Seetru Limited

Seetru are Bristol-based manufacturers of safety relief and other special purpose ancillary valves fora wide range of compressed air, industrial gas, refrigerants, powder, steam, liquid and liquefied gas
applications. Seetru change-over valves offer increased plant and process efficiency.

SEETRU

Seetru liquid level gauges are primarily of two types, sight gauges and magnetic float bypass gauges.
Many of the gauges are direct reading though most have optional electronic remote reading systems
and computer interfaces.

Seetru Safety Relief Valves
For Hydrogen Applications

HYDROGEN

SeetruLimited

That’s Safety!

Edition 4 (18.1.2024)

Seetru Limited
Solution for the Hydrogen Industry

Safety Relief Valves and Change Over Valves
Suitable for the following applications:••••Hydrogen generation - electrolyser
Hydrogen fuel cells
Hydrogen compressors and pumps
Hydrogen fuelling systems•••

Hydrogen storage
Pressure vessels,receivers and piping systems containing hydrogen
Hydrogen transportation

The Seetru range of safety valves for compressed air and gas are compact, highly efficient and incorporate the exclusive
Tutchtite– seal technology for repeatable bubble-tight sealing performance: designed for applications including air/gas
compressors, specialist gas plants, chemical equipment and piping, pressure vessels, thermal relief and medical gases etc.
These valves meet important international standards which include: ISO-4126-1 & -7 and ASME BPVC VIII.1 & XIII design codes
as well as type test approvals from TÜV and the National Board. These products comply with the requirements of the European
Pressure Equipment Directive (PED) and are available with both the CE mark as well as the UV stamp, and have wide international
approvals such as the EAC (TR CU) customs union certification and declaration and the Canadian CRN. Seetru products are fullycompliant with the requirements of the UK Pressure Equipment (Safety) Regulations and come with the UKCA mark.

Change-over valves (sometimes referred to as selector valves or three-way valves) enables the switching of flow fromone safety valve to another. Typically used where plant shutdown is impossible or undesirable for process, engineeringor commercial reasons. With change-over valves it is possible to switch over between parallel safety valves without
interrupting operation, so that maintenance work can be carried out on each safety valve in turn. Seetru change-over valvesin combination with our safety valves provide the best solution for plant safety and efficiency. Seetru products are widely
recognised for their exceptional quality and reliability.

SeetruLimited

That’s Safety!

www.seetru.com | info@seetru.com | +44 (0) 117 930 6100

Table of contents
Type

Product / Design

Materials

Inlet Connections

Pressure RangePage

636/656/646

Enclosed Discharge

Bronze Or Stainless Steel

3/8" To 2" Bsp, Bspt Or Npt

0.32 To 55.2 bar

4-9

Enclosed Discharge

Bronze Stainless Steel1/2” To 2” Bsp, Bspt Or Npt

0.3 To 28.0 bar

10-15

Threaded Connections

Metal To Metal Sealing

33020/
34020/
34320

Enclosed Discharge

Brass Or Stainless Steel

3/8" To 1/2" Bsp, Bspt Or Npt

55.0 To 103.4 bar

16-18

33110/
34110/
34410

Enclosed Discharge

Brass Or Stainless Steel

3/8" To 1/2" Bsp, Bspt Or Npt

27 To 241.3 bar

19-21

329

Enclosed Discharge

Bronze Or Stainless Steel3/8” To 3/4” Bsp, Bspt Or Npt

53.0 To 370.0 bar

22-24

Type 359 /B4605 / B6605

Enclosed Discharge
Safety Relief Valves

Stainless Steel Construction
With Metal Ball Sealing

Inlet Connections From 3/8" To
1/2" Bsp, Bspt Or Npt

35.0 To 500.0 bar

25-27

Type
94605 / 946H5 /95605 / 956H5

Enclosed Discharge
Safety Relief Valves

Stainless Steel◦ ½” Npt, Bsp & Bspt
◦ 9/16” Cone & Thread◦ 3/4” Cone & Thread◦ 35.0 To 515 bar (9*605)◦ 35.0 To 1100 bar (9*6h5)

28-30

Stainless Steel

Dn20 (3/4”) Or Dn25 (1”) Din
Or Ansi Flanges

0.3 To 28.0 bar

31-33

Stainless Steel

Dn20 (3/4”) Or Dn25 (1”) Din
Or Ansi Flanges

0.32 To 49.0 bar

34-36

936/946

Enclosed Discharge
946 FLANGED
Flanged Connections
Enclosed Discharge
646 FLANGED
Flanged Connections

COV10

Change Over Valve

Stainless steel construction
with PTFE

Suitable for Safety Relief Valves
with up to 10mm bore
(Full Lift Type)For Safety valves with setpressure up to 75.0 bar

37-39

COV13

Change Over Valve

Stainless steel construction
with PTFE or Elastomer sealing

Suitable for Safety Relief Valves
with up to 10mm bore
(Full Lift Type)For Safety valves with setpressure up to 65.0 bar

37-39

COV30

Change Over Valve

Stainless steel construction
with PTFE sealing

Suitable for Safety Relief Valves
with up to 18mm bore
(Full Lift Type)For Safety valves with setpressure up to 100.0 bar

37-39

SeetruLimited

That’s Safety!

www.seetru.com | info@seetru.com | +44 (0) 117 930 6100

Enclosed Discharge Safety Relief Valves
for compressed Air & Gas

Seetru LimitedhydrogenType 636 / 631

Safety valves with bronze body <Enclosed discharge valve with threaded connections <Example Applications
•
•
•
•
•

Air / gas compressors
Pressure vessels
Pneumatic systems
Medical gases
Technical gases

Specifications

Approvals•

Inlet connections: 3/8” to 2” (depending on bore size)•

Temperature: -40°C to +200°C (depending on seal material)•

Pressure range: 0.32 to 55.2 bar (depending on bore size)

•
•
•
•
•
•

Materials of Construction
Component

Material

Grade

Inlet

Brass

CW614N

Stainless Steel1.4401 (316)BronzeCC491K
SB-62 C83600

Body
Internal parts

Spring

Brass

CW614N

Stainless Steel1.4401 (316)

Stainless Steel

1.4310 (302)

Designed in accordance with BS EN ISO-4126-1 & -7
PED 2014/68/EU (CE)PE(S)R UK SI 2016 No. 1105 (UKCA)
ASME BPVC VIII.1 & XIII (UV)
CRN
EAC

Seal Materials
Seal Material

Temperature Range

Viton® (FKM)-15°C to +200°C

Nitrile (NBR)-40°C to +120°C

Standard seal materials shown, others are available.

Easing Gear / Lifting Gear Options•
Standard option:Rota-lift, twist type(not gas tight)•

Other Options:

Sealed Cap (gas tight cap)

SeetruLimited

That’s Safety!

Unsealed lever (not gas tight)

Sealed lever (gas tight)

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Page
Page404

Technical information by bore size
Bore size

9.5/10mm

Inlet Size

3/8"

13.7mm1/2"

Outlet Size

3/4"

Flow Area

70.9mm²

3/4"

1/2"

(above 1.55 bar)

3/4"

17mm
1"

1"

20mm

1 1/4"

1 1/2"

1"

1 1/4"

25mm
1 1/2"

1 1/4"

1 1/2"

1"

1 1/2"

2"

2"

147.7mm²

227mm²314mm²490.4mm²

H - Height (Rota-lift cap version)

102mm (up to 33 bar)
116mm (33-55.2 bar)

143mm (up to 35 bar)172.5mm (35-49 bar)

204mm

227mm

252mm

TÜV alloted outflow coefficient

0.77 above 1.55 bar

0.77

0.77

0.77

0.77

NB Certified rated slope (ASME)

1.74 scfm/psia

3.47 scfm/psia

5.60 scfm/psia

7.77 scfm/psia

12.26 scfm/psia

0.8

1.1

3.6

4.0

5.1

Set Pressure range - PED (CE) bar

0.48 to 55.2

0.32 to 49.0

1.0 to 35.0

3.0 to 35.0

5.65 to 30.0

Set Pressure range - ASME (UV) psi

22.5 to 800.4

20.3 to 710.5

34.8 to 507.5

43.5 to 507.5

82.0 to 435.0

Weight (approximate) Kg

Relieving pressure/fully open pressure2"

Set Pressure +10%

Reseating pressure

Set Pressure -10% (0.3 bar minimum)

Maximum permissible built up back pressure = 10% of set pressure at or below which flow is not reduced.
Stable operation on flows down to 50% of valve rated capacity.

Valves with Rota-lift Easing Gear

Standard Thread Connection Types•

BSP Parallel male thread•

BSP Taper male thread•

NPT male threadStandard Outlet Connection Types•

BSP Parallel female thread•

NPT female thread

H

Valve Selection Guide
Approval
Required

Valve type

INLET THREAD

Select Bore

Inlet SizeThread Type

OutletThread TypeEasing Gear

Seal Material
Viton® (FKM)

636 (Brass inlet)
PED (CE)
656(St. Steel inlet

PED (CE), ASME
(UV) & CR

Select bore size
from above table

Select inlet size
from above table

Select Inlet
thread type

Select Outlet
thread type

Select easinggear/top fitting

Nitrile (NRB)

631 (Brass inlet)
651(St. Steel inlet

Other

EAC marking available upon request*Please send your selected details to Seetru and we can provide the full ordering code, price and lead-time.

Example of Valve Selection Process
ExampleSelection

CE/PED

636

20

1 1/2"

BSP Taper

BSP parallel

Rota-lift

Viton

10.5 barApproval

Valve Type

Bore = 20mm

Inlet Size

Inlet Thread
Type

Outlet Thread
Type

Easing Gear

Seal

Set Pressure

SeetruLimited

That’s Safety!

