Pressure reducing valves Index

Transcription

1 Index General information page Introduction 506 General introduction 507 for a steam plant 509 Product information BSP thread page Brass 510 ; BSP female thread 511 ; BSP male thread 513 Stainless steel ; BSP female thread; igh pressure 514 page Bronze 515 ; Flanges PN ; Flanges PN Cast iron ; Flanges PN Ductile cast iron 519 ; Flanges PN 25; Max. 70 C 520 ; Flanges PN 25; Max. 350 C 521 Steel ; Flanges PN Stainless steel ; Flanges PN ; igh pressure 523 Index and product compare Pressure reducing valves and safety valves FA-001 page 505

2 Pressure reducing valves Condensate vessel Flanges: DIN or ASME BSP or NPT thread Seat Disc Material of body brass bronze ductile cast iron steel stainless steel Bellows Spring plate Tail piece Spring steel stainless steel Venting plug Spring plate Impulse line Control simple diaphragm bronze or SS bellows servo valve set diaphragm chamber Bellows Pressure reducing valves and safety valves FA-002 page 506

3 General introduction Self-operating pressure reducing valves are fittings that can sufficiently restrict the medium (steam, compressed air, water, etc.) so that the secondary pressure is reduced, without the use of auxiliary energy. Pressure reducing valves are often used to protect the downstream section of the installation from excessive pressure. The following process data is important when selecting a pressure reducing valve: medium temperature capacity (*) upstream pressure downstream pressure (*) gases are compressible, so it is important with the capacity to indicate what pressure is present. Background A differential pressure produces a flow of a medium and the velocity depends on this differential pressure (dp). A higher velocity arises through a higher differential pressure and a higher pressure loss is the results of a higher velocity. The relationship between differential pressure (loss) and velocity can be expressed as dp = v². Because velocity is squared in this equation, it is clear that a small increase in velocity has a significant influence on the pressure drop. When a medium flows through a pipe, the flow rate (Q) depends on the velocity (v) and surface (A) of the pipe cross-section: Q(m ) = A(m ) x v(m/s) Should the same quantity flow also through a smaller bore, this means that the velocity at that point will be higher. The flow rate in a pressure reducing valve is increased or decreased by making the valve opening smaller or larger. Velocity for gases, including steam, cannot be increased indefinitely. There is an upper limit, at which the velocity will no longer increase. This velocity is referred to as critical velocity and occurs at the so-called critical pressure drop (p2 = 0.58 x p1). A further drop of the downstream pressure p2 can only be achieved by enlarging the pipe following the pressure reducing valve. Common practice with gases is for the pipe diameter after the pressure reducing valve to be greater than the diameter before it. The self-operating pressure reducing valves can be divided into two variants, being: 1) direct-acting 2) indirect-acting 1) variant This is usually a simple pressure reducing valve in which spring pressure produces the required downstream pressure directly. 2) Indirect-acting variant This is a pressure reducing valve in which the spring pressure first actuates a servo valve. The servo valve subsequently actuates the main valve, which ensures that the required downstream pressure is achieved. Strainer It is recommended to install a strainer before each pressure reducing valve. This strainer will safeguard the pressure reducing valve against contamination carried along in the pipe, such as rust particles, welding debris and mill skin of the pipe. The strainer element already built into some pressure reducing valves then functions as extra protection. Globe valve It is recommended to fit a globe valve before and after the pressure reducing valve. If required a pressure reducing valve can then easily be replaced and/or overhauled. In exceptional circumstances the use of a bypass valve can ensure uninterrupted duty. Pressure gauge To be able to adjust pressure reducing valves and check for the proper functioning it is recommended to fit a pressure gauge before and after each pressure reducing valve. The actual prevailing pressure can be read out using pressure gauges. Safety Because pressure reducing valves are subject to wear and tear, it is recommended to fit a safety valve after each pressure reducing valve. This safety valve will safeguard the following system from excessive pressure. In some situations (e.g. steam installation), the installation of a safety device is even compulsory, if the equipment following the reduction cannot or may not be subjected to the initial pressure. Pressure reducing valves and safety valves FA-003 page 507

