Burkert 20120787 Type 2960 control valve consists of a manual actuator and an angle seat valve body made of high-quality stainless steel. A parabolic cone enables a flow capacity that is up to 35% higher compared to conventional control valves. 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 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.

General Technical Data

Product properties
Design	Angle seat control valve
Nominal diameter	DN 10...DN 65, NPS 3/8...NPS 2 1/2
Flow direction	Flow to open (below seat)
Operating pressure	0 bar(g)...25 bar(g)
Nominal pressure	PN 25 (DIN EN 1333), Class 150 (DIN EN 1759)
Seat leakage	DIN EN 60534-4:2006 (Leakage class III for Stainless steel, Leakage class VI for PTFE and PEEK)
Kv value	5 m³/h...90 m³/h
Operating characteristic	Modified equal percentage
Operating medium	Steam, water, neutral gases, alcohols, oils, fuels, hydraulic fluids, salt solutions, alkalis, organic solvents
Medium temperature	-40 °C...+230 °C
Viscosity	Max. 600 mm²/s
Ambient temperature	-10 °C...+60 °C
Installation position	As required, preferably with actuator upright

Approvals and Conformities

• Explosion protection: ATEX (EPS 18 ATEX 2 008 X II 2G Ex h IIC T4...T2 Gb, II 2D Ex h IIIC T135 °C...T300 °C Db) and IECEx (IECEx EPS 18.0007X).
• Drinking water: Suitable for use in drinking water applications. The materials comply with the assessment principles (UBA) for materials in contact with drinking water (TrinkwasserV).
• Foods and beverages/Hygiene: FDA, USP, EC Regulation 1935/2004, China food GB Standards.

Materials

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

Dimensions

Actuator

Nominal connection size (pipe) DN	Nominal connection size (pipe) NPS	Handwheel diameter ∅ [mm]	B [mm]	H [mm]
15	1/2	45 (S)	148	148
20	3/4	45 (S)	154	154
25	1	45 (S)	163	163
32	1 1/4	110 (M)	224	224
40	1 1/2	110 (M)	224	224
50	2	110 (M)	241	241
65	2 1/2	160 (L)	290	290

Performance Specifications

Flow Characteristic

• Modified equal percentage flow characteristic.
• Higher flow values compared to globe control valves.

Operating Limits Seat Seal

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

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.

Installation

WARNING

• Installation may be carried out by authorised technicians only and with the appropriate tools.
• Do not reach into the openings of the valve body.
• Ensure a controlled restart after installation.

Set Stroke Limit

Setting the minimum and maximum stroke limit is possible as an option. 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 handwheel.
3. Screw adjusting sleeve clockwise until it comes to a stop. Minimum stroke is set.
4. Mount handwheel on actuator.
5. Move the valve to the desired maximally open position.
6. Loosen the screw on the handwheel and remove the handwheel.
7. Pull adjusting sleeve upwards and at the same time, screw anticlockwise until it comes to a stop. Maximum stroke is set.

Lock Handwheel

It is also an option to lock the handwheel to prevent unintentional or unauthorised operation of the valve.

• Handwheel size S can be locked in 12 locking positions per revolution (every 30° corresponds to 0.1 mm of stroke).
• Handwheel sizes M and L can be locked in 13 locking positions per revolution (every 27° corresponds to 0.13 mm of stroke with handwheel size M and 0.15 mm of stroke with size L).

The locking pin has a bore (Ø 3.8) and can be secured against unauthorised use with a padlock.