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Page
Page41
5

Capacity Table - In accordance with TÜV, AIR at 0°C and 1013mbar. Normal m³/hour
Type 636/656: Flow rates at 10% above the set pressure
Bore Size (D0)

Set Pressure

9.5mm

bar

psi

0.32

4.64

Nm³/Hour

13.7mm

17mm

20mm

25mm

Nm³/HourNm³/HourNm³/HourNm³/Hour

123.9

0.48

6.96

51.5

138.2

1

14.5

79.1

178.9

251.6

2

29

119.4

248.4

385.5

3

43.5

160.4

333.5

513.5

710.7

4

58

201.2

418.5

644.4

891.9

5

72.5

242.1

503.6

775.4

1073.2

5.65

81.93

268.7

558.8

860.5

1191.01860.9

6

87

283.0

588.6

906.3

1254.5

1960.1

7

101.5

323.9

673.6

1037.31435.72243.3

8

116

364.8

758.7

1168.21616.92526.5

9

130.5

405.7

843.7

1299.21798.22809.7

10

145

446.6

928.8

1430.2

1979.43092.9

15

217.5

651.1

1354.02084.92885.74508.9

20

290

855.6

1779.32739.73791.95924.925

362.5

1060.02204.53394.44698.27340.9304351264.52629.74049.25604.48756.94703.96510.735507.5

1468.93054.940

580

1673.43480.245

652.5

1877.93905.449

710.5

2041.54245.650725

2082.4

55.2

800.4

2295.0For any intermediate pressures/flows please contact Seetru

Capacity Table - In accordance with ASME BPVC.XIII, AIR at 60°F and 14.7 psia/scfm. SCFM
Type 631/651: Flow rates at 10% above the set pressure
Bore Size (D0)

Set Pressure

9.5mm

psi

bar

20.3

1.40

SCFM

13.7mm

17mm

20mm

25mm

SCFM

SCFM

SCFM

SCFM

131.9

22.5

2.50

68.7

139.4

30

2.07

81.5

165.5

34.8

2.80

90.6

183.8

296.7

40

2.76

100.4

203.7

328.7

43.5

3.00

106.9

217.0

350.2

486.0

50

3.45

119.2

241.8

390.3

541.5

82

5.66

179.3

363.9

587.3

814.9

1285.8

100

6.90

213.2

432.6

698.1

968.7

1528.4

150

10.34

307.2

623.4

1006.11395.92202.6

200

13.79

401.2

814.2

1314.01823.22876.8

250

17.24

495.3

1005.01621.92250.43550.8

300

20.69

589.3

1195.8

1929.82677.64224.9

350

24.14

683.3

1386.62237.83104.94899.1

400

27.59

777.4

1577.42545.73532.25573.36045.2

435

30.00

843.2

1711.02761.23831.2

450

31.03

871.4

1768.22853.63959.3

500

34.48

965.4

1959.03161.54386.6

507.5

35.00

979.5

1987.63207.74450.7550

37.93

1059.42149.8600

41.38

1153.42340.665044.83

1247.52531.4700

48.28

1341.52722.22762.3

710.5

49.00

1361.3750

51.72

1435.5

800.4

55.20

1530.3For any intermediate pressures/flows please contact Seetru

SeetruLimited

That’s Safety!

RETURN TO CONTENTS PAGE

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Page
Page426

Enclosed Discharge Safety Relief Valves
for compressed Air & Gas

Seetru LimitedhydrogenType 646 / 641

Safety valves with Stainless Steel body <Enclosed discharge valve with threaded connections <Example Applications
•
•
•
•
•

Air / gas compressors
Pressure vessels
Pneumatic systems
Medical gases
Technical gases

Specifications

Approvals•

Inlet connections: 3/8” to 2” (depending on bore size)•

Temperature: -40°C to +200°C (depending on seal material)•

Pressure range: 0.32 to 55.2 bar (depending on bore size)

•
•
•
•
•
•

Designed in accordance with BS EN ISO-4126-1 & -7
PED 2014/68/EU (CE)PE(S)R UK SI 2016 No. 1105 (UKCA)
ASME BPVC VIII.1 & XIII (UV)CRN
EAC

Materials of Construction
Component

Material

Grade

Inlet

Stainless Steel1.4401 (316)

Body

Stainless Steel1.4408 (316)Internal Parts

Stainless Steel1.4401 (316)

SpringStainless Steel

1.4310 (302)

Seal Materials
Seal Material

Temperature Range

Viton® (FKM)-15°C to +200°C

Nitrile (NBR)-40°C to +120°C

Standard seal materials shown, others are available.

Easing Gear / Lifting Gear Options•

Standard option: Rota-lift cap, twist type (not gas tight)•

Other Options:

Sealed Cap (gas tight cap)

SeetruLimited

That’s Safety!

Sealed lever (gas tight)

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Page
Page437

Technical information by bore size
Bore size

9.5/10mm

Inlet Size

3/8"

13.7mm1/2"

Outlet Size

3/4"

Flow Area

70.9mm²

3/4"

1/2"

(above 1.55 bar)

3/4"

17mm
1"

1"

20mm

1 1/4"

1 1/2"

1"

1 1/4"

25mm
1 1/2"

1 1/4"

1 1/2"

1"

1 1/2"

2"

2"

147.7mm²

227mm²314mm²490.4mm²

H - Height (Rota-lift cap version)

116mm

143mm (up to 35 bar)172.5mm (35-49 bar)

211mm

227mm

252mm

TÜV alloted outflow coefficient

0.77 above 1.55 bar

0.77

0.77

0.77

0.77

NB Certified rated slope (ASME)

1.74 scfm/psia

3.47 scfm/psia

5.60 scfm/psia

7.77 scfm/psia

12.26 scfm/psia

0.8

1.1

3.6

4.0

5.1

Set Pressure range - PED (CE) bar

0.48 to 55.2

0.32 to 49.0

1.0 to 35.0

3.0 to 35.0

5.65 to 30.0

Set Pressure range - ASME (UV) psi

22.5 to 800.4

20.3 to 710.5

34.8 to 507.5

43.5 to 507.5

82.0 to 435.0

Weight (approximate) Kg

Relieving pressure/fully open pressure

Set Pressure +10%

Reseating pressure

Set Pressure -10%

2"

Maximum permissible built up back pressure = 10% of set pressure at or below which flow is not reduced.
Stable operation on flows down to 50% of valve rated capacity.

Valves with Rota-lift Easing Gear

Standard Thread Connection Types•

BSP Parallel male thread•

BSP Taper male thread•

NPT male threadStandard Outlet Connection Types•

BSP Parallel female thread•

NPT female thread

H

INLET THREAD

Valve Selection Guide
Approval
Required

Valve type

PED (CE)

646

PED (CE), ASME
(UV) & CRN

Select Bore

Inlet Size

Inlet Thread
Type

Outlet Thread
Type

Easing Gear

Select bore size
from above table

Select inlet size
from above table

Select Inlet
thread type

Select Outlet
thread type

Select easinggear/top fitting

Seal Material
Viton® (FKM)

641

Nitrile (NRB)Other

EAC marking available upon request*Please send your selected details to Seetru and we can provide the full ordering code, price and lead-time.

Example of Valve Selection Process
ExampleSelection

PED, ASME &
CRN

641

20

1 1/2"

BSP Taper

BSP parallel

Rota-lift

Viton

10.5 barApproval

Valve Type

Bore = 20mm

Inlet Size

Inlet Thread
Type

Outlet Thread
Type

Easing Gear

Seal

Set Pressure

SeetruLimited

That’s Safety!

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Page
Page448

Capacity Table - In accordance with TÜV, AIR at 0°C and 1013mbar. Normal m³/hour
Type 646: Flow rates at 10% above the set pressure
Bore Size (D0)

Set Pressure
bar

psi

0.32

4.64

0.48

6.96

9.5mm

13.7mm

17mm

20mm

25mm

Nm³/HourNm³/HourNm³/HourNm³/HourNm³/Hour

51.5

138.2

123.9

1

14.5

79.1

178.9

251.6

2

29

119.4

248.4

385.5

3

43.5

160.4

333.5

513.5

710.7

4

58

201.2

418.5

644.4

891.9

5

72.5

242.1

503.6

775.4

1073.2

5.65

81.93

268.7

558.8

860.5

1191.01860.9

6

87

283.0

588.6

906.3

1254.5

1960.1

7

101.5

323.9

673.6

1037.31435.72243.3

8

116

364.8

758.7

1168.21616.92526.5

9

130.5

405.7

843.7

1299.21798.22809.7

10

145

446.6

928.8

1430.2

1979.43092.9

15

217.5

651.1

1354.02084.92885.74508.9

20

290

855.6

1779.32739.73791.95924.925

362.5

1060.02204.53394.44698.27340.9304351264.52629.74049.25604.48756.94703.96510.735507.5

1468.93054.940

580

1673.43480.245

652.5

1877.93905.449

710.5

2041.54245.650725

2082.4

55.2

800.4

2295.0For any intermediate pressures/flows please contact Seetru

Capacity Table - In accordance with ASME BPVC.XIII, AIR at 60°F and 14.7 psia/scfm. SCFM
Type 641: Flow rates at 10% above the set pressure
Bore Size (D0)

Set Pressure

9.5mm

psi

bar

20.3

1.40

SCFM

13.7mm

17mm

20mm

25mm

SCFM

SCFM

SCFM

SCFM

131.9

22.5

2.50

68.7

139.4

30

2.07

81.5

165.5

34.8

2.80

90.6

183.8

296.7

40

2.76

100.4

203.7

328.7

43.5

3.00

106.9

217.0

350.2

486.0

50

3.45

119.2

241.8

390.3

541.5

82

5.66

179.3

363.9

587.3

814.9

1285.8

100

6.90

213.2

432.6

698.1

968.7

1528.4

150

10.34

307.2

623.4

1006.11395.92202.6

200

13.79

401.2

814.2

1314.01823.22876.8

250

17.24

495.3

1005.01621.92250.43550.8

300

20.69

589.3

1195.8

1929.82677.64224.9

350

24.14

683.3

1386.62237.83104.94899.1

400

27.59

777.4

1577.42545.73532.25573.36045.2

435

30.00

843.2

1711.02761.23831.2

450

31.03

871.4

1768.22853.63959.3

500

34.48

965.4

1959.03161.54386.6

507.5

35.00

979.5

1987.63207.74450.7550

37.93

1059.42149.8600

41.38

1153.42340.665044.83

1247.52531.4700

48.28

1341.52722.22762.3

710.5

49.00

1361.3750

51.72

1435.5

800.4

55.20

1530.3For any intermediate pressures/flows please contact Seetru

SeetruLimited

That’s Safety!

