Danfoss VFS 2 Data sheet

Data sheet

Seated valve for steam (PN 25)

VFS 2 – Two way valve, flange

Description

VFS 2 valve is a range of 2 port flanged valve for chilled water, LPHW, MPHW, HPHW (low, medium or high pressure hot water) and steam applications.

The valve is designed to be combined with following actuators:

• DN 15-50 AMV(E) 25 (SU/SD), AMV(E) 35, AMV(E) 56 (with clutch "065Z7551")

• DN 65-100 AMV(E) 55, AMV(E) 56, AMV(E) 85,

AMV(E) 86, AMV (E) 65x

Features:

• Logarithmic characteristic

• Rangeability R= >100:1 by DN 20-100

• Suitable for steam applications

Main data:

• DN 15-100

• kVS 0.4 -145 m3/h

• PN 25

• Down to close

• Medium:

Circulation water/glycolic water up to 50 % / steam (max. p = 6 bar)

• Temperature:

At temperature s from −10 °C up to +2 °C use stem heater

2 (10

) … 200 °C

• Logarithmic characteristic

• Flange PN 25 connections

• Compliance with Pressure Equipment Directive

2014/6 8/EU.

Ordering

Example: Two way valve, DN 15, kVS 1.6, PN 25, T

200 °C, flange connection

max

- 1× VFS 2 DN 15 valve Code No.: 0 65B1513

Two way valve VFS 2

20 6.3 06 5B1520

25 10 06 5B1525

32 16 0 65B1532

40 25 06 5B1540

50 40 065B1550

65 63 065B3365

80 100 0 65B3380

100 145 065B3400

(m3/h) (°C)

0.4

0.63 06 5B1 511

1.0 06 5B1512

1.6 06 5B1513

2.5 06 5B1514

4.0 06 5B1515

25 200

max.

065 B1510

Code No.

Spare parts – stuffing box

DN Description Co de No.

100

Four PTFE rings

Seal for valve cover

Gland ring

Washer

Instructions

Three PFTE rings

Gland ring

Instructions

065B0001

065B000680

Accessories

Typ e Code No.

Stem heater 24 V AC/DC (AMV(E) 25, 35 and VFS 2 valves DN 15-50)

Stem heater 24 V AC/DC (AMV(E) 56 and VFS 2 valves DN 15-50)

Stem heater 24 V AC/DC (AMV(E) 85, 86 and and VFS 2 valves DN 65-100)

Stem heater 24 V AC/DC (AMV(E) 55, 56, 655, 658, 659 and VFS 2 valves DN 65-100)

Adapter AMV(E) 25 (SU/SD), AMV(E) 35 and VFS 2 DN 15-50 (for media temperatures over 150 °C)

Clutch (AMV(E) 56 and VFS 2 valves DN 15-50)

06 5B2171

065Z7020

065Z7021

065Z7022

065Z 7548

065Z7551

Data sheet Two way valve VFS 2

Technical data

Nominal diameter DN 15 20 25 32 40 50 65 80 100

kVS value m3/h 0.4 0.63 1.0 1.6 2.5 4.0 6.3 10 16 25 40 63 100 145

Stroke mm 15 40

Rangeability > 3 0:1 > 50:1 > 10 0:1

Control characteristic Logarithmic

Cavitation factor z 0.5 0.5 0.5 0.5 0. 5 0.5 0.4 0.3 0.3

Leakage acc. to standard IEC 534

< 0.05 % of k

Nominal pressure PN 25

Medium Circulation water/glycolic water up to 50 % /steam (max. ∆p = 6 bar)

Medium pH Min. 7, max. 10

Medium temperature °C 2 (–101)) … 200

Connections Flange ISO 7005-2

Materials

Ductile iron

Body and cover Ductile iron EN- GJS-400 -18-LT (GGG 40.3)

EN-GJS-400-15

(GGG 40)

Cone, seat and spindle Stainless steel

Gland seal Replaceable PTFE rings

At temperature s from -10 °C … +2 °C use stem heater .

Pressure temperature diagram Valve characteristics-logarithmic

DN 15-50: EN-GJS -400-18-LT (GGG-4 0.3) PN 25 DN 65-100: EN- GJS-400 -15 (GGG-40) PN 25

Max. closing pressure1) and recommended Δp

Capacity

-way

Stroke

A 

Valve Actuator

Stroke

(mm)

AMV(E) 25

[AMV(E) 25 SU/SD]

25 [223)] 25 -

15 (kVS 4.0) 25 [163)] 20 -

20 25 [103)] 13 -

25 16 [53)] 8 -

32 9 [2.53)] 5 -

40 6 [23)] 3 -

50 3 [0.53)] 2 -

80 - - 3 2 8 3

- - 4.5 3 13 4.5

AMV(E) 35 AMV(E) 55 AMV(E) 56 AMV(E) 85, 86 AMV(E) 65x

max. closing pressure 1) (bar)

- -

100 - - 1.5 1 5 1. 5

Note:

Max. Δp is t he physical limit of diffe rential pressure the valve will cl ose against. Max. Δp for ste m application is 6 bar.

