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Safety Valve AT 4522, 4523, 4577, 4578

Safety valve with standard characteristics. Flanged connections. Steel or stainless steel. Soft- or metallic seated disc. DN15-150 (stainless DN15-100), PN16-40. Back pressure compensating bellows of stainless steel.

Dimension range15-150
PN16-40
Temperature range-270 to +450°C
MaterialSteel, stainless steel

Variations

Article number Amount
AT 4522
AT 4523
AT 4577
AT 4578

Product information

Main facts

Dimension rangePNTemperature rangeMaterial
DN 15-15040-85ºC to +450 ºCSteel
DN 15-10040-270ºC to +400 ºCStainless steel

Range of Application

Safety valve for protection of pressure vessels and piping systems with liquids, air, gases and steam. Suitable as safety valve also when back-pressure is varying. Provided with back-pressure compensating and sealing stainless steel bellows.

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 4522/AT 4523 AT 4577/AT 4578

1

Body 1.0619/SA 216 WCB1.4408/SA 351 CF8M
2Seat 1.4404/316L 1.4404/316L
3 Disc1.4122/Hardened stainless steel1.4404/316L
4 Spindle1.4404/316L1.4404/316L
5 Spring1.1200,1.8159,1.7102/Spring steel1.4310/Stainless steel
6 Bellows1.4571/316Ti 1.4571/316Ti
Bonnet spacer1.4404/316L1.4404/316L
7 Guide1.4104,1.0501,1.0570/Chrome- or stainless steel1.4404/316L
Bushing for guide1.4104 tenifer/Chrome steel-
8 Bonnet1.7040/Nodular iron Gr.60-40-18 1.4408,1.4404/
SA 351 CF8M,SA 479 316L
9 Spring plate 2 pcs1.0718/Steel1.4404/316L
10 Adjusting screw1.4104 PTFE/Chrome steel PTFE1.4404 PTFE/316L PTFE
11 Ball1.3541/Hardened stainless steel1.4401/316
12Cap1.0718/12L131.4404/316L
13Soft sealEPDM (D)EPDM (D)
13Soft sealNeoprene (K) Neoprene (K)
13Soft sealViton® (L) Viton® (L)

Dimension and Weight

AT4522, 4523
DN 1520253240506580100125150
Flow diameter1218181823293746607492
A (4)272250250255275300390445505625740
B9095100105115125145155175200225
C150150150200200250250300350400450
Weight6,36,46,48,49,6131621,635,652,178,4
Measurements in mm, weight in kg. (4)= with gastight lifting device

Dimension and Weight

AT 4577, 4578
DN 1520253240506580100
Flow diameter121818182329374660
A (4)272250250255275300390445505
B9095100105115125145155175
C150150150200200250250300350
Weight6,36,46,48,49,6131621,635,6
Measurements in mm, weight in kg. (2)= with gas tight cap (4)= with gas tight lifting device

Function and Design

Spring loaded and directly acting safety valve with standard characteristics, with stainless steel bellows. The bellows can compensate for varying back-pressure up to around 35 % of the set pressure. In addition, the bellows protect the moving parts against dirt, corrosion and temperature. 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 10 %.
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
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 pressure is requested please contact Armatec

Pressure and temperature

AT 4522/AT 4523 AT 4577/AT 4578
Set pressureTemp. Set pressure- Temp.
max. -85°C tomax. -270°C to
DNbar +450°Cbar +400°C
15 40 40
20 40 40
25 40 40
32 40 40
40 40 40
50 40 40
65 40 26
80 35 25
100 3022
125 32-
150 16 -
Pressure and temperatures according to applied standards for each valve material.
At temperatures above 200 oC 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; AT 4523 and 4578
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
DN15 metal to metal: 0,62
DN15 soft sealed: 0,59
DN20: 0,29
DN25-150: 0,38

Coefficient of discharge liquids αd F
DN15 metal to metal: 0,48
DN15 soft sealed: 0,47
DN20: 0,19
DN25-150: 0,25


Flow diameter, Do see Dimension and weight.