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Page
Page459

Enclosed Discharge Safety Relief Valves
for compressed air or gases

steam

cryogenics & liquefied gases

Seetru Limitedhydrogen

Safety valves made with brass inlets<
Enclosed discharge valve with threaded connections<
Metal to metal sealing<

Type 936 Threaded
Example Applications
•
•
•
•
•

Air / gas compressors
Pressure vessels
Medical gases/Technical gases
Thermal relief
Steam systems

Approvals

Specifications
•

•
•
•
•
•

Inlet connections: 1/2” to 2” threaded connections(depending on valve bore size) (for flanged connections see
946 Flanged datasheet).

•

Temperature range: -196°C to +250°C(depending on body o’ring material)••

Pressure range: 0.3 to 28.0 bar (depending on valve bore size)

Materials of Construction

Designed in accordance with BS EN ISO-4126-1 & -7
PED 2014/68/EU (CE)PE(S)R UK SI 2016 No. 1105 (UKCA)
EAC
Leak tightness at 90% set pressure to API 527 andin accordance with EN ISO 4126-1
Materials meet the requirements of BAM (Germany)for oxygen service

Seal Materials

Component

Material

Grade

Inlet

Brass

CZ132 /
CW602N

This valve using metal to metal sealing. There is a choice ofo’ring used for the sealed cap/lever.

Outlet Body (10mmbore valve)

BronzeSB-62 C8360

Outlet Body (15, 20 &25mm bore valves)

Stainless Steel

SpringStainless Steel

1.4310 (302)

Disc

Stainless Steel1.4401 (316)1.4408 (316)

O'ring material

Temperature Range

Viton® (FKM)-20°C to +250°C

Nitrile (NBR)-196°C to +150°C

Silicone-50°C to +250°C

PTFE-196°C to +250°C

EPDM-40°C to +150°C-196°C is only suitable for sealed cap/sealed lever valves
Standard seal materials shown, others are available.

Easing Gear / Lifting Gear / Top Fitting Options•

Sealed Cap (gas tight cap)

SeetruLimited

That’s Safety!

•

Sealed lever (gas tight)•

Rota-lift (not gas tight)•

Open Lever (not gas tight)

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55
Page 10

Technical information by bore size
Bore size

10mm (93610)

Inlet Size

1/2"

3/4"

15mm (93615)
1"

1"

1 1/4"

20mm (93620)
1 1/2"

1"

1 1/4"

25mm (93625)
1 1/2"

1"

1 1/4" 1 1/2"

2"

Outlet Size

1"

1 1/2"

2"

2"

Flow Area

78.5mm²

177mm²314mm²491mm²H - Height (Sealed Lever version)

114mm

168mm

141mm

225mm

TÜV alloted outflow coefficient

0.85 (0.7 below 0.8 bar)0.85 (0.7 below 0.8 bar)0.85 (0.7 below 0.8 bar)0.85 (0.7 below 0.8 bar)

1.0

2.1

3.5

4.2

0.3 to 28.0

0.3 to 28.0

0.3 to 28.0

0.3 to 20.0

Weight (approximate) Kg
Set Pressure range - PED (CE) bar
Relieving pressure/fully open pressure

Set pressure +10% (0.1 bar below 1.0 bar)

Reseating pressure

Set pressure -10% (0.3 bar below 3.0 bar)•TÜV alloted outflow coefficients for pressures above 3.0/4.0 bar, for lower
pressures please see the flow rate tables or contact Seetru.
Maximum permissible built up back pressure = 10% of set pressure at or below
which flow is not reduced.
Stable operation on flows down to 50% of valve rated capacity.
Leak tightness at 90% set pressure to API 527 and in accordance with EN ISO
4126-1•••

Valve Drawing

Standard INLET Connection Types•

BSP parallel male thread•

BSP taper male thread•

NPT male thread•

BSP parallel female thread (limited option)

H

Standard OUTLET Connection Types•

BSP parallel female thread

Valve Selection Guide
Valve type

Select Bore

Inlet Size

Inlet Thread TypeTop Fitting

O'ring material(for cap)

Set pressure

936

Select bore size
from above table

Select inlet size
from above table

Select Inlet
Thread type

Select easinggear/top fitting

See table

Set pressure fromavailable range

EAC marking available upon request*Please send your selected details to Seetru and we can provide the full ordering code, price and lead-time.

Example of Valve Selection Process
ExampleSelection

936

15

1"

BSP parallel

Rota Lift

Viton

17.5 bar

Valve Type

Bore = 15mm

Inlet Size

Inlet Thread
Type

Top Fitting

O'ringSet Pressure

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56
Page 11

Capacity Table - In accordance with TÜV, AIR at 0°C and 1013mbar. Normal m³/hour
Type 936: Flow rates at 10% above the set pressure
Bore Size (D0)

Set Pressure
bar

psi

10mm

15mm

20mm

25mm

Nm³/HourNm³/HourNm³/HourNm³/Hour

0.3

4.35

48.5

109.2

194.2

303.5

0.5

7.25

59.0

132.9

236.2

369.1

1

14.5

96.1

216.2

384.4

600.6

2

29

146.1

328.7

584.4

913.2

3

43.5

196.1

441.3

784.5

1225.8

4

58

246.1

553.8

948.6

1538.4

5

72.5

296.1

666.4

1184.7

1851.1

6

87.00

346.2

778.9

1384.82163.7

7

101.5

396.2

891.4

1584.82476.3

8

116

446.2

1004.01784.92788.9

9

130.5

496.2

1116.5

1985.03101.6

10

145

546.7

1229.12185.13414.2

15

217.5

796.3

1791.83185.54977.36540.4202901046.42354.64185.925362.5

1296.52917.35186.328

406

1446.63254.95786.5For any intermediate pressures/flows please contact Seetru

Capacity Table - In accordance with TÜV, STEAM. Kg/hour
Type 936: Flow rates at 10% above the set pressure
Bore Size (D0)

Set Pressure

10mm

15mm

20mm

25mm

bar

psi

Kg/hour of SteamKg/hour of SteamKg/hour of SteamKg/hour of Steam

0.3

4.35

37.6

84.5

150.2

234.7

0.5

7.25

46.6

104.8

186.3

291.1

1

14.5

76.6

172.5

306.6

479.0

2

29

115.1

259.0

460.5

719.5

3

43.5

153.2

344.6

612.7

957.4

4

58

190.9

429.7

763.9

1193.7

5

72.5

228.6

514.3

914.4

1428.7

6

87.00

266.1

598.6

1064.2

1662.9

7

101.5

303.4

682.6

1213.5

1896.2

8

116

340.6

766.5

1362.62129.1

9

130.5

377.9

850.4

1511.82362.2

10

145

415.1

933.9

1660.42594.4

15

217.5

600.3

1350.72401.33752.0

20

290

785.4

1767.23141.74909.0

25

362.5

970.5

2183.73882.228406

1081.92434.44327.9For any intermediate pressures/flows please contact Seetru

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57
Page 12

Enclosed Discharge Safety Relief Valves
for compressed air or gases

steam

cryogenics & liquefied gases

Seetru Limitedhydrogen

Safety valves made from Stainless Steel <Enclosed discharge valve with threaded connections <Metal to metal sealing <Type 946 Threaded
Example Applications
•
•
•
•
•
•
•

Air / gas compressors
Pressure vessels
Medical gases/Technical gases
Refrigeration (including ammonia)
Thermal relief
Steam systems
HydrogenSpecifications

Approvals

•

•
•
•
•
•

Inlet connections: 1/2” to 2” threaded connections(depending on valve bore size) *For flanged connections see
datasheet 946 Flanged•

Temperature range: -50°C to +250°C(depending on body o’ring material)•

Pressure range: 0.3 to 28.0 bar (depending on valve bore size)

Designed in accordance with BS EN ISO-4126-1 & -7
PED 2014/68/EU (CE)PE(S)R UK SI 2016 No. 1105 (UKCA)
EAC
Leak tightness at 90% set pressure to API 527 andin accordance with EN ISO 4126-1

Seal Materials

Materials of Construction
Component

Material

GradeThis valve using metal to metal sealing. There is a choice ofo’ring used for the sealed cap/lever.

Inlet

Stainless Steel1.4401 (316)

Body

Stainless Steel1.4408 (316)Internal Parts

Stainless Steel1.4401 (316)

SpringStainless SteelDisc

Stainless SteelO’ring material – Top cap

Temperature Range

Viton® (FKM)-20°C to +250°C

Nitrile (NBR)-30°C to +150°C

1.4310 (302)

Silicone-50°C to +250°C

AISI 440B

EPDM-40°C to +150°C

Standard seal materials shown, others are available.

