Burkert Type 2961 manually operated 2-way globe control valve features excellent control accuracy and exchangeable valve seats that enable perfect coordination under the most demanding operating conditions. It includes a robust actuator with optional stroke limitation and locking, and a stainless steel valve body available with flange, socket, clamp, or welded connections.

The Type 2961 control valve consists of a manual actuator and a globe valve body with exchangeable seats made of high-quality stainless steel. Each globe valve body can be equipped with up to 8 valve seat sizes and reaches the desired flow characteristic curve in interaction with parabolic cones. The precise spindle guide enables control, even under demanding operating conditions. A soft PTFE or PEEK seal guarantees reliable sealing. The actuator is made of high-quality plastic (PPS) and is suitable for use in demanding environments. It possesses a visual position indicator and can be optionally equipped with stroke limitation and locking. The packing gland uses tried-and-tested V-seals and possesses spring compensation, which means that it does not need to be pulled back manually.

Approvals and Conformities

• Explosion Protection: Optional ATEX / IECEx (Category 2 device suitable for zone 1/21 and zone 2/22).
• Drinking Water: Suitable for use in drinking water applications (materials comply with UBA assessment principles).
• Foods and Beverages/Hygiene: FDA (Code of Federal Regulations), USP (United States Pharmacopeial Convention), EC Regulation 1935/2004, and China food GB Standards.

Materials

No.	Element	Material
1	Cover	Polyamide (PA)
2	Screw	Stainless steel 1.4301
3	Locking device	Stainless steel 1.4305
4	Handwheel	Polyphenylene sulphide (PPS)
5	Visual position indicator with scale	Polyamide (PA)
6	Packing gland	PTFE V-rings (filled), with spring compensation
7	Stem	Stainless steel 1.4401 or 1.4404
8	Spindle guide	Stainless steel 1.4404 (316L), PTFE filled
9	Housing seal	Graphite
10	Control cone	1.4571 (optionally hardened)
11	Seat seal (optional)	PTFE or PEEK
12	Valve seat with O-ring	Stainless steel 1.4571, EPDM
13	Valve body	Stainless steel 316L/CF3M

Dimensions

Actuator

Nominal connection size [DN]	Nominal connection size [NPS]	Handwheel diameter ∅ [mm]	H1 [mm]	H2 (locking) [mm]
15	1/2	45 (S)	217	224
20	3/4	45 (S)	224	230
25	1	45 (S)	228	234
32	1 1/4	110 (M)	296	303
40	1 1/2	110 (M)	301	307
50	2	110 (M)	307	313
65	2 1/2	160 (L)	361	368
80	3	160 (L)	369	375
100	4	160 (L)	379	385

Performance Specifications

Flow Characteristics

• Flow characteristic according to DIN EN 60534-2-4.
• Equal percentage flow curve.
• Theoretical rangeability (Kvs / Kvo): 50:1 for valve seat size 8 to 100.

Operating Limits for Seat Seal

Tight sealing required	Leakage class (DIN EN 60534-4)	Medium temperature	Seat seal
No	II (metal seals)	-40 °C...+230 °C	Stainless steel
Yes	VI (soft seals)	-40 °C...+130 °C	PTFE
Yes	VI (soft seals)	-10 °C...+230 °C	PEEK

Optional Variants

• High-temperature variant: Suitable for applications with steam, neutral gases and other heat transfer mediums up to +230 °C.
• Water variant: For applications with water up to +200 °C, a special configuration of the packing gland increases service life significantly.
• Low-temperature variant: Suitable for minimum medium temperatures down to -40 °C.

Product Design and Assembly

Position Indicator

When turning the handwheel counterclockwise, the reproducible stroke scale becomes visible between the attachment and the handwheel. The scale on the handwheel, together with the stroke scale, enables reproducible adjustment of the flow rate.

Flow Direction

The valve seat is always closed against the medium flow. The flow direction should therefore be set such that the valve reaches the flow beneath the valve seat.

Interlock (Optional)

The valve can be secured against unintentional or unauthorized operation. For this purpose, a securing pin can be pressed down and turned. The locking pin has a hole (∅ 3.8) and can be secured with a padlock.

Safety and Installation Notes

WARNING

Risk of injury due to high pressure and escaping medium Switch off the pressure before working on the device or system. Vent or drain the lines.

Explosion Hazard in ATEX Zones

If the device is used in potentially explosive areas (Zones 1/21 and 2/22):

• Take appropriate measures to ensure that static electricity cannot accumulate in the potentially explosive area.
• Only wipe the surface of the device gently with a damp or anti-static cloth.
• Ground the actuator and the valve body.
• If a plastic valve body is used, ground the actuator separately.

Conductive parts must be grounded separately. Install a grounding strap or terminal and connect to a grounding point.