The Original Seat Valve
SRC Sanitary Remote-Controlled Valve
SRC valve with valve body combination 21.

Application

SRC is an air-operated seat valve in a sanitary and flexible design giving a wide field of application, e.g. as a stop valve with two or three ports or as change-over valve with three to five ports

Working principle

The valve is remote-controlled by means of compressed air. It has few and simple moveable parts which results in a very reliable valve.

Standard Design

SRC consists of actuator, lip seal, plug and valve bodies. All components are assembled by means of clamp rings and a stem clip-system. For sizes DN125 and DN150, the piston and valve plug are screwed together. In order to facilitate installation the valve is only partly assembled when delivered. The valve has welding ends as standard.

SRC, sizes DN125 and DN150 are very heavy. Therefore it is recommended to manufacture and use auxiliary handling equipment. Guidelines are given in IM 70007. The recommended auxiliary equipment cannot be supplied by Alfa Laval.

Actuator function

  • - Pneumatic downward movement, spring return (NO).
  • - Pneumatic upward and downward movement (A/A) sizes 25-101.6mm/DN25-100.
  • - Actuator for intermediate position of the valve plug as option sizes 25-101.6mm/DN25-100.
  • - Actuator for intermediate position of the valve plug as option sizes 25-101.6mm/DN25-100.

Other valves in the same basic design:

  • - Aseptic Manual and Remote controlled valve, type ARC/AMO.
  • - Sanitary Long Stroke valve, type SRC-LS.
  • - Sanitary Manual valves, type SMO/SMO-R.
  • - Sanitary Reverse Closing valve, type SRC-RC.

Valve body combinations


 

20 30 21 22 31 32

Pressure drop/capacity diagrams

Stop valve   Stop valve
 
Change-over valve   Change-over valve
 
 

NOTE!

For the diagrams the following applies:
Medium: Water (20°C).
Measurement: In accordance with VDI 2173

Pressure data for SRC

Actuator type / function
10. Pneumatic downward movement, spring return (NO-lower seat)
20. Pneumatic upward movement, spring return (NC-lower seat)
30. Pneumatic upward and downward movement (A/A), (not sizes DN125 and DN150).
60. Three-positions (NO-lower seat) (not sizes DN125 and DN150)
70. Three-positions (NC-lower seat) (not sizes DN125 and DN150).

Table 1: Stop and change-over valves - Max. pressure without leakage at the valve seat
Actuator / Valve body
combination and direction
of pressure		 Air
pressure (bar)		 Actuator
type/
function		 Valve Size
Type DN25
25 mm		 DN40
38 mm		 DN50
51mm		 DN65
63.5mm		 76.1mm DN80 DN100
101,6 mm		 DN 125-150
                     
  10(NO)   9.5 4.5 4.5 3.0 5.0 5.0 3.5 5.2
  60(NO)   9.5 4.5 4.5 3.0 5.0 5.0 3.5 5.2
5 10(NO) ISO Min.10 7.0 4.0 3.0 4.0 3.2 2.5 8.7
5 DIN Min.10 6.0 3.6 3.0 4.0 3.2 2.5 8.7
6 10(NO) ISO Min.10 10.0 5.5 4.0 6.0 4.8 4.0 4.4
6   DIN Min.10 8.5 5.0 4.0 6.0 4.8 4.0 4.4
5 20(NC)   9.5 4.5 4.5 3.0 4.5 4.5 2.5 8.1*
6 70(NC)   Min.10 6.5 6.5 4.0 7.0 7.0 4.0 3.7
  20(NC) ISO Min.10 7.0 4.0 2.5 5.0 4.0 3.5 5.2
  70(NC) DIN Min.10 6.0 3.6 2.5 5.0 4.0 3.5 5.2
5     Min.10 9.0 9.0 8.0 Min.10 Min.10 7.5  
  30(A/A)                  
6     Min.10 Min.10 Min.10 9.0 Min.10 Min.10 9.0  
5   ISO Min.10 10.0 9.0 6.0 Min.10 8.0 7.5  
5 30(A/A) DIN Min.10 8.5 8.2 6.0 Min.10 8.0 7.5  
6 ISO Min.10 Min.10 Min.10 7.0 Min.10 9.4 9.0  
6   DIN Min.10 9.1 8.5 7.0 10 9.4 9.0  
AC = Air closes
SC = Spring closes
A = Air
* = Values are valid for 8 bar air pressure
= Actual product pressure