Easing Gear / Lifting Gear / Top Fitting Options•

Sealed Cap (gas tight cap)

SeetruLimited

That’s Safety!

•

Sealed lever (gas tight)•

Rota-lift (not gas tight)

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Page 58
13

Technical information by bore size
Bore size

10mm (94610)

Inlet Size

1/2"

3/4"

15mm (94615)
1"1"

1 1/4"

20mm (94620)
1 1/2"

1"

1 1/4"

25mm (94625)
1 1/2"

1"

1 1/4" 1 1/2"

2"

Outlet Size

1"

1 1/2"

2"

2"

Flow Area

78.5mm²

177mm²314mm²491mm²H - Height (Sealed Lever version)

114mm

168mm

141mm

225mm

TÜV alloted outflow coefficient

0.85 (0.7 below 0.8 bar)0.85 (0.7 below 0.8 bar)0.85 (0.7 below 0.8 bar)0.85 (0.7 below 0.8 bar)

1.0

2.1

3.5

4.2

0.3 to 28.0

0.3 to 28.0

0.3 to 28.0

0.3 to 20.0

Weight (approximate) Kg
Set Pressure range - PED (CE) bar
Relieving pressure/fully open pressure

Set pressure +10%(0.1 bar below 1.0 bar)

Reseating pressure

Set pressure -10%
(0.3 bar below 3.0 bar)•TÜV alloted outflow coefficients for pressures above 3.0/4.0 bar, for lower
pressures please see the flow rate tables or contact Seetru.
Maximum permissible built up back pressure = 10% of set pressure at or below
which flow is not reduced.
Stable operation on flows down to 50% of valve rated capacity. Leak tightness
at 90% set pressure to API 527 and in accordance with EN ISO 4126-1••

Valve Drawing

Standard INLET Connection Types•

BSP parallel male thread•

BSP taper male thread•

NPT male thread•

BSP parallel female thread (limited option)

H

Standard OUTLET Connection Types•

BSP parallel female thread

Valve Selection Guide
Valve type

Select Bore

Inlet Size

Inlet Thread TypeTop Fitting

O'ring material(for cap)

Set pressure

946

Select bore size
from above table

Select inlet size
from above table

Select Inlet
Thread type

Select easinggear/top fitting

See table

Set pressure fromavailable range

EAC marking available upon request*Please send your selected details to Seetru and we can provide the full ordering code, price and lead-time.

Example of Valve Selection Process
ExampleSelection

946

15

1"

BSP parallel

Sealed Lever

Viton

17.5 bar

Valve Type

Bore = 15mm

Inlet Size

Inlet Thread
Type

Top Fitting

O'ringSet Pressure

SeetruLimited

That’s Safety!

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Page 5914

Capacity Table - In accordance with TÜV, AIR at 0°C and 1013mbar. Normal m³/hour
Type 946: Flow rates at 10% above the set pressure
Bore Size (D0)

Set Pressure
bar

psi

10mm

15mm

20mm

25mm

Nm³/HourNm³/HourNm³/HourNm³/Hour

0.3

4.35

48.5

109.2

194.2

303.5

0.5

7.25

59.0

132.9

236.2

369.1

1

14.5

96.1

216.2

384.4

600.6

2

29

146.1

328.7

584.4

913.2

3

43.5

196.1

441.3

784.5

1225.8

4

58

246.1

553.8

948.6

1538.4

5

72.5

296.1

666.4

1184.7

1851.1

6

87.00

346.2

778.9

1384.82163.7

7

101.5

396.2

891.4

1584.82476.3

8

116

446.2

1004.01784.92788.9

9

130.5

496.2

1116.5

1985.03101.6

10

145

546.7

1229.12185.13414.2

15

217.5

796.3

1791.83185.54977.36540.4202901046.42354.64185.925362.5

1296.52917.35186.328

406

1446.63254.95786.5For any intermediate pressures/flows please contact Seetru

Capacity Table - In accordance with TÜV, STEAM. Kg/hour
Type 946: Flow rates at 10% above the set pressure
Bore Size (D0)

Set Pressure

10mm

15mm

20mm

25mm

bar

psi

Kg/hour of SteamKg/hour of SteamKg/hour of SteamKg/hour of Steam

0.3

4.35

37.6

84.5

150.2

234.7

0.5

7.25

46.6

104.8

186.3

291.1

1

14.5

76.6

172.5

306.6

479.0

2

29

115.1

259.0

460.5

719.5

3

43.5

153.2

344.6

612.7

957.4

4

58

190.9

429.7

763.9

1193.7

5

72.5

228.6

514.3

914.4

1428.7

6

87.00

266.1

598.6

1064.2

1662.9

7

101.5

303.4

682.6

1213.5

1896.2

8

116

340.6

766.5

1362.62129.1

9

130.5

377.9

850.4

1511.82362.2

10

145

415.1

933.9

1660.42594.4

15

217.5

600.3

1350.72401.33752.0

20

290

785.4

1767.23141.74909.0

25

362.5

970.5

2183.73882.228406

1081.92434.44327.9For any intermediate pressures/flows please contact Seetru

SeetruLimited

That’s Safety!

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60
Page 15

Enclosed Discharge Safety Relief Valves
for compressed air & gas

Seetru Limitedhydrogen
Safety valves made with a Brass or Stainless Steel body and Stainless Steel inlets <Enclosed discharge valve with threaded connections <Elastomer rubber sealing <Type 33020 / 34020 / 34320
Example Applications
•
•
•
•
•

Air / gas compressors
Pressure vessels
Pneumatic systems
Medical gases/Technical gases
Hydrogen (with 316 stainless steel inlet)

Specifications

Approvals

•
•

•
•
•
•

Inlet connections: 3/8” to 1/2” threaded inlet connections
Temperature range: -40°C to +200°C(depending on body rubber seal material)•

Pressure range: 55.0 to 103.4 bar

Designed in accordance with BS EN ISO-4126-1 & -7
PED 2014/68/EU (CE)PE(S)R UK SI 2016 No. 1105 (UKCA)
EAC

Materials of Construction
Component

Valve Type

Material

Grade

Inlet

33020

Stainless Steel1.4305 (303)34020

Stainless Steel1.4305 (303)34320

Stainless Steel1.4401 (316)

33020

Brass

CZ132

34020

Stainless Steel1.4408 (316)

O’ring material – Top cap

Temperature Range

34320

Stainless Steel1.4408 (316)

Viton® (FKM)-15°C to +200°C

All

Stainless Steel

302

Nitrile (NBR)-40°C to +120°C

Body

SpringSeal Materials
This valve using metal to metal sealing. There is a choice ofo’ring used for the sealed cap/lever.

Drawing showing all component materials available upon request.

Standard seal materials shown, others are available.

Top fitting

THESE VALVES SHOULD ONLY BE TESTED FOR SET PRESSURE
ON LIQUID PRIOR TO FINAL INSTALLATION. VALVES THAT ARE
TESTED ON AIR & FULLY LIFTED WILL CAUSE DAMAGE TO THE
SEALING FACE.

Sealed Cap (gas tight cap)

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Page 6116

Technical information by bore size
Bore size

7.14mm (33020)

Inlet Size

3/8"

7.14mm (34020)

1/2"

3/8"

7.14mm (34320)

1/2"

3/8"

1/2"

Outlet Size

1/2"

1/2"

1/2"

Flow Area

40.04mm²

40.04mm²

40.04mm²

H - Height

96mm

96mm

96mm

TÜV alloted outflow coefficient

0.67

0.67

0.67

Weight (approximate) Kg

0.8

0.8

0.8

55.0 to 103.4 bar

55.0 to 103.4 bar

55.0 to 103.4 bar

Set Pressure range - PED (CE) bar
Relieving pressure/fully open pressure

Set pressure +10%

Reseating pressure

Set pressure -15%

Maximum permissible built up back pressure = 10% of set pressure at or below which flow is not reduced.

Valve Drawing

Standard INLET Connection Types
BSP parallel male thread•

BSP taper male thread•

NPT male thread

96mm

•

Standard OUTLET Connection Types•

BSP parallel female thread•

NPT female thread

H

Valve Selection Guide
Valve type

Inlet Size

Inlet Thread Type

Outlet Thread
Type

Seal Material

Set pressure

33020, 34020 or
34320(see materials)

Select inlet size
from above table

Select Inlet
Thread type

Select Oulet
Thread type

See table

Set pressure fromavailable range

EAC marking available upon request*Please send your selected details to Seetru and we can provide the full ordering code, price and lead-time.

Example of Valve Selection Process
ExampleSelection

33020

1/2"

NPT

NPT

Viton

100 barValve Type

Inlet Size

Inlet Thread
Type

Outlet Thread
Type

Seal Material

Set Pressure

SeetruLimited

That’s Safety!

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Page 6217

Capacity Table - In accordance with TÜV, AIR at 0°C and 1013mbar. Normal m³/hour
Type 33020, 34020 & 34320: Flow rates at 10% above the set pressure
Bore Size (D0)

Set Pressurebar

7.14mmpsi

Nm³/Hour

55

797.5

1124.060

8701224.565942.51325.07010151425.5751087.51526.0801160

1626.585

1,232.50

1727.09013051827.5951377.5

1928.0100

1450

2028.5103.4

1499.32096.9For any intermediate pressures/flows please contact Seetru

SeetruLimited

That’s Safety!