The recommen ded Δp is based on the generati on of noise, plug erosion e tc. Max. re commended Δp is 4 bar. If max. c losing pressure is smaller tha n 4 bar than the recommended Δ p is the same as closing Δp.

Values in parenth eses [ ] are based on the force of the ac tuator AMV(E) 25 SU/SD only.

With stem connec tor (On request)

2 | AI094186477177en-010404 © Danfoss | 2022.01

Data sheet Two way valve VFS 2

Installation

≤150 °C for AMV(E) 25 (SU/SD), 35

max

≤200 °C for other AMV(E)

max

AMV(E) 25(SU/SD)/35

AMV(E) 55/56 AMV(E) 65x

= 150 ... 200 °C AMV(E) 25 (SU/SD), 35

max

AMV(E) 85/8 6

Valve mounting

Before mounting the valve be sure that the pipes are clean and free from abrasion.

It is essential that the pipes are lined up squarely with the valve at each connection and that they are free from vibrations.

Adapter for VFS 2 DN 15 -50

Always install the valve with the arrow on the body in the same direction as the ow. In order to avoid turbulence, which will aect the measuring accuracy, it is recommended to have a straight length of pipe up and down stream from the valve as shown (D - diameter of pipe).

Install the motorized control valves with the actuator in a vertical or horizontal position in accordance to recommendations described in Installation above. Note that the actuator may be rotated up to 360° with respect to the valve body by loosening the retaining fixture. After this operation retighten.

Leave sufficient clearance to facilitate the dismantling of the actuator from the valve body for maintenance purposes.

Note that the actuator may be rotated up to 360° with respect to the valve body by loosening the retaining fixture. After this operation retighten.

AMV(E)

FVR/FVF

Note:

Install a strainer upstream of the valve (e.g. Danfoss FVR/FVF)

AI094186477177en-010404 | 3© Danfoss | 2022.01

Data sheet Two way valve VFS 2

2p1p

a authority, Valve

∆+∆

∆

5.0









62.0

557.90

7.90

authority valve hence =

395.0

5536

authority valve hence =

Control valve sizing diagram for fluids

Flow liqui d with specific gravit y of 1

Flow liqui d with specific gravity different to 1

FLOW Pressure d rop kPa (100 kPa = 1 bar = ~10 m H2O) Specif ic gravity

Examples:

1 For fluids with specific gravity of 1

(e.g. water)

Design data:

Flow rate: 6 m3/h System pressure drop: 55 kPa

Locate the horizontal line representing a flow rate of 6 m3/h (line A-A). The valve authority is given by the equation:

Where:

p1 = pressure drop across the fully open valve p2 = pressure drop across the rest of the circuit

with a full open valve

The ideal valve would give a pressure drop equal to the system pressure drop (i.e. an authority of

0.5): If p1 = p2

In this example an authority of 0.5 would be given by a valve having a pressure drop of 55 kPa at that flow rate (point B). The intersection of line A–A with a vertical line drawn from B lies between two diagonal lines; this means that no ideally-sized valve is available. The intersection of line A–A with the diagonal lines gives the pressure drops stated by real, rather than ideal, valves. In this case, a valve with kVS 6.3 would give a pressure drop of 90.7 kPa (point C):

The largest valve, with kVS 10, would give a pressure drop of 36 kPa (point D):

Generally, the smaller valve would be selected (resulting in a valve authority higher than 0.5 and therefore improved control). However, this will increase the total pressure and should be checked by the system designer for compatibility with available pump heads, etc. The ideal authority is 0.5 with a preferred range of between 0.4 and 0.7.

2 For fluids with specific gravity (S.G. )

different from 1

Design data:

Flow rate: 6 m3/h of fluid, S.G. 0.9 System pressure drop: 10 kPa

For this example, the left hand axis of the diagram must be ignored. Starting from the right hand axis, the flow rate of 6 m3/h is located (point E). The intersection of the diagonal line from point E with a vertical line from S.G. = 0.9 (point F) gives the starting point for the effective flow rate line G-G. The process then continues as for Example 1, so 10 kPa intersects G-G nearest to the kVS 16 diagonal. The intersection of G-G with kVS 16 gives a valve pressure drop of 12.7 kPa (point H).

