DN65~DN80 Socket Welded Advanced Technology Blow-Down Valve Series for Enhanced System Efficiency

• Customization: Available
• Media: Gas
• Temperature: High Temperature
• Model NO.: Series Blow-down Valve
• Actuator: Electric
• Material: Carbon Steel
• Structure: Through Way Globe Valve
• Sealing Form: Gland Packings Globe Valve
• Stem Thread Position: Outside Screw Stem Globe Valve
• Standard: DIN, GB, ANSI, JIS
• Type: Through Way Type/Angle Type/Series Type and Y Type
• Specifications: DN20/DN25/DN40/DN50/DN65/DN80
• Nominal Pressure: ANSI150-ANSI2500
• Rated Stroke: 25405060 mm
• Fluid Temperature: -20ºC~566ºC
• Connection Type: Sw, Bw, Flanged
• Flow Control: Continuous Flow Control Conditions
• Flow Control Way: Continuous Flow Control Conditions
• Leakage Class: 0 Leakage (API598)
• Materials: Carbon Steel/Alloy Steel/Stainless Steel
• Forging Mode: Standard Connection: Sw/Optional Connection: Bw or
• Casting Mode 1: ANSI900 and Below Use Flange Connections
• Casting Mode 2: ANSI1500 and Above Are Butt Welded Connections
• Casting Mode 3: Cap of Angle and Straight Through Body: Bolted
• Transport Package: Wooden
• Trademark: SNT
• Origin: China
• HS Code: 8481804090
• Production Capacity: 500000PCS/Year

Product Description

 

Standard Mat.Comparison

 

 

 

^No.	^Part name	^Standard material		^No.	^Part name	^Standard material
		^<ANSI 900	^>=ANS|1500			^<ANSI900	^>=ANSI 1500
^1	^Valve body	^A105N	^A105N	^83	^Screw holder	^HBsc2	^HBsc2
^2	^Top cover	^A105N	^A105N	^85	^Flat head round key	^Carbon steel	^Carbon steel
^3	^Body screw	^A193-B7 Colored zinc plating	^A193-B7 Colored zinc plating	^86	^Lock nut	^Carbon steel + galvanized	^Carbon steel + galvanized
^4	^Body nut	^A194-2H Colored zinc plating	^A194-2H Color zinc plating	^87	^Hex socket screws	^304SS	^304SS
^5	^Valve core	^A276410+HF	^316+S503+S505	^88	^Nameplate	^304SS	^304SS
^6	^Valve seat	^A276410+HF	^316+ZY08	^89	^Connecting flange	^Carbon steel	^Carbon steel
^8	^Wrap shims	^304+GRAPHITE	^304+GRAPHITE	^90	^Limit anti-turn block	^Carbon steel + galvanized	^Carbon steel + galvanized
^9	^Sleeve	^440C+HF	^316+S101	^91	^Nuts	^Carbon steel + galvanized	^Carbon steel + galvanized
^14	^Wrap shims	^304+GRAPHITE	^304+GRAPHITE	^92	^Thrust needle roller bearings	^Bearing steel (standard material	^Bearing steel (standard material
^17	^Packing plate	^A351 CF8	^A351 CF8	^93	^Hex set screws	^304SS	^304SS
^23	^Nuts	^A194-2H	^A194-2H	^252	^Packing gland	^A276410	^A276410
^24	^Screw	^A193-B7	^A193-B7	^255	^Packing assembly	^Flexible graphite	^Flexible graphite
^80	^Support stand pole	^Carbon steel + galvanized	^Carbon steel + galvanized	^257	^Packing pad	^A276410	^A276410
^81	^Hex head bolts	^304SS	^304SS	^572	^Handwheel	^Carbon steel	^Carbon steel

 

About SNT Blow-down Valves

SNT Machinery(Qingdao) Co., Ltd. (referred to as SNT) is a valve manufacturing company that specialized in the development, design and production of fluid flow and valve technology.

SNT drain valve can be widely used in continuous throttling control, such as: boiler continuous drain, high pressure vessel and reactor sampling, high pressure discharge, boiler feed pump bypass system release device, high pressure difference (pressure release) conditions, heater drain to the condenser process due to corrosion and high flow rate flash conditions. Compared with the traditional valve, the SNT valve is more robust and durable, which is suitable for continuous drain conditions that can cause serious damage to the valve. Because in the continuous drain working condition, the flow rate is high, the erosion is more serious, the traditional cutoff drain valve is fragile, even the venturi valve is also fragile.