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Page 6318

Enclosed Discharge Safety Relief Valves
for compressed air & gas

Seetru Limitedhydrogen
Safety valves made with a Brass or Stainless Steel body and Stainless Steel inlets <Enclosed discharge valve with threaded connections <Elastomer rubber sealing <Type 33110 / 34110 / 34410
Example Applications
•
•
•
•
•

Air / gas compressors
Pressure vessels
Pneumatic systems
Medical gases/Technical gases
Hydrogen (with 316 stainless steel inlet)

Specifications

Approvals

•
•

•
•
•
•

Inlet connections: 3/8” to 1/2” threaded inlet connections
Temperature range: -40°C to +200°C(depending on body rubber seal material)•

Pressure range: 27 to 36 & 48.3 to 241.3 bar

Designed in accordance with BS EN ISO-4126-1 & -7
PED 2014/68/EU (CE)PE(S)R UK SI 2016 No. 1105 (UKCA)
EAC

Materials of Construction
Component

Valve Type

Material

Grade

Inlet

33110

Stainless Steel

303

34110

Stainless Steel

303

34410

Stainless Steel

316

33110

Brass

CZ122

34110

Stainless Steel316

O’ring material – Top cap

Temperature Range

34410

Stainless Steel

316

Viton® (FKM)-15°C to +200°C

All

Stainless Steel

302

Nitrile (NBR)-40°C to +120°C

Body

SpringSeal Materials
This valve using metal to metal sealing. There is a choice ofo’ring used for the sealed cap/lever.

Drawing showing all component materials available upon request.

Standard seal materials shown, others are available.

Top fitting

THESE VALVES SHOULD ONLY BE TESTED FOR SET PRESSURE
ON LIQUID PRIOR TO FINAL INSTALLATION. VALVES THAT ARE
TESTED ON AIR & FULLY LIFTED WILL CAUSE DAMAGE TO THE
RETURN TO CONTENTS PAGE
SEALING FACE.

Sealed Cap (gas tight cap)

SeetruLimited

That’s Safety!

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Page 64
19

Technical information by bore size
Bore size

3.66mm (33110)

3.66mm (34110)

3.66mm (34410)

Inlet Size

3/8"

1/2"

3/8"

1/2"

3/8"

1/2"

Outlet Size

3/8"

1/2"

3/8"

1/2"

3/8"

1/2"

Flow Area

10.52mm²

10.52mm²

10.52mm²

H - Height

92mm

92mm

92mm

TÜV alloted outflow coefficient

0.73

0.73

0.73

Weight (approximate) Kg

0.8

0.8

0.8

27 to 36 & 48.3 to 241.3 bar

27 to 36 & 48.3 to 241.3 bar

27 to 36 & 48.3 to 241.3 bar

Set Pressure range - PED (CE) bar
Relieving pressure/fully open pressure

Set pressure +10%

Reseating pressure

Set pressure -10%

Maximum permissible built up back pressure = 10% of set pressure at or below which flow is not reduced.

Valve Drawing

Standard INLET Connection Types•

BSP parallel male thread•

BSP taper male thread•

NPT male threadStandard OUTLET Connection Types•

BSP parallel female thread•

NPT female thread

H

Valve Selection Guide
Valve type

Inlet Size

Inlet Thread Type

Outlet Thread
Type

Seal Material

Set pressure33110, 34110 or
34410(see materials)

Select inlet size
from above table

Select Inlet
Thread type

Select Oulet
Thread type

See table

Set pressure fromavailable range

EAC marking available upon request*Please send your selected details to Seetru and we can provide the full ordering code, price and lead-time.

Example of Valve Selection Process
ExampleSelection

33110

1/2"

BSP parallel

BSP parallel

Viton

100 barValve Type

Inlet Size

Inlet Thread
Type

Outlet Thread
Type

Seal Material

Set Pressure

SeetruLimited

That’s Safety!

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65
Page 20

Capacity Table - In accordance with TÜV, AIR at 0°C and 1013mbar. Normal m³/hour
Type 33110, 34110 and 34410: Flow rates at 10% above the set pressure
Bore Size (D0)

Set Pressurebar

3.66mmpsi

Nm³/Hour

27

391.5

160.7

30

435

177.9

33

478.5

195.2

36

522

212.5

48

696

281.5

50

725

293.0

60

870.00

350.6

70

1015

408.1

80

1160

456.7

90

1305

523.2

100

1450

580.8

150

2175

868.5

200

2900

1156.22413494.51392.1

For any intermediate pressures/flows please contact Seetru

SeetruLimited

That’s Safety!

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66
Page 21

Enclosed Discharge Safety Relief Valves
for compressed air or gases

cryogenic & liquefied gas

refrigeration

Seetru Limitedhydrogen

Safety valves with either Bronze or Stainless Steel body <Enclosed discharge valve with threaded connections <Type 329
Example Applications
•
•
•
•
•
•
•
•
•
•

Air/Gas systems
Natural Gas
CNG/LNG
Pressure vessels
Medical gases
Technical Gases
CO2 refrigeration
Ammonia refrigeration (Stainless steel)
Cryogenic applications
Liquefied gases

Specifications

Approvals•

Inlet connections: 3/8” to 3/4”•

Temperature range: -196°C to +70°C•

Pressure range: 53.0 to 370.0 bar

•
•
•
•
•
•

Designed in accordance with BS EN ISO-4126-1 & -7
PED 2014/68/EU (CE)PE(S)R UK SI 2016 No. 1105 (UKCA)
ASME BPVC VIII.1 & XIII (UV)
EAC
CRN

Materials of Construction
Component

Material

Grade

Inlet

Stainless Steel1.4401 (316)BodyBronzeC83600

Stainless Steel1.4408 (316)Brass

BS EN 12164
CW614N

Stainless Steel1.4401 (316)

Stainless Steel

1.4310 (302)Internal Parts

SpringSeetruLimited

That’s Safety!

Seal Materials
Seal Material

Temperature Range

PTFE (up to 202 bar)
PPS (202 to 370 bar)

-196°C to +70°C

Standard seal materials shown, others are available.

Top Fitting Options- Standard Option
Sealed Cap (gas tight cap)

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67
Page 22

Valve drawing

Technical information by bore size
Bore size

6mm

Inlet Size

3/8"

1/2"

3/4"

3/4"

Flow Area

28.2mm²

H - Height

100mm (53.0 to 240.0 bar)
114mm (240.0 to 370.0 bar)TÜV alloted outflow coefficient

0.77

NB Certified rated slope (ASME)

0.7scfm/psia

Weight (approximate) Kg

H
OUTLET
CONNECTION

Outlet Size

0.8

Set Pressure range - PED (CE) bar

53.0 to 370.0

Set Pressure range - ASME (UV) psi

768.5 to 5365.0

Relieving pressure/fully open pressure

Set pressure +10%

Reseating pressure

Set pressure -15%

Maximum permissible built up back pressure = 10% of set pressure at or below whichflow is not reduced.

Standard Thread Connection Types•

BSP Parallel male thread•

BSP Taper male thread•

NPT male threadStandard Outlet Connection Types•

BSP Parallel female thread•

NPT female thread

Valve Selection Guide
Valve Type

Stainless Steel329

Approval
Required

Body Material

BronzeSelect Bore

Inlet Size

Inlet Thread
Type

Outlet Thread
Type

Easing Gear

Seal Material

6mm

Select inlet size
from above
table

Select Inlet
thread type

Select Outlet
thread type

Sealed cap

PTFE

PED (CE)PED (CE), ASME
(UV, NB), CRN

EAC marking available upon request
Please send your selected details to Seetru and we can provide the full ordering code, price and lead-time

Example of Valve Selection Process
ExampleSelection

Bronze329

PED (CE)

6

1/2"

NPT

NPT

Sealed Cap

PTFE

175 bar

Body
Material

Valve TypeApproval

Bore = 6mm

Inlet Size

Inlet Thread
Type

OutletThread TypeTop Fitting

Seal

Set Pressure

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68
Page 23

Capacity Table - In accordance with TÜV, AIR at 0°C and 1013mbar. Normal m³/hour
Type 329: Flow rates at 10% above the set pressure
Bore Size (D0)

Set Pressure

6mm

bar

psi

Nm³/Hour

53

768.5

879.6

60

870.0

993.8

70

1015.01156.9801160.01320.0901305.01483.11001450.01646.3150

2175.02461.9200

2900.03277.52503625.04093.1300

4350.04908.7350

5075.05724.4370

5365.06050.6

For any intermediate pressures/flows please contact Seetru

Capacity Table - In accordance with ASME BPVC.XIII, AIR at 60°F and 14.7 psia/scfm. SCFM
Type 329: Flow rates at 10% above the set pressure
Bore Size (D0)

Set Pressure

6mm

psi

bar

SCFM

768.5

53

602

870

60

680

913.5

63

714

1203.5

83

937

1305

90

1015

1450

100

1127

2175

150

1685

2900

200

2243

2929

202

2266

3480

240

2690

3625

250

2802

4350

300

3360

5075

350

3918

5365

370

4141

For any intermediate pressures/flows please contact Seetru

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Page 69
24

Enclosed Discharge Safety Relief Valves
for compressed air & gas

Seetru LimitedhydrogenType B4605 / B6605 / 359

Safety valves made from Stainless Steel <Enclosed discharge valve with threaded connections <Example Applications
•
•
•
•
•
•

Air/Gas compressors
Natural Gas
Pressure vessels
Medical gases
Technical Gases
Hydrogen production/generation

Specifications

Approvals

•
•

•
•
•
•
•
•

•

Inlet connections: 3/8” and 1/2”
Temperature range:◦ 0°C to 200°C (with 1.4057 (431) stainless steel inlet)◦ -50°C to 150°C (with 1.4401 (316) stainless steel inlet)
Pressure range: 35.0 to 500.0 bar

Materials of Construction

Designed in accordance with BS EN ISO-4126-1 & -7
PED 2014/68/EU (CE)PE(S)R UK SI 2016 No. 1105 (UKCA)
ASME BPVC VIII.1 & XIII (UV)
EAC
CRN

Inlet Seat Material

Component

Material

GradeThis valve seals using a metal ball design

Inlet

Stainless Steel

1.4057 (431)

Seal Material

Temperature Range

1.4401 (316)

Stainless steel 1.4057 (431)0°C to +200°C-50C to +150°C

Body

Stainless Steel1.4408 (316)

Stainless steel 1.4401 (316)Internal Parts

Stainless Steel1.4305 (303)Standard seal materials shown, others are available.