4 General introduction Capacity chart FOW VEOCITY in m/s DN 8 (1/4") DN 10 (3/8") DN 15 (1/2") DN 20 (3/4") DN 40 (1 1/2") DN 25 (1") DN 32 (1 1/4") DN 50 (2") DN 65 DN 80 DN 100 DN 125 DN 150 DN 200 DN 250 Figure B 141GYP 141NOD , CAPACITY in m3/hour Water Compressed air Calculation example for air A pressure reducing valve is required for compressed air from 8 to 2 bar, with a capacity of 30 m3 standard volume (volume at 0 C and kpa). The 30 m3 standard volume should first be converted to m3, at the downstream pressure (in bar abs). In this case: 30/(2 + 1) = 10 m3/hour. For compressed air, from 10 m3/hour on the horizontal axis, go up to the intersection with the compressed air line for DN ", at a velocity of 15.7 m/sec. Calculation example for water A pressure reducing valve for water with a capacity of 10 m3/hour is required. From 10 m3/hour on the horizontal axis go upwards and from 1.5 m/sec. on the vertical axis, locate an intersection. This results in the choice for a pressure reducing valve with a DN 50 connection. Application index Figure B GYP 141NOD Medium Water iquids Steam Compressed air Nitrogen Other Pressure reducing valves and safety valves FA-004 page 508

5 for a steam plant A steam installation: Below you will find a possible set-up of a pressure reducing valve in a steam installation. For the design of the so-called pressure reducing installation the, following aspects are to be considered: A steam pipe should be installed on a fall of 3-5 mm per metre. Econosto recommends a dripleg every meters, by means of a trap set. Econosto recommends branching the main steam pipe from the top of the pipe. For pressure reducing valves and control valves Econosto recommends installing a water separator and a strainer. This extra protection will extend the service life of a pressure reducing valve or control valve. According to Stoomwezen/loyd's Register a spring-loaded safety valve should be fitted behind each pressure reducing valve (in a steam installation). The method of determining the size of the spring-loaded safety valve is described in the Netherlands Steam Act. When ordering a spring-loaded safety valve, the set pressure is to be indicated. The set pressure should always be higher than the normal operating pressure. Also refer to section safety valves. Econosto recommends using the Spiratec system to monitor steam traps in a steam installation. G D E J A B C I F FITER SPIRATEC STEAM TRAP A Water separator B Valve (fig. 430 or fig. 436) C Filter (fig or fig. 1124) D Pressure gauge set (fig. 334 pressure gauge) (fig siphon) (fig. 862 pressure gauge valve) E Pressure reducing valve (fig. 1908) F Valve (fig. 430 or fig. 436) G Bypass valve (fig. 430 or fig. 436) Safety valve (fig. 567) I Valve in impulse line (fig. 251) J Pressure gauge set (fig. 334 pressure gauge) (fig siphon) (fig. 862 pressure gauge valve) Remark Besides these specified figure numbers, other figure numbers can be applied for other materials. Pressure reducing valves and safety valves FA-005 page 509

6 BSP thread Brass Index and product compare page 511 page 512 page 513 BSP female thread Compressed air and gases " - 2" Max. 70 C Max. 40 bar Range 1-10 bar BSP female thread Water " - " Max. 70 C Max. 16 bar Range bar Brass dezincification resistant BSP male thread Water, compressed air and nitrogen " - 2" Max. 70 C Max. 25 bar Range bar DVGW approval (fig. 143) KIWA approval (fig. 143) Pressure reducing valves and safety valves FA page 510

