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Safety Valve AT 4547, 4548, 4583, 4584

Full lift safety valve. Flanged connections. Steel or stainless steel. Soft- or metallic seated disc. DN20/40-200/300 (stainless DN25/40-150/250), PN40. Back-pressure compensating bellows of stainless steel.

Dimension range20-200
PN40
Temperature range-270 to +450°C
MaterialSteel, stainless steel

Variations

Article number Amount
AT 4547
AT 4548
AT 4583
AT 4584

Product information

Main facts

Dimension rangePNTemperature rangeMaterial
DN 20-15040-85°C to +450 ºC Steel
DN 20025-85°C to +450 ºC Steel
DN 20-15040-270°C to +400 ºCStainless steel
DN20025-270°C to+400 ºCStainless steel

Range of Application

Safety valve for protection of pressure vessels and piping systems with liquids, air, gases and steam.
Provided with back-pressure compensating and sealing stainless steel bellows. This raises the maximum allowable back-pressure in the outlet from 15 % to 30-35 % of the set pressure. The design pressure of the bellows must however be taken into account. See Additional information.
With back-pressure compensating bellows, the outlet dimension can be kept down.
Bellows are also recommended when the safety valve is to be connected to a silencer.


Program text

PSG. 11 Safety valve
Safety valve with back pressure compensating bellows AT4547, DN ..., set pressure... bar, stainless steel.

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 4547/AT 4548 AT 4583/AT 4584
1 Body 1.0619/SA 216 WCB, steel1.4408/SA 351 CF8M, stainless steel
2 Seat1.4404/316L1.4404/316L
3 Disc 1.4122/hardened stainless steel1.4404/316L
4 Spindle 1.4021/4201.4404/316L
5 Spring1.1200, 1.8159, 1.4310/stainless steel
1.7102/carbon steel
6 Bellows1.4571/316Ti1.4571/316Ti
7 Guide1.4104, 1.0501, 0.7040/1.4404/316L
chrome- or carbon steel
8 Bonnet0.7040, 0.7043, 1.0619/1.4408, 1.4404, 1.4571/
nodular iron Gr.60-40-18,SA 351 CF8M, SA 479 316L,
SA 216 WCBSA 479 316Ti
9 Spring plate 2 pcs1.0718/steel1.4404/316L
10 Adjusting screw1.4104 PTFE/1.4404 PTFE/316L PTFE
chrome steel PTFE
11 Ball1.3541/hardened stainless steel1.4401/316
12aCap1.0718 or 0.7043/12L13 1.4404/316L
or Gr.60-40-18
12bLever (4) 1.0718 or 0.7043/12L13 1.4404/316L
or Gr.60-40-18
13aSoft sealingEPDM (D)EPDM (D)
13bSoft sealingNeoprene (K) Neoprene (K)
13cSoft sealingViton® (L) Viton® (L)
14 Bonnet spacer1.0460/ carbon steel1.4404/316L
for bellow

Dimensions and weight

AT 4547, 4548
DN Inlet20253240506580100125150200
DN Outlet4040506580100125150200250300
Seat diameter182329374660749298125165
A 2522733734104655996657197198561090
B95100110115120140160180200225300
C85105115140150170195220250285290
D150150200250300350400450450450700
Weight9,41013172436608393142289
Measurements in mm, weight in kg.
(2)= gas tight cap, (4)= gas tight lifting device.

Dimension and weight AT 4583-4584

AT 4583, 4584
DN Inlet253240506580100125150
DN Outlet4050658010025150200250
Flow diameter2329374660749298125
A max273373410465599665719719856
B100110115120140160180200225
C105115140150170195220250285
D150200250300350400450450450
Weight1013172436608393142
Measures in mm, weights in kg.
(2)= gastight cap (4)= gastight lifting device.

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 normal 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.
The bellows protect the moving parts and spring against dirt, corrosion and temperature, and permit an increased maximum back-pressure in the outlet pipe from 15 % to 30-35 % of the set pressure.
The bellows design pressure must be considered. See Additional information.

Technical Information

Overpressure
The safety valve is fully open at an overpressure exceeding the set pressure with a maximum of 5 % (for liquids, 10 %).
If lower overpressure is requested please contact Armatec.

Blowdown

Blowdown

Blowdown

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

Pressure and temperature

AT 4547/AT 4548 AT 4583/AT 4584
Set pressure max. Temp. -85°CSet pressure max. Temp. -85°C
DNbar to +450°Cbar to +400°C
20 40 -
25 40 40
32 40 40
40 40 40
50 40 37
65 40 28
80 4025
100 40 26
125 25 24
150 2510
200 25 -
Pressure and temperatures according to applied standards for each valve material.
At temperatures above 200°C 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.

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

Coefficient of discharge liquids, αd F
0,45

Flow diameter Do, see Dimension and Weight

Lowest set pressure for valve with bellows:
3,0 barg (DN20-80)
2,74 barg (DN100)
2,01 barg (DN125)
0,2 barg (DN150-200)

Design pressure for stainless steel bellows

Max. pressure bar At 20°CAt 100°CAt 200°CAt 400°C
DN2030282420
DN2516151311
DN32-125109,386,6
DN15065,64,84
DN20054,743,3

Sizing DN20-50

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

bar

SteamAirWaterSteamAirWaterSteamAirWaterSteamAirWaterSteamAirWater
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
barSteamAirWaterSteamAirWaterSteamAirWater
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
barSteam AirWaterSteam Air WaterSteamAir 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 valve dimensions and/or larger capacities, se separate data sheet for
AT 4543 - 4580, DN 200-400 are available with bellows on request.

Accessories and Options

Test Gag for blocking the safety valve
Lift stopper
Soft sealing O-ring of Kalrez (FFKM) C for temperature range 0-250oC.
Flanges drilled acc. to ANSI.
For safety valve without bellows, see product data sheet AT 4541 and AT 4550.

Installation

Connection AT4547/4548Flanges drilled acc. to
Inlet/outletDN20-150: DIN EN 1092-1, PN40/16
DN200: DIN EN 1092-1, PN25/16
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. 433 mounted on body.
Set pressure is punched on the outlet flange and on the TÜV approval label.

How to order

Metal seated safety valve with back-pressure compensating bellows.
Example: AT 4547-4-10,0-25
AT 4547-4-10,0 -25
Fig. no.DesignSet pressure(bar)DN
AT 4547=steel-2=gas tight cap

AT 4583=stainless steel-4=gas tight lifting device
-3=open lifting device

How to order 4548D

Soft seated safety valve with back-pressure compensating bellows.
Example: AT 4548D4-10,0-25
AT 4545D4-10,0 -25
Fig. no.O-ringDesignSet pressure (bar)DN
AT 4548=steelD=EPDM2=gas tight cap

AT 4584=stainless steelL=Viton4=gas tight lifting device
K=Neoprene3=open lifting device
N=Nitrile