SpringStainless Steel

1.4310 (302)Top Fitting Options- Standard Option
Sealed Cap (gas tight cap)

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70
Page 25

Valve drawing

Technical information by bore size
Bore size

4.6mm

Inlet Size

3/8"

1/2”

Outlet Size

1/2"

Flow Area

16.6mm²

H - Height96mm

TÜV alloted outflow coefficient

0.402

NB Certified rated slope (ASME)

0.34 scfm/psia

Weight (approximate) Kg

H0.8

Set Pressure range - PED (CE) bar

35.0 to 500.0

Set Pressure range - ASME (UV) psi

507.5 to 7250.0

Relieving pressure/fully open pressure

Set pressure +10%

Reseating pressure

Set pressure -10%

IMPORTANT NOTE:

Maximum permissible built up back pressure = 10% of set pressure at or below whichflow is not reduced

These valves should only be tested for set pressure on liquidprior to final installation. Valves that are tested on air & fully
lifted will cause damage to the sealing face.

Standard Thread Connection Types

Standard Outlet Connection Types•

BSP Parallel male thread•

BSP Parallel female thread•

BSP Taper male thread•

NPT female thread•

NPT male thread

Valve Selection Guide
Approval Required

Valve Type

Inlet Material

B6605

Stainless Steel 1.4057 (431)PED (CE)

B4405

Stainless Steel 1.4401 (316)PED (CE)(Avaialble for both Inlet materials)

B6105

Stainless Steel 1.4057 (431)PED (CE), ASME (UV, NB), CRN

B4105

Stainless Steel 1.4401 (316)PED (CE), ASME (UV, NB), CRN

SelectBore

Inlet Size

Inlet Thread
Type

Outlet Thread
Type

EasingGear

Seal
Material

4.66mmSelect inlet
size fromabove table

Select Inlet
thread type

Select Outlet
thread type

Sealed cap

Metal ballseal

EAC marking available upon request*Please send your selected details to Seetru and we can provide the full ordering code, price and lead-time.

Example of Valve Selection Process
ExampleSelection

1.4057 (431)359

PED (CE)

4.66

1/2"

BSP taper

BSP

Sealed Cap

Ball Seal

385 bar

Inlet
Material

Valve TypeApproval

Bore =
4.6mm

Inlet Size

Inlet Thread
Type

OutletThread TypeTop Fitting

Seal

Set Pressure

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Page 7126

Capacity Table - In accordance with TÜV, AIR at 0°C and 1013mbar. Normal m³/hour
Flow rates at 10% above the set pressure
Bore Size (D0)

Set Pressure

4.6mm

bar

psi

Nm³/Hour

35

507.5

179.8

50

725.0

254.9

100

1450.0505.2

1502175.0755.5

2002900.01005.82503625.01256.0300

4350.01506.3350

5075.01756.6400

5800.02006.94506525.02257.2500

7250.02507.5For any intermediate pressures/flows please contact Seetru

Capacity Table - In accordance ASME section VIII Div I, AIR at 60°F and 14.7 psia/scfm. SCFM
Flow rates at 10% above the set pressure
Bore Size (D0)

Set Pressure

4.6mm

psi

bar

SCFM

507.5

35

195

725

50

276

1450

100

547

2175

150

818

2900

200

1090

3625

250

1361

4350

300

1632

5075

350

1903

5800

400

2174

6525

450

2445

7250

500

2716

For any intermediate pressures/flows please contact Seetru

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72
Page 27

Enclosed Discharge Safety Relief Valves
for compressed air or gases

cryogenic & liquefied gas

Seetru LimitedhydrogenType
94605 / 946H5 / 95605 / 956H5

Safety valves made from stainles steel <Enclosed discharge with threaded connections <Example Applications
•
•
•
•
•
•

Air/Gas Compression
Air/Gas Boosters
Natural Gas
Pressure Vessels
Hydrogen Production
Hydrogen Storage

Specifications
•

•

•

•

Inlet Connections◦ ½” NPT, BSP & BSPT
◦ 9/16” Cone & Thread◦ 3/4” Cone & Thread
Outlet Connections◦ ½” NPT & BSP◦ ¾” NPT & BSP◦ 1” NPT & BSP
Temperature Range◦ 0° to 300°C as standard◦ -196°C to 300°C H2 option
Pressure Range◦ 35.0 to 515 bar (9*605)◦ 35.0 to 1100 bar (9*6H5)*Maximum set pressure for steam is 85 bar

Key Features
•
•
•

•
•
•
•
•

Approvals

Materials of Construction••

Component

Valve Type
2nd Digit

Material

Grade

Seat

4

Stainless

1.40575
4&5

Stainless1.4401Disc

4Stainless

1.40575
4&5

Gaskets

4&5•

S20910Body

SpringCompact and space saving design
Designed and built for repeatable operation
Advanced sealing technology with super-lapped
hard-faced seat and disc, designed to offer robust
high-performance sealing
Orientable gas-tight packed lever option (9*6H5 only)
Simple and robust design with three moving parts
Maintenance friendly design
All wrought construction with no castings
Designed with Hydrogen embrittlement resistant materials(H2 option)•

EAC marking available upon request

Ceramic

Stainless

BS EN ISO 4126-1
PED 2014/68/EU◦ Module B – TÜV Rheinland◦ Module D – LRQA Deutschland
PE(S)R 2016 (UKCA)◦ Module B – TÜV UK◦ Module D – LRQA UK
Seat tightness better than API 527

Top Fitting Options

1.4401•PTFE

Sealed Cap (gas tight cap)•

Sealed lever (gas tight)

For Hydrogen applications above 515 bar, a ceramic disc is required, use type 956H5

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Page
Page281

Technical information by bore size
Model No.

9*605

9*6H5

Bore

4.6mm

Inlet

1/2"

Outlet9/16"
1/2"

Flow Area

1/2"

9/16"

3/4”

1/2"

3/4"

1"

16.6 mm²

Height H

158

FEMALE CONE & THREAD INLET

202

Kdr

0.75

Weight

9*6H5

1.5 kg

2.8 kg

9*605Standard INLET Connection Types•

BSP (male) max 515 bar•

BSPT (male) max 515 bar•

NPT (male) max 1034 bar•

Cone & Thread (female) max 1100 bar

HHStandard OUTLET Connection Types•

BSP (female)•

NPT (female)
INLET THREAD

INLET THREAD

Please send your selected details to Seetru and we can provide the full ordering code, price and lead-time.

Valve Selection Guide - Type 94605, 946H5, 95605 & 956H5
Valve typeH2 or low temperature
valve type 2nd digit
Yes

9*6H5

Inlet Connection

9/16” & 3/4”

C&T

Outlet Size

Outlet Connection

Easing Lever(Sealed Lever)

NPT, BSP

9*6H5 only

No

9*605
5

Inlet Size

1/2”

4

1/2”

NPT, BSP, BSPT

1/2”
9/16” & 3/4”

1/2”, 3/4”, 1”

C&T

Example of Valve Selection Process for Order Code 956H5F1297
ExampleSelection

Approval

Materials from above Table

Bore

Inlet Size

Inlet Thread

Outlet Size

OutletThreadDuty

Set Pressure

PED and UKCA
(ASME in process)

5 = Body=1.4401,
Seat=S20910, Disc=Ceramic

4.6mm

1/2"

NPT

3/4”

NPT

Hydrogen1000 bar

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Page292PageCapacity Table -Per EN 4126-7 and at 10% Overpressure
Type 94605 / 946H5 / 95605 / 956H5: Flow rates at 10% above the set pressure.
Set Pressure

Flow of Air

Set Pressure

Flow of Hydrogen

bar

psi

Nm3/hrbar

psi

Nm3/hr

35

507.5

335.5

35

507.5

1273.2

50

725

475.5

50

725

1804.9751087.5709.0

751087.52691.1

100

1450

942.5

100

1450

3577.21502175

1409.4150

2175

5349.5200

2900

1876.4200

2900

7121.82503625

2343.3250

3625

8894.1300

4350

2810.3300

4350

10666.3350

5075

3277.2350

5075

12438.6

400

5800

3744.2400

5800

14210.94506525

4211.14506525

15983.3500

7250

4678.1500

7250

17755.5550

7975

5145.1550

7975

19527.8

600

8700

5612.0600

8700

21300.1

650

9425

6078.96509425

23072.4

700

10150

6545.9700

10150

24844.7

750

10875

7012.8750

10875

26617.1

800

11600

7479.8800

11600

28389.2

850

12325

7946.7850

12325

30161.5

900

13050

8413.7900

13050

31933.8

950

13775

8880.6950

13775

33706.1

1000

14500

9347.6

1000

14500

35478.5

1050

15225

9814.5

1050

15225

37250.7

1100

15950

10281.5

1100

15950

39023.0

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Page303
PageEnclosed Discharge Safety Relief Valves
for compressed air or gases

steam

refrigeration

Seetru Limitedhydrogen

Safety valves made from Stainless Steel <Enclosed discharge valve with flanged connections <Metal to metal sealing <Type 946 Flanged
Example Applications
•
•
•
•
•
•
•

Air / gas compressors
Pressure vessels
Medical gases/Technical gases
Refrigeration (including ammonia)
Thermal relief
Steam systems
HydrogenSpecifications

Approvals

•

•
•
•
•
•

Inlet connections: DN15 (1/2), DN20 (3/4”) or DN25 (1”)
flange – DIN EN1092 and ANSI flanges are available•

Temperature range: -50°C to +250°C(depending on body o’ring material)•

Pressure range: 0.3 to 28.0 bar

Designed in accordance with BS EN ISO-4126-1 & -7
PED 2014/68/EU (CE)PE(S)R UK SI 2016 No. 1105 (UKCA)
EAC
Leak tightness at 90% set pressure to API 527 and inaccordance with EN ISO 4126-1

Seal Materials

Materials of Construction
Component

Material

GradeThis valve using metal to metal sealing. There is a choice ofo’ring used for the sealed cap/lever.

