UK Product Handbook 2026 - Volume 1

44

Control systems Self-acting controls

Pressure/temperature limits

Pressure psi g

0

150

290

435

580

572

A

392

The product must not be used in this region.

Steam saturation curve

212

D

E

C

B

32

Pressure bar g

A - B Flanged EN 1092 PN40, ASME 300 and BS 10 Table H. A - C Flanged EN 1092 PN25 and ASME 150

A - D Flanged JIS/KS 10 A - E Flanged JIS/KS 20

Body design conditions

PN40

Maximum design pressure

40 bar g @ 20 °C

580 psi g @ 68 °F

4.5 34

Maximum design temperature

300 °C @ 25.8 bar g

572 F @ 374 psi g

Minimum design temperature

-10 °C

14 °F

A - B A - C A - D

300 °C @ 25.8 bar g

572 °F @ 374 psi g

300 °C @ 10.0 bar g

572 °F @ 145 psi g

Maximum operating temperature

300 °C @ 10 bar g

572 °F @ 145 psi g

A - E

300 °C @ 25.8 bar g

572 °F @ 374 psi g

Minimum operating temperature Note : For lower operating temperatures consult Spirax Sarco

0 °C

DN15 (½") 17.0 (247)

DN20 (¾") 10.0 (145)

DN25 (1")

DN32 (1¼")

DN40 (1½")

DN50 (2")

Size

4.5 (65)

3.0 (44)

2.0 (29)

1.5 (22)

KA43

Maximum differential pressure bar

10.0 (145)

9.0 (131) 16.0 (232)

8.2 (119) 16.0 (232)

6.9 (100) 13.8 (200)

KB43

KC43

24 bar g (348 psi g)

Designed for a maximum cold hydraulic test pressure of:

Kv values Size

DN15 (½")

DN20 (¾")

DN25 (1")

DN32 (1¼")

DN40 (1½")

DN50 (2")

For conversion: Cv (UK) = Kv x 0.963 Cv (US) = Kv x 1.156

KA43

2.90

4.64

9.80

16.48

23.70

34.00

KB43

-

-

9.80

16.48

23.70

34.00

KC43

-

-

-

16.48

16.48

34.00

Capacities For saturated steam sizing capacities see TI-GCM-08. For water valve sizing capacities see TI-GCM-09.

TI-P078-06 CTLS Issue 9

Page 2 of 5

KA43, KB43 and KC43 Steel Self-acting Control Valves

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