7 BSP thread Brass Simple, efficient pressure reducing valve, in which the pressure spring does not contact the medium. Purpose: compressed air and other non-hazardous gases. Max. inlet pressure and temperature 40 bar - 70 C Minimum differential pressure 1 bar Downstream pressure range 1-10 bar BSP female thread connection Component Material Body and cover Brass Disc guide Brass Spring cap Plastic Diaphragm NBR Disc sealing ring NBR O-ring NBR Accessories Pressure gauge with bottom connection (e.g. fig. 334, case diameter 63 mm) Install in a horizontal pipe, with spring cap underneath BSP female thread fig. 142 Compressed air and gases " - 2" Max. 70 C Max. 40 bar Range 1-10 bar Remark The picture shows the execution for the sizes " - ". The sizes 1" - 2" are without knob. Capacity See capacity chart in the introduction of this section Ordering code Reduced pressure range DN [bar] ["] h Fig. DN h Weight Kvs-value ["] [mm] [kg] [m3/hour] Pressure reducing valves and safety valves FA page 511

8 BSP thread Brass Compact pressure reducing valve designed for small installations (households). Due to the design this pressure reducing valve is suitable for low capacities and the medium does not contact the spring. Purpose: water. Max. inlet pressure and temperature 16 bar - 70 C Minimum differential pressure 1 bar Downstream pressure range bar BSP female thread connection Component Material Body, disc and seat Brass Spring Stainless steel Diaphragm NBR O-ring NBR Accessories Pressure gauge with bottom connection (e.g. fig. 334, case diameter 50 mm) Install in a horizontal pipe, with spring cap above BSP female thread fig. 152 Water " - " Max. 70 C Max. 16 bar Range bar Brass dezincification resistant Ordering code Reduced pressure range DN [bar] ["] DN Fig. DN 1 Weight Kvs-value ["] [mm] [kg] [m3/hour] Pressure reducing valves and safety valves FA page 512

9 BSP thread Brass Reliable pressure reducing valve, provided with strainer element (mesh size 0.16 mm). The valve is constructed as a single seat balanced disc. The synthetic trim makes this type resistant to corrosion and cavitation. The construction gives especially low-noise operation. The spring cap is provided with a pressure indication. Purpose: water, other non-aggressive liquids, compressed air and nitrogen. Max. inlet pressure and temperature 25 bar - 70 C Minimum differential pressure 1 bar Downstream pressure range bar bar Couplings with BSP male thread connection Component Body and couplings Spring cap, adjustment knob, disc and seat Diaphragm and gaskets Strainer Material Brass Plastic NBR Stainless steel Special variants For higher downstream pressures: max. 12 bar. Pressure reducing valve provided with an extra large add-on filter (perforation size 0.1 mm) for water application. The add-on filter is also separately. Accessories Pressure gauge with rear connection (e.g. fig. 1334, case diameter 63 mm) Extra large add-on filter BSP male thread fig. 143 fig. 148 Water, compressed air and nitrogen " - 2" Max. 70 C Max. 25 bar Range bar DVGW approval (fig. 143) KIWA approval (fig. 143) Install in a horizontal pipe, with spring cap on top See capacity chart in the introduction Ordering code Reduced pressure range Approval DN [bar] ["] DVGW/KIWA Fig. DN l h D Weight Kvs-value ["] [mm] [kg] [m3/hour] D I Fig. 143 h D I Fig. 148 h Pressure reducing valves and safety valves FA page 513