Inlet & Outlet Flanges

Stainless Steel1.4401 (316)

Body

Stainless Steel1.4408 (316)Internal Parts

Stainless Steel1.4401 (316)

SpringStainless SteelDisc

Stainless SteelO’ring material – Top cap

Temperature Range

Viton® (FKM)-20°C to +250°C

Nitrile (NBR)-30°C to +150°C

1.4310 (302)

Silicone-50°C to +250°C

AISI 440B

EPDM-40°C to +150°C

Standard seal materials shown, others are available.

Easing Gear / Lifting Gear / Top Fitting Options•

Sealed Cap (gas tight cap)

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•

Sealed lever (gas tight)

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79
Page 31

Valve Drawing

Technical information by bore size
Bore size

10mm (94610)
DN15(1/2”)

Inlet Size

DN20
(3/4”)

DN25(1”)

DN25 (1")

Outlet Size

DN25 (1")

DN40 (1 1/2")

Flow Area

78.5mm²

177mm²H - Height (Sealed Lever version)

200mm

253mm

TÜV alloted outflow coefficient

0.85 (0.7 below 0.8 bar)0.85 (0.7 below 0.8 bar)

3.0

5.3

0.3 to 28.0

0.3 to 28.0

Set Pressure range - PED (CE) bar
Relieving pressure/fully open pressure

Set pressure +10%(0.1 bar below 1.0 bar)

Reseating pressure

Set pressure -10%
(0.3 bar below 3.0 bar)•

OUTLET FLANGE
CONNECTION

H

95 REF

Weight (approximate) Kg

10mm bore – 94610

15mm (94615)

INLET FLANGE
CONNECTION

95 REF15mm bore – 94615

TÜV alloted outflow coefficients for pressures above 3.0 bar, for lower
pressures please see the flow rate tables or contact Seetru.
Maximum permissible built up back pressure = 10% of set pressure at or below
which flow is not reduced.
Stable operation on flows down to 50% of valve rated capacity.
Leak tightness at 90% set pressure to API 527 and in accordance with EN ISO
4126-1.

•••OUTLET FLANGE
CONNECTIONH•DIN EN1092 Flange PN16, PN25 or PN40•

ASME Flange CL150, CL300 or CL600

105 REF

Standard INLET Connection Types

INLET FLANGE
CONNECTION

105 REF

Standard OUTLET Connection Types•DIN EN1092 Flange PN16, PN25 or PN40•

ASME Flange CL150 or CL300

Valve Selection Guide
Valve type

Select Bore

Inlet Size

Inlet Flange Type

Outlet Flange
Type

Easing Gear

O'ring material(for cap)

946

Select bore size
from above table

Select inlet size
from above table

Select Inlet Flange
type

Select Outlet
Flange type

Select easinggear/top fitting

See table

EAC marking available upon request*Please send your selected details to Seetru and we can provide the full ordering code, price and lead-time.

Example of Valve Selection Process
ExampleSelection

946

10

DN20

DIN EN1092
Flange PN16

DIN EN1092
Flange PN16

Sealed Lever

Viton

10.5 bar

16.2 bar

Valve Type

Bore = 10mm

Inlet Size

Inlet Flange
Type

Outlet Flange
Type

Top Fitting

O'ringSet Pressure

Set Pressure

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80Page 32

Capacity Table - In accordance with TÜV, AIR at 0°C and 1013mbar. Normal m³/hour
Type 946: Flow rates at 10% above the set pressure
Bore Size (D0)

Set Pressure
bar

psi

10mm

15mm

Nm³/HourNm³/Hour

0.3

4.35

48.5

109.2

0.5

7.25

59.0

132.9

1

14.5

96.1

216.2

2

29

146.1

328.7

3

43.5

196.1

441.3

4

58

246.1

553.8

5

72.5

296.1

666.4

6

87.00

346.2

778.9

7

101.5

396.2

891.4

8

116

446.2

1004.0

9

130.5

496.2

1116.5

10

145

546.7

1229.1

15

217.5

796.3

1791.8202901046.42354.625362.5

1296.52917.328

406

1446.63254.9For any intermediate pressures/flows please contact Seetru

Capacity Table - In accordance with TÜV, STEAM. Kg/hour
Type 946: Flow rates at 10% above the set pressure
Bore Size (D0)

Set Pressure

10mm

15mm

bar

psi

Kg/hour of SteamKg/hour of Steam

0.3

4.35

37.6

84.5

0.5

7.25

46.6

104.8

1

14.5

76.6

172.5

2

29

115.1

259.0

3

43.5

153.2

344.6

4

58

190.9

429.7

5

72.5

228.6

514.3

6

87.00

266.1

598.6

7

101.5

303.4

682.6

8

116

340.6

766.5

9

130.5

377.9

850.4

10

145

415.1

933.9

15

217.5

600.3

1350.7

20

290

785.4

1767.2

25

362.5

970.5

2183.7284061081.92434.4For any intermediate pressures/flows please contact Seetru

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81
Page 33

Enclosed Discharge Safety Relief Valves
for compressed air & gas

Seetru LimitedhydrogenType 64613 / 64113 Flanged

Safety valves with Stainless Steel body <Enclosed discharge valve with flanged connections <Example Applications
•
•
•
•
•

Air / gas compressors
Pressure vessels
Pneumatic systems
Medical gases
Technical gases

Specifications

Approvals

•

•
•
•
•
•
•

•
•

Inlet connections: DN20 (3/4”) or DN25 (1”) DIN or ANSI
flanges
Temperature: -40°C to +200°C (depending on seal material)
Pressure range: 0.32 to 49.0 bar

Designed in accordance with BS EN ISO-4126-1 & -7
PED 2014/68/EU (CE)PE(S)R UK SI 2016 No. 1105 (UKCA)
ASME BPVC VIII.1 & XIII (UV)CRN
EAC

Materials of Construction
Component

Material

Grade

Inlet

Stainless Steel1.4401 (316)

Body

Stainless Steel1.4408 (316)Internal parts

Stainless Steel1.4401 (316)

SpringStainless Steel

1.4310 (302)

Seal Materials
Seal Material

Temperature Range

Viton® (FKM)-15°C to +200°C

Nitrile (NBR)-40°C to +120°C

Standard seal materials shown, others are available.

Easing Gear / Lifting Gear Options
Standard Option: Sealed Cap (gas tight cap)

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Other Option: Sealed lever (gas tight)

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82
Page 34

Valve Drawing

Technical information by bore size
Bore size

13.7mm

Inlet Size

DN20 (3/4”)

DN25 (1”)

Outlet Size

DN25 (1")

Flow Area

147.4mm²

H - Height (Sealed cap version)

197mm (up to 35 bar)
226mm (35-49 bar)TÜV alloted outflow coefficient

0.77

NB Certified rated slope (ASME)

3.47 scfm/psia

Weight (approximate) Kg

H

3.2

Set Pressure range - PED (CE) bar

0.32 to 49.0

Set Pressure range - ASME (UV) psi

20.3 to 710.5

Relieving pressure/fully open pressure

Set pressure +10% (0.3 bar below 1.4 bar)

Reseating pressure

Set pressure -10% (0.3 bar minimum)

Maximum permissible built up back pressure = 10% of set pressure at or below whichflow is not reduced. Stable operation on flows down to 50% of valve rated capacity.

INLET THREAD

Standard Thread Connection Types•DIN EN1092 Flange PN16, PN25 or PN40•

ASME Flange CL150, CL300 or CL600

Standard Outlet Connection Types•DIN EN1092 Flange PN16, PN25 or PN40•

ASME Flange CL150, CL300 or CL600

Valve Selection Guide
Approval
Required

Valve type

PED (CE)64613

PED (CE), ASME
(UV) & CRN

Inlet Size

Inlet Flange
Type

Outlet Flange
Type

Easing Gear

Select inlet size
from above table

Select Inlet
flange type

Select Outlet
flange type

Select easinggear/top fitting

Seal Material
Viton® (FKM)
Nitrile (NBR)

64113

Other

EAC marking available upon request*Please send your selected details to Seetru and we can provide the full ordering code, price and lead-time.