Data sheet Two way valve VFS 2

Control valve sizing diagram for steam

Max. p in low pressure steam application variance from 0.5 bar to 6 bar (see page 2)

mass flow of saturated water steam (kg/h)

Critical Pressure Drop (kPa)

Absolute Inlet Pressure

Saturated Sream Temperature

Superheat °C

mass flow of superheated water steam (kg/h)

Steam valve sizing is based on 40 % of the absolute steam pressure (immediately upstream of the valve), being dropped across the valve when fully open. At this condition the steam is travelling at or close to its critical velocity

(approx. 300 m/s) and throttling will occur over the full valve stroke. If the steam is travelling slower than this then the first part of the valve stroke will merely increase the velocity of the steam without reducing the volumetric flow.

Data sheet Two way valve VFS 2

Control valve sizing diagram for steam

(continued)

1 For saturated steam

Design data:

Flow rate: 1000 kg/h Absolute inlet pressure: 5 bar (500 kPa)

- follow dashed line -

The absolute inlet pressure is 500 kPa. 40% of this is 200 kPa.

Locate the diagonal line corresponding to the pressure drop of 200 kPa (line A-A).

Read the absolute inlet pressure on the lower left hand scale (point B), and draw a horizontal line across until it meets the pressure drop diagonal (A-A) at point C.

From this point extend a vertical line upwards until it meets the horizontal line representing the steam flow of 1000 kg/h from point D. The intersection of this is point E.

The nearest diagonal kVS line above this is line F-F with a kVS of 25 (point E’). If the ideal valve size is not available the next largest size should be selected to ensure design flow.

The pressure drop through valve at the flow rate is found by the intersection of the 1000kg/h line with F-F (point E’) and dropping a vertical; this actually hits the horizontal line for 500 kPa (point E’’) inlet pressure at a pressure drop diagonal of 70 kPa. This is only 14 % of the inlet pressure and the control quality will not be good until the valve has partially closed. As with all steam valves this compromise is necessary since the next smaller valve would not pass the required flow (maximum flow would have been about 600 kg/h).

The maximum flow for same inlet pressure is found by extending the vertical line (C-E) through point E until it crosses the kVS 25 line F-F (point E’’’) and reading off the flow (1700 kg/h).

2 For superheated steam

Design data:

Flow rate: 500 kg/h Absolute inlet pressure: 5 bar (500 kPa) Steam temperature: 190 °C

The procedure for superheated steam is much the same as for saturated steam, but uses a different flow scale which slightly elevates the readings according to the degree of superheat.

- follow dotted line -

As before, the diagonal pressure drop line A-A is located as before for 40 % of 500 (200 kg/h). The horizontal inlet pressure line through point B is now extended to the left to read off the corresponding saturated steam temperature at point G (150 °C). The difference between the saturated steam temperature and the superheated steam temperature is 190 °C - 150 °C = 40 °C.

The superheated steam flow is found on the upper right hand scale, point H, and the diagonal line is followed down from here until it meets a vertical line from the steam temperature elevation (40 °C) at point J.

As before, the horizontal line through point B is drawn to cut line A-A at point C and the point where the vertical line from this point meets the horizontal line from point J is the operating point (point K). This horizontal line, J-K, is the corrected flow line. The nearest diagonal line above this is for kVS 10 (point K’). A vertical line the intersection of J-K with the 10 kVS line intersects the 500 kPa inlet pressure line (point K’’) at a pressure drop diagonal of about 150 kPa. This is about 30% of the inlet pressure which will give reasonable control quality (compared to recommended ratio of 40%).

dropped from

Data sheet Two way valve VFS 2

Dimensions

118 .5

Adapter

065Z7548

mi n. 150

min . 100

VFS 2 (DN 15-50) +

AMV(E) 25, 35 (SU/SD)

VFS 2 (DN 15-50) +

AMV(E) 56 +

clutch 065Z7551

L H H

k d

(number)

Valve weight

15 13 0 237 383 65 14 4 3.6

20 150 237 383 75 14 4 4.3

25 16 0 237 383 85 14 4 5.0

32 180 259 405 100 18 4 8.7

40 200 259 405 110 18 4 9.5

50 230 259 405 125 18 4 11. 7

mi n. 118

mi n. 150

min . 81

VFS 2 (DN 65-100) +

AMV(E) 55, 56

VFS 2 (DN 65-100) +

AMV(E) 65X

VFS 2 (DN 65-100) +

AMV(E) 85, 86

(kg)

L H

k d

n Valve weight

(number) (kg)

65 290 484 525 568 14 5 18 8 23.0

80 310 503 544 587 160 18 8 28 .1

100 350 530 571 614 19 0 22 8 40.7

Data sheet Two way valve VFS 2

Danfoss VFS 2 Data sheet

Specifications and Main Features

Frequently Asked Questions

User Manual