Sizing DN15-50

DN 15 15 20 25+32 40 50
SeatMet. 12mm Soft 12mm18mm 18mm 23mm 29mm

Pset

barSteamAirWaterSteam AirWaterSteam AirWaterSteam AirWaterSteam AirWaterSteam AirWater
0, 2 36 431678 35 411633 1 11500 32 381967 53 633211 84 995111
0, 5 57 702378 54 662333 32 392111 68 842789 111 1374544 177 2177233
1 81 1023222 77 973156 72 902867 106 1333767 173 2186156 277 3479789
2 128 1634556 121 1564467 133 1704056 178 2275333 290 3708711 461 58813889
3 172 2215578 163 2105467 184 2374967 240 3096533 392 50410667 624 80217000
4 214 2786433 203 2646300 233 3015733 306 3967544 499 64612333 793 102619556
5 257 3337200 - 3177056 279 3636411 366 4765100 598 77713778 950 123321889
6 299 3907878 - 3707722 326 4247022 426 5569233 696 90815111 1106 143324000
7 341 4478511 - 4248344 371 4867578 486 6379978 793 103916333 1256 164425889
8 383 5039100 - 4788922 417 5478111 546 71710667 891 116717444 1411 185627667
9 426 5609656 - 5329467 462 6098600 606 79811333 989 130018444 1567 206729333
10 467 61710178 - 5869978 508 6709067 666 87811889 1087 143319444 1722 227831000
12 551 72911111 - 69210889 599 7939922 784 103913111 1278 168921333 2033 268933889
14 634 84212000 - 80011778 690 91610722 904 118914111 1467 195623000 2344 311136667
16 718 95412889 - 90712667 781 103911444 1023 135615111 1667 221124667 2656 352239111
18 802 106813667 - 101413444 872 115612111 1133 151116000 1856 247826111 2967 394441556
20 887 117814444 - 112214111 963 127812778 1256 167816889 2056 274427556 3278 436743778
22 971 128915111 - 122214778 1056 140013444 1378 183317667 2256 300028889 3589 477845889
24 1056 140015778 - 133315444 1144 152214000 1500 200018444 2444 326730111 3900 520048000
26 1133 151116444 - 143316111 1233 164414667 1622 215619222 2644 353331444 4211 561149889
28 1222 162217000 - 154416667 1322 176715111 1744 232220000 2844 378932556 4522 603351778
30 1300 174417667 - 165617333 1422 188915667 1867 247820667 3044 405633667 4844 645653556
32 1389 185618222 - 176717889 1511 201116222 1989 264421333 3244 432234778 5156 686755333
34 - 196718778 - 186718444 -213316667 -280022000 -457835889 -728957111
36 - 207819333 - 197819000 -226717222 -296722667 -484436889 -770058778
38 - 218919889 - 207819444 -238917667 -312223222 -511138000 -812260333
40 - 230020333 - 218919889 -251118111 -328923889 -536738889 -854461889
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 DN65-150

DN 65 80 100 125 150
Seat37mm 46mm 60mm 74mm 92mm
Pset
barSteamAirWaterSteamAirWaterSteam Air WaterSteam Air WaterSteamAir Water
0,2 137 1628322 2112501288935942621889547647 333338441001 51444
0,5 288 35311778 446546182227589293088911441411 4711117782178 72778
1 450 56415889 69487324667117814784188917892256 6377827783489 98556
2 751 95722556 1156147834778196725115922230003822 9011146445911 138889
3 1016 130027556 1567201142667266734227255640565211 11033362788067 171111
4 1289 166731889 1989257849222338934228377851566667 127778797810311 196667
5 1544 200035667 2389310055111405643899366761788033 142222955612333 220000
6 1800 234439000 27783622603334733527810266772009389 1555561111114444 241111
7 2044 268942111 316741566511154006178110889821110756 1688891266716556 261111
8 2300 302245111 355646786966760567067118889922212111 1800001422218667 278889
9 2556 336747778 3944520073889672279671255561023313444 1911111577820778 295556
10 2811 370050333 4344573377889738988561322221122214778 2011111733322889 311111
12 3311 438955222 5122677885333871197441455561322217556 2211112044427111 341111
14 4322 506759667 590078339211110044114441566671522220222 2388892355631333 368889
16 4822 574463778 667888789855611333132221677781722223000 2544442666735444 394444
18 5333 642267556 7456993310444412667151111777781922225667 2700002988940222 417778
20 5844 710071222 82441098911011114000168891877782133328333 285556---
22 6344 778974778 90331200011555615333186671966672333331111 298889---
24 6856 846778000 98111300012111116667204442055562533333778 312222---
26 7367 914481222 10600141111255561800022222213333------
38 7889 982284333 11333151111300001933324000222222------
30 8400 1050087222 12111162221344442066725778230000------
32 -1111190111 12889172221388892200029333236667------
34 -1177892889 -18333143333-31667244444------
36 ----19667147778-33444251111------
38 ----20667152222---------
40 ----21778155556---------
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.

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.

Installation

ConnectionFlanges drilled acc. to
AT 4522/AT 4523 AT 4577/AT 4578
InletDIN EN 1092-1, PN40DIN EN 1092-1, PN40
OutletDIN EN 1092-1, PN40DIN EN 1092-1, PN40

See separate installation instruction. The valve should be mounted with the bonnet in vertical position. The stainless steel bellows has a connection for drainage piping or for leak detection piping (which can show if the bellows are broken). Mounted protection plug is removed and replaced on site with appropriate device.

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 stainless steel bellow
Example: AT 4522-4-5,0-25
AT 4522-4-5,0 -25
Fig. nodesignSet pressure (barg)DN
AT 4522=steel-2=gas tight cap

AT 4577=stainless steel-4=gas tight lifting device

How to order AT 4523

Soft seated safety valve with stainless steel bellow
Exempel: AT 4523D4-5,0-25
AT 4523D4-5,0 -25
Fig.no.O-ringDesignSet pressure (barg)DN
AT 4523=steelD=EPDM2=gas tight cap

AT 4578=stainless steelL=Viton4=gas tight lifting device
K=Neoprene
N=Nitrile