Example of Valve Selection Process
ExampleSelection

PED, ASME &
CRN

64113

DN20

DIN EN1092
Flange PN16

DIN EN1092
Flange PN16

Sealed Cap

Viton

3.5 barApproval

Valve Type

Inlet Size

Inlet Flange
Type

Outlet Flange
Type

Easing Gear

Seal

Set Pressure

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Page 8335

Capacity Table - In accordance with TÜV, AIR at 0°C
and 1013mbar. Normal m³/hour
Type 64613: Flow rates at 10% above the set pressure
Bore Size (D0)

Set Pressure

13.7mmCapacity Table - In accordance with ASME BPVC.XIII,
AIR at 60°F and 14.7 psia/scfm. SCFM
Type 64113: Flow rates at 10% above the set pressure
Bore Size (D0)

Set Pressure

13.7mmbarpsi

Nm³/Hour

psi

bar

SCFM

0.32

4.64

160.1

20.3

1.40

131.9

1

14.5

231.2

22.5

2.50

139.4

2

29

321.1

30

2.07

165.5

3

43.5

431.0

34.8

2.80

183.8

4

58

540.9

40

2.76

203.7

5

72.5

650.8

43.5

3.00

217.0

6

87

760.8

50

3.45

241.8

7

101.5

870.7

82

5.66

363.9

8

116

980.6

100

6.90

432.6

9

130.5

1090.5

150

10.34

623.4

10

145

1200.5

200

13.79

814.2

15

217.5

1750.1250

17.24

1005.0202902299.7300

20.69

1195.825362.5

2849.3350

24.14

1386.630435

3398.9400

27.59

1577.435507.53948.5435

30.00

1711.040580

4498.1450

31.03

1768.245652.5

5047.7500

34.48

1959.049

710.55487.4

507.5

35.00

1987.655037.93

2149.8600

41.38

2340.665044.83

2531.4700

48.28

2722.2

710.5

49.00

2762.3For any intermediate pressures/flows please contact Seetru

SeetruLimited

That’s Safety!

For any intermediate pressures/flows please contact Seetru

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84
Page 36Change-Over Valves
for compressed air or gases

Seetru Limited

cryogenic & liquefied gas

COV10 / COV13 / COV30

refrigerationhydrogen

Solutions for plant and process efficiency

Seetru Change-Over Valves

Change-over valves (sometimes referred to as selector valves or three-way valves) enables the switching of flow from
These where
valves areplantused ifshutdown
a plant shutdown
is impossible orfor process,engineeringor commercial reasons.
one safety valve to another. Typically used
is impossible
orundesirable
undesirable
for process,engineeringorWith change-over valves it is possible to switch over between parallel safety valves without interrupting operation, so thatcommercial reasons. With change-over valves it is possible to switch over between parallel safety valves withoutmaintenance work can be carried out on each safety valve in turn. Seetru products are widely recognised for their quality
interrupting operation, so that maintenanceworkEnquiry
can becarriedout on eachsafety valve| in+44turn.
Seetruchange-overand reliability.
Form| www.seetru.com| info@seetru.com(0) 117930 6100valves in combination with our safety valves provide the best solution for plant safety and efficiency. Seetru products arewidely recognised for their exceptional quality and reliability.
FeaturesFeatures

Patented Design -- Robust Construction

Lubricant Free Operation -- Compact and easy to use design

Can be fitted with a Bursting Disc -- Designed in accordance with BS EN 378
Pressure drops with 10.0mm for COV10 bore SRV- & 18.0mm for COV30 (in accordance with BS EN 13136)

Lockable handle(optional padlock available) Designed for ease of maintenance Option to degrease for Oxygen service Impossible to isolate both safety valves Adjustable Spindle Gland -- Ventable outlets for safe removal of Safety Valves

Seetru Change-Over Valves- Seat leakage EV 12266-1 Rate A

These valves are used if a plant shutdown is impossible or undesirable for process, engineering or commercial reasons.
Available
witha widerange of operation,
fittings andWith change-over valves it is possible to switch over between parallel- safetyvalveswithout
interrupting
so adaptors
thatmaintenance work can be carried out on each safety valve in turn. Seetru products are widely recognised for their quality- Optimised
using
Fluid Dynamics (CFD)
and reliability. Enquiry Form | www.seetru.com | info@seetru.com| +44 (0) 117
930Computational
6100

Fluid Mechanics

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Page 2

Fluid Mahcanics

The Seetru Change-Over Valves were designed and developed using Computational Fluid Dynamics (CFD) in order to simulate and optimise the flow of the fluids
through the valve.

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Page 5

Page
Page11537

Specifications: COV10
System Connections½” to 1” BSP, BSPT & NPT

Valve Connectiond½” NPT or 3/4” BSP (with or without orientators)

Change-Over Valve Kv

10.0 (Cv= 11.5)

Materials of Construction

Stainless SteelSeat Materials

25% Carbon filled P.T.F.E.

Temperature Range-196°C to +200°C

Max Design Pressure

75 barMaterial Certifiation

BS EN ISO10204 3.1 Pressure Retaining Parts (Optional Extra)

Safety Valve Orifice Size

Up to 10mm (Full Lift Type)Maximum Safety Valve Set Pressure

75 barSpecifications: COV13
System Connections

Please contact Seetru for information

Valve Connections

Please contact Seetru for information

Materials of Construction

Stainless Steel with Mild Steel or Stainless Steel Internals

Seat Materials

Elastomer
P.T.F.E

Maxium Safety valve Set Pressure

65.0 barTemperature Range-30 °C to 200 °C (subject to seal material)

Specifications: COV30
System Connections

1” to 1-1/2” BSP, BSPT, NPT, CL150 to CL600 & PN16 to PN100

Valve Connections¾” to 1” BSP, BSPT, NPT (with or without orientators), CL150 to CL600 & PN16 to PN100

Change-Over Valve Kv

30

Materials of Construction

CF8M/316/1.4401

Seat Materials

25% Carbon filled P.T.F.E.

Temperature Range-196°C to +200°C

Max Design Pressure

CL600 or PN100

Material Certifiation

BS EN ISO10204 3.1 Pressure Retaining Parts (Optional Extra)

Safety Valve Orifice Size

Up to 18mm (Full Lift Type)Maximum Safety Valve
Set Pressure

100 bar

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Page
Page11638

Operation Instructions: COV10 / COV30
1

Unlock handle if locking device fitted (recommended).

2

Starting in a motion away from the duty SRV, rotate handle through 180° (COV10) or 120° (COV10), either clockwiseor anticlockwise dependent uponstart starting position.

3

Once fully rotated, lock in position if locking device fitted (recommended).

4

If the now standby SRV is to be remove: with caution, un-tighten vent nut of standby Change-over arm by 1 to 2
revolutions to exhaust trapped fluid from change-over arm.

5

Once trapped fluid has de-pressurised, re-tighten vent plug with a tightening torque of 3.0 Nm.

6

Remove the standby SRV.

7

The user may plug the vacant outlet if desired, however sufficient safety procedures (for example Lock out Tag out)
must be in place to prevent inadv inadvertent change over, thus rendering the system un-protected against excessive pressure. If the outlet is plugged, vent arm of pressure, as previously described, prior to removal.

COV10

COV30

EN

OP

Seetru Change-Over Valves
These valves are used if a plant shutdown is impossible or undesirable for process, engineering or commercial reasons.
With change-over valves it is possible to switch over between parallel safety valves without interrupting operation, so thatmaintenance work can be carried out on each safety valve in turn. Seetru products are widely recognised for their quality
and reliability. Enquiry Form | www.seetru.com | info@seetru.com | +44 (0) 117 930 6100

Fittings, Adaptors and Connections

Fittings, Adaptors and Connections

The Seetru COV30 Flanged Change-Over Valve- The Seetru COV10 and COV30 Change-Over Valves can be supplied with a range of fittings and adaptors to provide compatibility with a large variety of systems.
- The COV30 is also available with flanged connections (A or PN).

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Page 6

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Page
Page117
39

Valves from Stock: Same-Day-Despatch
Our products are recognised globally for their exceptional quality andreliability, and in recent years Seetru have worked hard to maximise theefficiency of our manufacturing processes, to ensure that we are able tomeet demands for supply and distribution. We now hold a large variety ofsafety valves in stock, allowing customers to purchase certain quantities fromour website, and see them despatched on the same day.
Seetru offer atmospheric discharge safety valves and pipped discharge safetyvalves in brass / bronze or stainless steel. The Seetru LGS® range of pressure
relief valves (for liquid, steam, and gasses) are available in bronze construction,with open-lever and sealed-cap options. These valves can be fitted with PTFE
or EPDM seals, with both types having the WRAS approval - for installation on
public water supply systems.
Seetru also operate a standardised three-day-despatch delivery service, which
covers the entire range of valves we manufacture.

Safety Valve Testing Equipment: The Seetru Quicktester™
This compact, lightweight and portable design is very robust and able to meetthe demands of a busy maintenance workshop or mobile operation. The Seetru
Quicktester™ can be used with plant generated air supplies or with mobile bottled
gas. This test-bench can be supplied with a range of adaptors allowing connection
between 1/4” to 1” BSP as standard, additional adaptors are available increasing
the connection sizes up to 2” BSP. The Quicktester™ is also available with NPT
connection adaptors upon request. It is suitable for use with a wide range ofelastomer sealed valves

Liquid Level Gauges
There are many industrial applications that require the monitoringof the liquid level in tanks. While the function of a level gauge
is relatively simple, there are a variety of options available. The
suitability and robustness of construction materials play a role indetermining which gauge is required, as do the operating temperatureand pressure requirements. Seetru liquid level gauges are primarilyof two types, sight gauges and magnetic float by-pass gauges. Manyof the Seetru gauges are direct reading though most have optional
electronic remote reading systems and computer interfaces. The
range includes the Quickmount, Seemag and CPI gauges for industrial
and chemical applications and the Seeflex and Seemag for marine
applications.

Seetru Limited, Albion Dockside Works, Bristol, BS1 6UT, England.

Copyright© 2024 Seetru Limited