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Safety Valve AT 4541, 4542, 4543, 4545, 4580, 4581

Full lift safety valve. Flanged connections. Nodular iron, steel or stainless steel. Soft- or metal seated disc. DN20/40-200/300 (nodular iron DN25/40-200/300, stainless DN25/40-150/250), PN16-40

Dimension range20-200
PN16-40
Temperature range-270 to +450°C
MaterialNodular iron, steel, stainless steel

Variations

Article number Amount
AT 4541
AT 4542
AT 4543
AT 4545
AT 4580
AT 4581

Product information

Main facts

Dimension rangePNTemperature rangeMaterial
DN 25-10040-60ºC to 350 ºCNodular iron
DN 125-15016Nodular iron
DN20025Nodular iron
DN 20-15040-85ºC to 450 ºCSteel
DN 20025Steel
DN 20-15040-270ºC to 400 ºCStainless steel
DN20025Stainless steel

Range of Application

Safety valve for protection of pressure vessels and piping systems with liquids, air, gases and steam.

Quality Assurance

Approved by TÜV and several other classification authorities.
Fulfils the requirements according to ISO 4126.
Certificate SS-EN 10204, type 2, 3 and from most of the classification authorities.
Type of certificate has to be specified upon ordering.

CE-marking
Meets the requirements in AFS 2016:1 and 2014/68/EU (Pressure Equipment Directive) according to category IV, fluids group 1 and 2.


Material Specification

AT 4541/AT 4542 AT 4543/AT 4545 AT 4580/AT 4581
1 Body0.7043/nodular iron1.0619/SA 216 WCB1.4408/SA 351 CF8M
Gr.60-40-18SteelStainless steel
2 Seat1.4404/316L1.4404/316L1.4404/316L
3 Disc 1.4122/hardened1.4122/hardened1.4404/316L
stainless steelrostfritt stål
4 Spindle1.4404/316L1.4404/316L1.4404/316L
5 Spring1.1200, 1.8159, 1.1200, 1.8159,1.4310/stainless steel
1.7102/carbon steel1.7102/carbon steel
6aGuide1.4104, 1.0501, 1.4104, 1.0501, 1.4404/316L
0.7040/chrome- or carbon steel0.7040//chrome- or carbon steel
6bBush ring1.4104 tenifer/1.4104 tenifer/-
chrome steel teniferchrome steel tenifer
7 Bonnet 0.7040, 0.7043, 1.0619/0.7040, 0.7043, 1.0619/1.4408, 1.4404, 1.4571
nodular iron Gr.60-40-18,nodular iron Gr.60-40-18, /SA 351 CF8M, SA479
SA 216 WCBSA 216 WCB316L, SA 479 316Ti
8 Spring plate 2 pcs 1.0718/steel1.0718/steel1.4404/316L
9 Lock nut 1.4104 PTFE/1.4104 PTFE/1.4404 PTFE/
chrome steel PTFEchrome steel PTFE316L PTFE
10 Ball1.3541/hardened1.3541/hardened1.4401/316
stainless steelstainless steel
11aCap (2) 1.0718 or 0.7043/1.0718 or 0.7043/1.4404/316L
12L13 or Gr.60-40-1812L13 or Gr.60-40-18
11bLever (4) 1.0718 or 0.7043/1.0718 or 0.7043/1.4404/316L
12L13 or Gr.60-40-1812L13 or Gr.60-40-18

Dimension and Weight

AT 4541, 4542, 4543, 4545
DN Inlet20* 253240506580100125150200
DN Outlet40 40506580100125150200250300
Flow diameter18 2329374660749298125165
A 219 2343313724195296066636637981090
A with bellowsSee AT4547-series
B95 100110115120140160180200225300
C85 105115140150170195220250285290
D150 150200250300350400450450450700
Weight9 912162232567585131285
Dimensions in mm, weight in kg.
* Only AT 4543, 4545

Dimension and weight 4580, 4581

AT 4580, 4581
DN Inlet253240506580100125150
DN Outlet40506580100125150200250
Flow diameter 2329374660749298125
A (2)234331372419529606663663798
B100110115120140160180200225
C105115140150170195220250285
D150200250300350400450450450
Weight912162232567585131
Dimensions in mm, weight in kg
(2)= with gastight cap

Function and Design

Spring loaded and directly acting safety valve for air, gases and steam. With full lift opening characteristics.
For liquids, the safety valve has standard opening characteristics.
With lifting device for manual testing or with gas tight cap.
If possible, a soft sealing disc should be used since it has better tightness and is easier to renovate.