10 BSP thread Stainless steel Entirely stainless steel pressure reducing valve, suitable for vapour, gases and liquids. Due to the applied materials and the high pressure ratio, this pressure reducing valve is suitable for many applications. Max. inlet pressure Downstream pressure range (*) 16 bar bar - 63 bar bar 100 bar bar 63 bar bar bar bar 1 63 bar bar 2 40 bar bar (*) Specified pressure ranges can only be attained by means of changing the spring and/or internals. Pressure ratio Max. pressure ratio = P upstream: P downstream = 40 : 1 Min. pressure ratio = P upstream: P downstream = 1.1: 1 BSP female thread connection Component Material EN and/or (DIN) W.nr. Wetted parts Stainless steel X6CrNiMoTi Other parts Stainless steel X5CrNi O-rings FPM (Viton) Special variants For lower downstream pressure range For higher upstream pressures With NPT female thread connection With other materials for O-rings Smaller connection size BSP female thread igh pressure fig Vapour, gases and liquids " - 2" Max. 200 C Max. 16 to 100 bar Max. pressure ratio 40: 1 Wetted parts : Accessories Pressure gauge with bottom connection (e.g. fig. 334) Cast iron elbow " BSP female thread/male thread (e.g. fig. 841) Install in a horizontal pipe, with spring cap on top Capacity See capacity chart in the introduction of this section Ordering code DN ["] When ordering, specify the following data: - upstream pressure - required downstream pressure ~16 Fig. DN 1 1 Weight Kvs-value ["] [mm] [kg] [m3/hour] DN Pressure reducing valves and safety valves FA page 514

11 Bronze Flanges PN 25 page 516 page 517 Water and compressed air DN Max. 70 C Max. 25 bar Range bar Flanges PN 40 Compressed air DN Max. 75 C Max. 30 bar Setting range bar Max. pressure ratio 6: 1 Index and product compare Pressure reducing valves and safety valves FA page 515

12 Bronze Simple pressure reducing valve with built-in strainer element (mesh width 0.5 mm) for general industrial applications, aboard ships and in the installation industry. The single seated balanced disc guarantees a smooth, low-noise operation. The inlet flange and the outlet flange are both fitted with a " pressure gauge connection. Due to the construction the pressure spring does not contact the medium. Purpose: water, other non-aggressive liquids, compressed air and nitrogen. Maximum upstream pressure Max. inlet pressure and temperature 25 bar - 70 C Minimum differential pressure 1 bar Downstream pressure range bar Flanges rated DIN PN 25 Component Material EN and/or (DIN) W.nr. Body Bronze CuSn5Zn5Pb5-C (G-CuSn5ZnPb (Rg 5)) Spring cap Brass Disc and seat Plastic Diaphragm NBR Disc sealing ring NBR Spring Spring steel Strainer Stainless steel Flanges PN 25 fig. 141B Water and compressed air DN Max. 70 C Max. 25 bar Range bar Special variants For lower downstream pressure range: bar (note: has different dimensions) Accessories Pressure gauge with bottom connection (e.g. fig. 334, case diameter 63 mm) Install in a horizontal pipe, with spring cap on top Capacity See capacity chart in the introduction of this section Ordering code Reduced pressure range DN [bar] [mm] 141B DN 15 - DN 40 Fig. DN A h Weight Kvs-value [mm] [kg] [m3/hour] 141B B B B B h DN A Pressure reducing valves and safety valves FA page 516

13 Bronze Reliable pressure reducing valve for general industrial applications, aboard ships and in the installation industry. The body is provided with a pressure gauge connection on both sides. By means of pressure gauges the actual reduced pressure can be read. Max. inlet pressure and temperature 30 bar - 75 C Minimum differential pressure 1 bar Downstream pressure range bar Flanges rated DIN PN 40 Component Material EN and/or (DIN) W.nr. Body and flanges Bronze CuSn5Zn5Pb5-C (G-CuSn5ZnPb (Rg 5)) Spring cap (DN 15 - DN 25) Brass Spring cap (DN 32 - DN 50) Cast iron Poppet Brass O-rings NBR Special variants BSP threaded connection BSP threaded connection and a setting range of 20 to 45 bar Accessories Pressure gauge with rear connection (e.g. fig. 1334, case diameter 63 mm) Flanges PN 40 fig. 147 Compressed air DN Max. 75 C Max. 30 bar Setting range bar Max. pressure ratio 6: 1 Install in a horizontal pipe, with spring cap on top. The sizes DN 15 through DN 25 can be installed in a vertical pipe, if required. Capacity See capacity chart in the introduction of this section Ordering code Reduced pressure range DN [bar] [mm] DN 15 DN 50 DN A DN 32 - DN 50 DN A Fig. DN A Weight Kvs-value [mm] [kg] [m3/hour] DN 15 - DN 25 Pressure reducing valves and safety valves FA page 517

