BURKERT 20095124 Type 2973 is a 2/2-way diaphragm valve with a manually operated actuator. Designed for hygienic, sterile, and aggressive media, this valve features a stainless steel tube valve body (316L/1.4435 BN2) and an advanced PTFE diaphragm with an EPDM backing membrane. The manual actuator is constructed with a PPS handwheel and a stainless steel bonnet, ensuring compatibility with demanding environments and autoclavable requirements. It includes an optical position indicator, a minimum and maximum stroke limiter, and a locking mechanism to prevent unauthorised operation.

Product Structure and Materials

The Type 2973 manual diaphragm valve consists of a manual actuator, a diaphragm, and a 2-way tube valve body. The flow-optimized and zero-dead-volume valve body enables high flow rates and a wide range of possible uses.

Item	Component	Material
1	Locking pin	Stainless steel 1.4305
2	Bolt	Stainless steel A2
3	Handwheel cover	Polyamide (PA)
4	Handwheel	Polyphenylene sulphide (PPS)
5	Visual position indicator	Polyamide (PA)
6	Spindle	Stainless steel 1.4305
7	Diaphragm bonnet	Stainless steel 1.4308
8	Diaphragm	Advanced PTFE/EPDM
9	Valve body	Stainless Steel Tube 316L/1.4435 BN2

Product Identification

Item	Description	Item	Description
1	Company logo	5	Nominal diameter and pipe dimensions
2	Material	6	Serial number
3	Heat	7	Self-draining angle
4	Nominal pressure

Technical Data

Approvals and Conformity

The diaphragms made from Advanced PTFE/EPDM are tested according to USP Class VI and are suitable for food and beverages according to EC Regulation 1935/2004 and FDA guidelines.

• Medium Temperature: -5 °C to +143 °C (Steam sterilisation up to +150 °C for 60 min)
• Ambient Temperature: -10 °C to +130 °C (up to +150 °C for short periods), autoclavable
• Maximum Permitted Medium Pressure: 10 bar
• Kv Value (Water): 6.5 m³/h

Dimensions

Tube Valve Body (VP) with Welded Connection (ASME BPE / DIN 11866 Series C)

Diaphragm Size	Port Connection	∅D1	s	L	h	H	Product Code
15	3/4 inch	19.05	1.65	117.0	13.23	25.73	SA93

(Dimensions in mm unless otherwise stated)

Setting Stroke Limit

A minimum and maximum stroke limit can be set for Type 2973. An adjusting sleeve is used for this purpose.

1. By turning the handwheel clockwise, the valve is moved to the closed position.
2. Loosen the screw on the handwheel (hexagon socket, width across flats 2) and remove the handwheel.
3. Screw the adjusting sleeve clockwise until it comes to a stop. Minimum stroke is set.
4. Mount the handwheel on the actuator. The square on the spindle and the hexagon head of the adjusting sleeve must be correctly aligned.
5. Move the valve to the desired maximally open position.
6. Loosen the screw on the handwheel and remove the handwheel.
7. Pull the adjusting sleeve upwards and at the same time, screw anticlockwise until it comes to a stop. Maximum stroke is set.
8. Mount the handwheel on the actuator and tighten the screw with 0.9 Nm.

Locking the Handwheel

For Type 2973, a locking mechanism is available to prevent accidental or unauthorised operation.

• A handwheel (diaphragm size 15) can be locked in 12 locking positions per revolution (every 30° corresponds to 0.15 mm of stroke).
• Push the locking pin down and rotate by 180° (either clockwise or anticlockwise). The locking pin must lock into its end position so that the bore is fully visible once again.
• Insert a padlock through the bore (Ø 3.8) in the locking pin and secure it.