Technical Information

Overpressure
The safety valve is fully open at an overpressure exceeding the set pressure with a maximum of 5 %.
Max 10 % for liquids, when the valve has standard opening characteristics.
For set pressure lower than 1,0 bar, the overpressure is set pressure + 0,1 bar.
If lower overpressure is requested please contact Armatec.

Blowdown

Blowdown

Blowdown

Steam/air/gases:Max 10% at set pressure 3,0 bar and higher
Max 0,3 bar at set pressure 3,0 bar and lower
Liquids:Max 20% at set pressure 3,0 bar and higher
Max 0,6 bar at set pressure 3,0 bar and lower
If lower blowdown pressures are required please contact Armatec

Pressure and temperature

AT 4541/ AT 4543/ AT 4580/
AT 4542 AT 4545 AT 4581
SetTemp. SetTemp.Set Temp.
pressure max.-60°C topressure max.-85° topressure max.-270°C to
DNbar +350°Cbar+450°Cbar +400°C
20 - 40 -
25 40 40 40
32 40 40 40
40 40 40 40
50 40 40 37
65 40 40 28
80 4040 25
100 40 40 26
125 1628 24
150 16 2510
200 2525 -

Pressure and temperatures according to applied standards for each valve material.
At temperatures above 200oC the temperature has to be specified in the order, so that a high temperature spring is used.
If other temperatures and pressures limits are requested please contact Armatec.

Soft sealing

Temperature range soft sealed safety valves:
O-ringNeoprene (CR) K -40°C to +100°C e.g. refrigants
Ethylene (EPDM) D -45°C to +150°C e.g. hot water and low temperature steam
Viton (FPM) L -20°C to +180°C, e.g. oil and air

Additional information

Sizing based on submitted data can be performed on request.
Please state: Fluid, density (for liquids), capacity/power, maximum temperature and set pressure
Bar implies bar gauge: bar(ö), bar(g), bar(e), atö or kg/cm2 if nothing else is stated.
Nm3/h implies "free" capacity air/gas (N=normal) and is equal with m3/h if other is not stated.

Lowest set pressure for safety valves with soft sealing disc is 1,0 barg.

Coefficient of discharge steam/gas, αd D/G
0,7

Coefficient of discharge liquids, αd F
0,45

Flow diameter Do, see table Dimension and Weight.