14 Cast iron Simple pressure reducing valve for general industrial applications, aboard ships and in the installation industry. The single seated balanced disc guarantees a smooth operation. The body is provided with a powder coating and because of the type of construction the spring does not contact the medium. Max. inlet pressure and temperature 16 bar - 70 C Minimum differential pressure 1 bar Downstream pressure range bar DN 50 - DN 150 pressure gauge connection on in- and outlet flange bar DN 200 pressure gauge connection on the body Flanges rated DIN PN 16 Component Material Body Cast iron Spring cap Cast iron Disc (up to DN 150) Brass Disc (DN 200) Steel Disc sealing ring NBR Seat Bronze Diaphragm EPDM Spring Spring steel Flanges PN 16 fig. 141GYP Water, compressed air and nitrogen DN Max. 16 bar Range bar Special type Downstream pressure range: bar (note: has different dimensions) Accessories DN 50 - DN 150 pressure gauge : inlet (M39M-A16), outlet (M39M-A10) DN 200 pressure gauge M07M-A10 Install in a horizontal pipe, with spring cap on top Capacity See capacity chart in the introduction of this section Ordering code Reduced pressure range DN [bar] [mm] 141GYP ; DN 50 - DN 200 Fig. DN A h Weight Kvs-value [mm] [kg] [m3/hour] 141GYP GYP GYP GYP GYP GYP GYP Pressure reducing valves and safety valves FA page 518

15 Ductile cast iron Flanges PN 25 Max. 70 C page 520 page 521 Water, compressed air and nitrogen DN Max. 25 bar Range bar Flanges PN 25 Max. 350 C Steam, gases and liquids DN Max. 25 bar Range bar Max. pressure ratio 25: 1 Index and product compare Pressure reducing valves and safety valves FA page 519

16 Ductile cast iron Simple pressure reducing valve for general industrial applications, aboard ships and in the installation industry. The single seated balanced disc guarantees a smooth operation. The body is provided with a powder coating and because of the type of construction the spring does not contact the medium. Max. inlet pressure and temperature 25 bar - 70 C Minimum differential pressure 1 bar Downstream pressure range bar (DN 50 - DN 150) bar (DN 200) Flanges rated DIN PN 25 Component Material Body Ductile cast iron Spring cap Cast iron Disc (up to DN 150) Brass Disc (DN 200) Steel Disc sealing ring NBR Seat Bronze Diaphragm EPDM Spring Spring steel Accessories Pressure gauge with bottom connection (e.g. fig. 334, case diameter 100 mm) Cast iron elbow " BSP female thread/male thread (e.g. fig. 841) Flanges PN 25 Max. 70 C fig. 141NOD Water, compressed air and nitrogen DN Max. 25 bar Range bar Install in a horizontal pipe, with spring cap on top Capacity See capacity chart in the introduction of this section Ordering code Reduced pressure range DN [bar] [mm] 141NOD ; DN 50 - DN 200 Fig. DN A h Weight Kvs-value [mm] [kg] [m3/hour] 141NOD NOD NOD NOD NOD NOD NOD Pressure reducing valves and safety valves FA page 520

