for demanding process environments.

General Technical Data

Feature	Specification
Port connection	DN 25 (NPS 1) - 29.0x1.5 Welded (DIN 11850 R2 / DIN 11866 Series A / DIN EN 10357 Series A)
Valve body material	Forged stainless steel 316L/1.4435 BN2
Diaphragm material	PTFE with EPDM backing membrane
Nominal pressure	0 - 10 bar (PN 10 / Class 150)
Medium temperature	-10 °C to +130 °C
Ambient temperature	-10 °C to +130 °C (short-term up to +150 °C), autoclavable
Kv value (water)	17 m³/h (Cv value: 19.8 gal/min)
Actuator material	PPS handwheel, optical position indicator with scale (45 mm diameter)

Approvals and Conformities

• FDA: The PTFE/EPDM diaphragm complies with the Code of Federal Regulations published by the FDA (Food and Drug Administration, USA).
• USP: Tested according to United States Pharmacopeial Convention (USP) Class VI.
• EC Regulation 1935/2004: Suitable for use with food and beverages.
• Explosion Protection: ATEX / IECEx approved as a category 2 device suitable for Zone 1/21 and Zone 2/22 (Ex h IIC T4...T2 Gb / Ex h IIIC T135 °C...T300 °C Db).

ATEX Safety Note

When operating in potentially explosive atmospheres, ensure proper grounding of the valve body and actuator to prevent electrostatic charging hazards. Only use cleaning agents certified for explosive environments.

Materials

No.	Element	Material
1	Handwheel	Polyphenylene sulphide (PPS), stainless steel 1.4308
2	Visual position indicator	Polyamide (PA), Stainless steel 1.4305
3	Valve spindle	Stainless steel 1.4305
4	Diaphragm bonnet	Stainless steel 1.4308, polyphenylene sulphide (PPS)
5	Diaphragm	PTFE with EPDM backing membrane
6	Valve body	Forged stainless steel 316L/1.4435 BN2

Dimensions

Forged Steel Valve Body (VS) with Welded Connection

Dimensions for DN 25 (DIN 11850-2 / DIN 11866 Series A / DIN EN 10357 Series A):

Diaphragm size	Port connection DN	∅D1	s	L	h	H	Product key
25	25	29.0	1.5	129	19.0	37.0	SD44

(Note: Dimensions in mm, unless otherwise stated)

Installation Guidelines

Installation Position & Self-Draining

The installation position is generally any, but preferably with the actuator facing up. To ensure self-draining, 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. The actual self-draining angle must be set with a suitable measuring tool.

Welding Instructions: To prevent damage, the actuator and diaphragm must be dismantled before welding the valve body into the pipeline. After welding, smooth the body surface if necessary and clean the valve body thoroughly before reassembling the diaphragm and actuator. Tighten the fastening screws crosswise in 3 stages to ensure the diaphragm is positioned and pressed evenly.