1

2

3

4

5

6

12

29

10

11

21

15

14

18

4.6.83

20

25

24

Materials

No. Part

1

Adjustment screw

2

Adjustment lock-nut

3

'C' washer

4

Spring housing

5

Top spring plate

Pressure adjustment

6

spring

DN15 to DN50

7

Bottom spring plate

Spring

Securing nuts

Cast steel

23

Main

Securing nuts Steel

diaphragm Securing bolts Steel

DIN 17245 GS C25

BS 3692 Gr.8

8

housing

Securing studs

9

Pilot diaphragm

DN15

DN25

DN40

DN80

and

and

and

BS 4882 Gr. 2H

M12 x 50 mm

M12 x 60 mm

M12 x 65 mm

M12 x 80 mm

BS 1449 316 S31

BS 970 431 S29

BS 970 431 S29

BS 3605 304 S14

BS 3692 Gr. 8

BS 4439 Gr. 8.8

BS 3692 Gr. 2H

DIN 17245 GS C25

10 Pilot valve housing

11 Pilot valve plunger

12 Spring housing cover

13 Pilot valve and seat unit

14 Internal strainer

15 Body gasket

16 Main valve return spring

17 Main valve

18 Main valve seat

reinforced

24 Main diaphragms

Stainless steel

25 Main diaphragm plate

Stainless steel

26 Pushrod

Stainless steel

27 Control pipe assembly

Stainless steel

28 Plug "BSP

Steel

29 Pressure pipe union

Steel

30 Lock-nut

Steel

45

Body studs

Steel

Body nuts M12 x 40 mm Steel

Control valves

Pressure reducing/surplussing valves

8

13

7

9

17

16

Material

Steel

Steel

Stainless steel

Cast steel

Steel

Stainless steel

Steel

Steel

Steel

DN15 to DN80

Stainless steel

Steel

Stainless steel

Stainless steel

Stainless steel

Stainless steel

No. Part

20 Main valve body

21

Pilot valve Securing nuts

housing

Securing studs

22 Main diaphragm chamber

Material

Cast steel

Steel

Steel

DN15 and

DN25 to

DN80

DIN 17245 GS C25

BS 3692 Gr. 8

Stainless steel

exfoliated graphite

Stainless steel

Stainless steel

Stainless steel

BS 2056 302 S25

BS 970 431 S29

BS 970 431 S29

46

Upper main

diaphragm chamber

Cast steel

13

16

17

26

27

30

23

22

28

BS 3692 Gr. 8.8

BS 3692 Gr. 8

BS 1449 304 S16

DIN 17245 GS C25

BS 970 220 Mo7

BS 2056302 S25

BS 970 220 Mo7

BS 3692 Gr. 8

BS 4439 Gr. 8.8

M10 x 30 mm

BS 1449 316 S31

DIN 17245 GS C25

GP 240 GH + N

BS 970 431 S29

BS 1449 304 S12

BS 970 431 S29

BS 1449 304 S16

45

46

Page 2 of 7

SDP143 Pilot Operated Pressure Surplussing Valve with Cast Steel Body

TI-P004-01 CH Issue 6

Page 2 of 7

Arrangement of main valve

assembly as used in sizes

DN40 and DN50.

DN80

DN20

DN50

BS 4439 Gr. 8.8

M10 x 25 mm

M12 x 30 mm

M12 x 40 mm

DN20

DN32

DN50