17 Ductile cast iron Precise and reliable pressure reducing valve, with pressure relief and sealing by stainless steel bellows, for various industrial applications. A great downstream pressure range is achievable thanks to 5 actuators and 3 springs. For applications with a temperature higher than 100 C, the a water sealpot is required. Purpose: steam, gases and liquids. Temperature ( C) PN bar 25 bar 23 bar 21.8 bar 20 bar 17.5 bar Pressure range Actuator Spring No bar DMA bar DMA bar DMA bar DMA bar DMA bar DMA Component Material Body and flanges Ductile cast iron Disc, seat and bellows Stainless steel Spring Steel Gaskets Graphite Actuator DMA M [mm] B [mm] Flanges PN 25 Max. 350 C fig Steam, gases and liquids DN Max. 25 bar Range bar Max. pressure ratio 25: 1 Condensate vessel Actuator Size D [mm] [mm] V [dm3] DMA DMA Install in a horizontal pipe with the actuator directed downwards Capacity Capacity chart on request Ordering code Reduced pressure range DN [bar] [mm] ) DN 15 DN 100 1) Reduced pressure range bar bar bar 2-5 bar bar 8-16 bar A DN Fig. DN A DMA 40 DMA 80 DMA 160 DMA 250 DMA 400 Kvs-value Max. G G G G G dp [mm] [kg] [mm] [kg] [mm] [kg] [mm] [kg] [mm] [kg] [mm] [m3/hour] [bar] G = weight B M Pressure reducing valves and safety valves FA page 521

18 Steel Precise and reliable pressure reducing valve, with pressure relief and sealing by stainless steel bellows, for various industrial applications. A great downstream range is achievable thanks to 5 actuators and 3 springs. For applications with a temperature higher than 100 C, the use of a water sealpot is required. Purpose: steam, gases and liquids. Temperature ( C) PN bar 36.9 bar 30.2 bar 28.4 bar 25.8 bar 24 bar Pressure range Actuator Spring No bar DMA bar DMA bar DMA bar DMA bar DMA bar DMA Component Material Body and flanges Steel Disc, seat and bellows Stainless steel Spring Steel Gaskets Graphite Actuator DMA M [mm] B [mm] Flanges PN 40 fig Steam, gases and liquids DN Max. 350 C Max. 40 bar Range bar Max. pressure ratio 25: 1 Condensate vessel Actuator Size D [mm] [mm] V [dm3] DMA DMA Install in a horizontal pipe with the actuator directed downwards Capacity Capacity chart on request Ordering code Reduced pressure range DN [bar] [mm] ) DN 15 DN 100 1) Reduced pressure range bar bar bar 2-5 bar bar 8-16 bar A DN Figure DN A DMA 40 DMA 80 DMA 160 DMA 250 DMA 400 Kvs-value Max. G G G G G dp [mm] [kg] [mm] [kg] [mm] [kg] [mm] [kg] [mm] [kg] [mm] [m3/hour] [bar] G = weight B M Pressure reducing valves and safety valves FA page 522

19 Stainless steel Entirely stainless steel pressure reducing valve, suitable for vapour, gases and liquids. Due to the applied materials and the high pressure ratio, this pressure reducing valve is suitable for many applications. Max. inlet pressure Downstream pressure range (*) DN bar bar DN bar bar DN bar bar DN 25 DN bar bar DN bar bar DN bar bar DN 65 DN bar bar (*) Specified pressure ranges can only be attained by means of changing the spring and/or internals. Pressure ratio Max. pressure ratio = P upstream: P downstream = 40 : 1 Min. pressure ratio = P upstream: P downstream = 1.1: 1 Flanges rated DIN (*) (*) the applied pressure rating depends on the process data. Component Material EN and/or (DIN) W.nr. Wetted parts Stainless steel X6CrNiMoTi Other parts Stainless steel X5CrNi O-rings FPM (Viton) Flanges PN igh pressure fig Vapour, gases and liquids DN Max. 200 C Max. 16 to 100 bar Max. pressure ratio 40: 1 Wetted parts : Special variants For lower downstream pressure range For higher upstream pressures With ASME rated flanges With other O-ring materials Accessories Pressure gauge with bottom connection (e.g. fig. 334) Cast iron elbow " BSP female thread/male thread (e.g. fig. 841) Install in a horizontal pipe, with spring cap on top Capacity See capacity chart in the introduction of this section Ordering code DN [mm] 1536 DN 10 - DN 100 When ordering, specify the following data: - upstream pressure - required downstream pressure ~16 Fig. DN 1 Weight Kvs-value [mm] [kg] [m3/hour] DN Pressure reducing valves and safety valves FA page 523