Sizing DN20-50

DN 20 25 32 40 50
Seat18 mm 23 mm 29 mm 37 mm 46 mm
Pset

bar

SteamAirWaterSteam AirWaterSteam Air WaterSteam Air WaterSteam Air Water
0,2 93 1103544 152 1805789 241 2879200393 46615000608 72023111
0,5 144 1775011 236 2898189 374 46013000610 74821222943 115632778
1 210 2636789 342 43011078 544 68417667887 1111286671367 171144333
2 336 4279600 548 69715667 870 1108248891411 1800405562189 277862667
3 451 58011778 737 94719222 1167 1500305561900 2444496672944 377876778
4 563 72813556 919 117822111 1456 1889352222378 3067573333667 474488667
5 674 87615222 1100 142224778 1744 2267394442844 3700641114400 571199111
6 784 102416667 1278 166727111 2033 2656431113311 4322702225122 6689108556
7 896 116718000 1456 191129333 2322 3033466673778 4944758895844 7656117778
8 1006 131119222 1633 215631333 2600 3422497784244 5578811116567 8622125556
9 1111 146720333 1811 238933222 2889 3811528894711 6200860007278 9589133333
10 1222 161121444 2000 263335000 3178 4189556675178 6833906678000 10556140000
12 1440 191123556 2356 312238444 3744 4967610006100 8078993339433 12444153333
14 1656 220025444 2711 360041444 4322 5733658897033 933310733310867 14333165556
16 1878 250027111 3078 408944333 4889 6500704447967 1058911444412222 16333177778
18 2100 280028778 3433 456747000 5456 7267747788889 1177812222213667 18222187778
20 2322 308930333 3789 505649556 6033 8044787789822 1300012777815111 20222197778
22 2544 338931889 4156 554452000 6611 88118266710756 1433313444416556 22111207778
24 2767 368933222 4522 602254333 7189 95788633311667 1555614000018000 24111216667
26 2989 398934556 4878 651156556 7767 103448988912556 1677814666719444 26000225556
28 3211 427835889 5244 698958667 8344 111119322213556 1800015222221000 27889234444
30 3433 457837222 5611 747860667 8922 118899644414444 1933315666722444 29889243333
32 3656 487838444 5978 795662667 9511 125569966715444 2055616222223889 31778251111
34 -516739556 -844464667 -13333102778-21778167778-33778258889
36 -546740778 -893366444 -14111105667-23111172222-35667265556
38 -576741889 -941168333 -14889108556-24333176667-37667273333
40 -605642889 -990070111 -15667111111-25556181111-39556280000
Pset = set pressure
According to applied standards the value above should be multiplied with the safety factor 0,9.
Saturated steam in kg/h. Air in Nm3/h (free air) at 0ºC and atmospheric pressure 1013 mbar(a). Water in kg/h at 20ºC.
Capacities are given for an overpressure of 10% of set pressure.
Contact Armatec for sizing with other fluids etc.

Sizing DN65-100

DN 65 80 100
Seat60 mm 74 mm 92 mm
Pset
barSteamAirWaterSteamAir WaterSteam Air Water
0,2 1033 1222393331567 1856598892422 287892556
0,5 1600 1967556672433 2989847783767 4622131111
1 2322 2922754443544 44441144445478 6878177778
2 3722 47331066675667 72111622228756 11111251111
3 5011 64331311117622 978919888911778 15111306667
4 6244 80781511119511 1222222888914667 19000354444
5 7489 973316888911333 1477825666717556 22778396667
6 8711 1133318444413222 1722228111120444 26667434444
7 9944 1300020000015111 1977830333323333 30556468889
8 11111 1466721333316889 2222232444426222 34444501111
9 12333 1622222666718778 2477834444429111 38333532222
10 13556 1788923888920667 2733336222232000 42222561111
12 16000 2122226111124333 3233339777837667 49889614444
14 18444 2455628222228111 3733342888943444 57667663333
16 20889 2777830111131778 4233345888949222 65444708889
18 23333 3111132000035556 4733348666755000 73222752222
20 25778 3433333777839222 5233351333360667 80889793333
22 28222 3766735333343000 5733353777866556 88667831111
24 30778 4100037000046778 6233356222272333 96444868889
26 33222 4422238444450556 6733358444478222 105556904444
28 35667 4755639888954333 7233360666784000 113333937778
30 38222 5088941333358111 7744462777889889 121111971111
32 40667 5411142666761889 8244464888995778 1288891003333
34 -57444440000-88556668889-1366671034444
36 -61556452222-93667687778---
38 -64889464444-98778706667---
40 -68222476667-103889725556---
Pset = set pressure
According to applied standards the value above should be multiplied with the safety factor 0,9.
Saturated steam in kg/h. Air in Nm3/h (free air) at 0ºC and atmospheric pressure 1013 mbar(a). Water in kg/h at 20ºC.
Capacities are given for an overpressure of 10% of set pressure.
Contact Armatec for sizing with other fluids etc.