Pressure data for SRC

Table 2: Stop and change-over valves. The table shows the approx. static pressure (P) in bar against which the valve can open.
Actuator / Valve body
combination and direction of pressure		 Air
pressure (bar)		 Actuator
type/
function		 Type Valve size
DN25
25 mm		 DN40
38 mm		 DN50
51mm		 DN65 63.5mm 76.1mm DN80 DN100
101.6 mm		 DN
125-150
  10(NO) ISO Min.10 9.0 6.0 4.0 7.5 6.5 5.0 8.8
  60(NO) DIN Min.10 7.7 5.5 4.0 7.5 6.5 5.0 8.8
6 10(NO)   Min.10 7.5 7.5 5.5 9.0 7.5 6.0 8.1
6 60(NO)   Min.10 7.5 7.5 5.5 9.0 7.5 6.0 min. 10**
6 20(NC) ISO Min.10 10.0 7.5 5.0 9.0 7.5 6.0 7.8
6 70(NC) DIN Min.10 8.5 6.8 5.0 9.0 7.5 6.0 7.8
  20(NC)   Min.10 6.0 6.0 5.0 7.5 6.5 5.0 8.9
  70(NC)   Min.10 6.0 6.0 5.0 7.5 6.5 5.0 8.9
AO = Air opens
SO = Spring opens
Table 3: Stop and change-over valves with extra strong springs or special cylinder (not for sizes DN125-150) - Max. pressure without leakage at the valve seat
    Extra strong spring
Valve size in DN		 Spec. actuator
(dia. 133 mm)
Valve size in DN
Actuator / Valve body
combination and direction of pressure		 Air
pressure (bar)		 Actuator
type/
function		 Type DN40
38 mm		 DN50
51mm		 DN65 63.5mm 76.1mm DN80 DN100 101.6 mm 40
38
mm		 50
51
mm		 65
63.5
mm
  10(NO)   6.5 6.5 4.0 7.0 7.0 4.5 9.0 9.0 6.0
  60(NO)                    
5   ISO 2.0 0.0 0.0 0.0 0.0 0.0 10.0 8.5 6.0
5 10(NO) DIN 1.7 0.0 0.0 0.0 0.0 0.0 8.5 7.7 6.0
6 60(NO) ISO 2.0 2.0 1.0 1.0 1.0 1.0 * * *
6   DIN 1.7 1.8 1.0 1.0 1.0 1.0 * * *
5 20(NC)   0.0 0.0 0.0 0.0 0.0 0.0 9.0 9.0 6.0
6 70(NC)   2.0 2.0 1.0 1.0 1.0 1.0 * * *
  20(NC) ISO 9.0 5.5 3.5 7.0 5.0 4.5 10.0 9.0 6.0
  70(NC) DIN 7.7 5.0 3.5 7.0 5.0 4.5 8.5 8.2 6.0
AC = Air closes
SC = Spring closes
A = Air
P = Product
**= Values are valid for air pressure of 8 bar.
* = Do not exceed 5 bar air pressure.
Dimensions (mm)
Nominal size Inch
DN/OD		 DIN
DN
25 38 51 63.5 76.1 101.6 25 40 50 65 80 100 125 150
                        NC NO NC NO
A1 311 345 355 389 455 527 311 343 354 386 456 526 571 573 584 586
A2 332 370 380 414 487 559 332 368 379 411 488 558 614 618 627 631
A3 365 416 449 500 584 677 365 414 448 497 585 676 740 737 777 775
A4 387 441 474 525 616 709 387 439 473 522 617 708 781 778 818 816
C 55.6 79 94 113 129 163 55.6 79 94 113 129 160 167 167 192 192
OD 25.2 38.1 50.8 63.5 76.1 101.6 29 41 53 70 85 104 129 129 154 154
ID 22.2 34.9 47.6 60.3 72.1 97.6 26 38 50 66 81 100 125 125 150 150
t 1.5 1.6 1.6 1.6 2.0 2.0 1.5 1.5 1.5 2.0 2.0 2.0 2.0 2.0 2.0 2.0
E1 30.1 49.5 62 82 87 134 32 49.5 62 82 87 134 150 150 150 150
E2 57 49.5 62 82 87 134 57 49.5 62 82 87 134 150 150 150 150
F1 21 25 25 25 32 32 21 25 25 25 32 32 43 45 43 45
F2 20 25 25 25 32 32 20 25 25 25 32 32 41 41 41 41
H 87 87 87 87 133 133 87 87 87 87 133 133 199 199 199 199
M/ISO clamp 21 21 21 21 21 21                    
M/DIN clamp             21 21 21 21 21 21        
M/ISO male 21 21 21 21 21 21                    
M/DIN male             22 22 23 25 25 30 46 46 50 50
M/SMS male 20 20 20 24 24 35                    
M/BS male 22 22 22 22 22 27                    
Weight (kg)
Stop valve:		 5.0 4.9 5.0 5.4 12.4 13.0 5.0 4.9 5.0 5.4 12.4 13.0 40.3 40.3 40.9 40.9
Change-over valve: 5.8 5.9 6.1 6.8 14.6 15.9 5.8 5.9 6.1 6.8 14.6 15.9 50 50 51.3 51.3
a. Stop valve. b. Change-over valve. Caution, opening/closing time:

    Opening/closing time will be affected by the following

  • - The air supply (air pressure).
  • - The length and dimensions of the air hoses.
  • - Number of valves connected to the same air hose.
  • - Use of single solenoid valve for serial connected air actuator functions.
  • - Product pressure.

Air Connections Compressed air:
R 1/8" (BSP), internal thread.
Fig 2. Dimensions.

Technical data

Max. product pressure: 1000 kPa (10 bar).
Min. product pressure: Full vacuum.
Temperature range, standard lip seal: -10°C to +100°C (EPDM)
Temperature range, special lip seal: -10°C to +140°C (EPDM)

Air pressure, actuator

- Sizes 25-101.6mm /DN25-100 500 to 700 kPa (5 to 7 bar)
- Sizes DN125-150 600 to 800 kPa (6 to 8 bar)
Air consumption (litres free air) for one stroke
Size 25-63.5 mm
DN 25-65		 76-101.6 mm
DN 80-100		 DN 125-150 DN 125-150
 
Stop valve/ Change-over valve Actuator function 0.2 x Air pressure (bar) 0.7 x Air pressure (bar) 1.5 x Air pressure (bar) 2.2 x Air pressure (bar)
 
NO and NC NO and NC NC NO
Stop valve/ Change-over valve Actuator function 0.4 x Air pressure (bar) 1.3 x Air pressure (bar) 3.6 x Air pressure (bar) 2.9 x Air pressure (bar)
 
A/A A/A NC (Support air for closing) NO (Support air for opening)

Materials

Product wetted steel parts: Acid-resistant steel 1.4401 (316L).
Finish: Semi bright.
Other steel parts: Stainless steel 1.4301 (304).

Plug stem

 
- Sizes 25-101.6 mm/DN25-100 1.4401 (316L) with hard chrome plated stem surface
- Sizes DN125-150 1.4401 (316L)
Product wetted seals EPDM (standard)
Other seals Nitrile (NBR)
Alternative product wetted seals Nitrile (NBR) and Fluorinated rubber (FPM), PTFE/FEP
 

Options

  • - Male parts or clamp ends in accordance with required standard.
  • - Control and Indication (see chapter in Product Catalogue).
  • - Damper against water hammer applicable for sizes 25 - 101.6 mm/DN25 - 100.
  • - Actuator with stronger spring applicable for sizes 38 - 101.6 mm/DN40 - 100 .
  • - Larger actuator for valve sizes 38-51mm, DN 40-65.
  • - Stainless steel seal disc replacing standard lip seal.
  • - Two-step or three-position actuator applicable for sizes 25 - 101.6 mm/DN25 - 100
  • - Tangential side port valve.
  • - Surface roughness, product wetted parts: Ra ⋜0.8 µm.
  • - Product wetted seals of Nitrile (NBR), Fluorinated rubber (FPM) or PTFE.
  • - Service tools for actuator.

Ordering

Please state the following when ordering:

  • - Size.
  • - Connections if not welding ends.
  • - Valve body combination.
  • - Actuator function, NC, NO or A/A, A/A for sizes 25 - 101,6 mm/DN25 - 100.
  • - Options.

This product has EHEDG certification