Sizing DN125-200

DN 125 150 200
Seat98 mm 125 mm 165 mm
Pset
barSteamAir Water Steam Air Water Steam Air Water
0,2 2756 3267 105111 44785311 171111 78119267 255555
0,5 4278 5244 148889 69568533 242222 1211114778 403333
1 6211 7811 201111 1011112667 327778 1755522111 570000
2 9933 12556 284444 1611120556 463333 2811135778 806667
3 13333 17111 348889 2166727889 566667 3788948667 987778
4 16667 21556 402222 2711135000 654444 4722261111 1144444
5 19889 25889 450000 3244442222 732222 5655573555 1277778
6 23222 30333 493333 3777849333 802222 6588986000 1400000
7 26444 34667 532222 4311156444 865556 7522298444 1511111
8 29778 39111 568889 4844463667 925556 84444110889 1611111
9 33000 43444 603333 5377870778 982222 93667123333 1711111
10 36222 47889 636667 5900077889 1035556 102889135555 1800000
12 42778 56667 696667 6966792222 1133333 121111160000 1977778
14 49333 65444 753333 80222106556 1222222 138889185555 2133333
16 55889 74222 804444 90889120000 1300000 157778210000 2277778
18 62333 83000 853333 101556134444 1377778 176667238889 2422222
20 68889 91778 900000 111111148889 1455556 195555263333 2555555
22 75444 100667 943333 123333165556 1533333 214444288889 2677778
24 82111 110889 985556 133333180000 1600000 232222314444 2788889
Pset = set pressure
According to applied standards the value above should be multiplied with the safety factor 0,9.
Saturated steam in kg/h. Air in Nm3/h (free air) at 0ºC and atmospheric pressure 1013 mbar(a). Water in kg/h at 20ºC.
Capacities are given for an overpressure of 10% of set pressure.
Contact Armatec for sizing with other fluids etc.
For larger DN and/or higher capacities see separate product data sheet AT 4543-4580, DN 200-400.

Accessories and Options

Test Gag for blocking the safety valve
Lift stopper
Soft sealing O-ring of Kalrez (FFKM) C for temperature range 0-250 oC.
Heating jacket.
Open lifting device.
Flanges drilled acc. to ANSI.
With stainless steel bellows series AT 4547-4584.
Open bonnet, see product data sheet AT 4550.

Installation

ConnectionsFlanges drilled according to
AT 4541/AT 4542
Inlet/outletDN25-80: DIN EN 1092-1, PN40 / DIN EN 1092-1, PN16

DN100-150: DIN EN 1092-1, PN16 / DIN EN 1092-1, PN16

DN200: DIN EN 1092-1, PN25 / DIN EN 1092-1, PN10
See separate installation instruction. The valve should be mounted with the bonnet in vertical position.

Installation 4543-4581

Art. no.Flanges drilled according to
AT 4543/AT 4545
Inlet/ouletDN20-150: DIN EN 1092-1, PN40 / DIN EN 1092-1, PN16
DN200: DIN EN 1092-1, PN25 / DIN EN 1092-1, PN16

See separate installation instruction. The valve should be mounted with the bonnet in vertical position.

Maintenance and Spare parts

See separate installation and maintenance instruction.

Marking

Manufacturer, Armatec article number, DN, PN, CE-marking, material and arrow showing the flow direction.
TÜV approval label with manufacturer fig. no. 441 mounted on body.
Set pressure is punched on the outlet flange and on the TÜV approval label.

How to order

Metal seated safety valve
Example: AT 4543-4-5,0-25
AT 4543-4-5,0 -25
Fig. no.DesignSet pressure (barg)DN
AT 4541=nodular iron-2=gas tight cap

AT 4543=steel-4=gas tight lifting device
AT 4580=stainless steel-3=open lifting device

How to order soft seated valve

Soft seated safety valve
Example: AT 4545D4-5,0-25
AT 4545D4-5,0 -25
Fig. no.O-ringDesignSet pressure (barg)DN
AT 4542=nodular ironD=EPDM2=gas tight cap

AT 4545=steelL=Viton4=gas tight lifting device
AT 4581=stainless steelK=Neoprene3=open lifting device
N=Nitrile