The SNT drain valve breaks the traditional internal structure design concept. The flow channel between the valve core and the cylindrical valve seat adopts smooth design, which can accelerate the fluid flow until the fluid reaches the downstream of the valve seat, and the chamber suddenly becomes larger. At this time, the pressure drop caused by the center part of the flow channel leads to the rapid expansion of the fluid toward the flow center part. While the energy of the fluid flow also quickly disperses and evaporates, and the fluid enters turbulent condition. The efficient discharge process ensures that the fluid can form steam when supersaturated, while cooling the remaining liquid, which is a typical way to use flash evaporation in liquid flow.

In order to meet the various needs of the device, we can produce valves in the pressure range of ANSI 150 to ANSI 2500. Standard stop valve size is 3/4"(DN20), 1"(DN25), 1.1/2"(DN40), 2"(DN50), 2-1/2"(DN65) and 3"(DN80). The standard form of SNT valve is angular connection, to allow a uniform flow of fluid.The through way type stop valves are also available. According to the control, it can be divided into manual, pneumatic and electric control. For accurate throttling control, based on the flow evaluation in the SNT internal-design structure, the Fluent-Code of a computational Fluid Dynamics is used to simulate and analyze the flow channel and its pressure drop. All SNT internals are usually surface-hardened with high-quality Co-Ni based alloys or surface-treated with Cr-N ceramic coatings to prevent abrasion and corrosion due to high pressure drops and flow rates.


 
 

 

Product Description

SNT - SERIES DRAIN VALVE
3/4"(DN20)~3"(DN80)ANSI Class 150~1500
 

^Applications		^-Steam boiler, evaporator and other boiler water continuous drain control-Flow and pressure regulation and flash application-Steam boiler, evaporator and other boiler water intermittent drain control		^Manual operation control
^Nominal pressure		^ANSI 150, 300, 600, 900, 1500		^Pressure class >=ANSI1500 for RT test
^Nominal diameter	^Forging mode	^3/4 "(DN20), 1"(DN25) and 1.1/2 "(DN40), 2"(DN50)		^ANSI 150, 300, 600, 900, 1500
	^Casting mode	^2.1/2"(DN65), 3"(DN80)		^ANSI 150,300, 600, 900, 1500
^Connection mode	^Forging mode	^-Standard connection: SW-Optional connection: BW or flanged
	^Casting mode	^-ANSI 900 and below with flange connections-ANSI1500 and above are butt welded- Cap of Angle body: bolted connection		^Metal self-sealing structure form for option
^Design calculation		^-Angular connection- Under the condition of high pressure difference, two or more Angle valves are used for fluid pressure precise control-The size of the seat hole is calculated by strict design-Verified by CFD analysis and testing- Compound hole plate can be configured for actual high pressure difference conditions- Suitable for forging, casting, bar stock- Heat treatment of valve internalsValve core: surface hardening or nit riding treatmentSeat: Nit riding or surfacing with STL alloy		^Other hole types: Conical hole/labyrinth runnerSurface hardening: surfacing STELLITE Gr.6Surface hardening of seat: Other options
^Material		^-Carbon steel- Alloy steel- Stainless steel High quality Alloy steel	^A105N, A182-F22A182-F304(L),A182-F316(L)As required by customer

 

^{Notes:
1.S101 hard surface technical description: HRC≥55, metallurgical combination, not easy to fall out;
2.S503 hard surface technical description: thickness 1.5mm, hardness HRC≥55, binding force 400MPa, not easy to fall out;
3.S505 hard surface technical description: thickness 0.3mm, hardness HRC≥65, binding force ≥250MPa;}



Rated flow coefficient comparison table



Application of Typical Working Conditions
 

^{As shown in the figure on the left, according to ASME B31.1 Power Boilers and Piping, intermittent drain valves are usually used in Zone 2 and are installed directly in boiler or boiler piping. There are also continuous drain valves, traps, and safety valves, etc.}
 

<sup>According to §122.1.4 of ASME B31.1 Power Boilers and Piping, the piping is usually fitted with 2 valves in series, a Y-type intermittent drain valve and an emergency stop valve.

The intermittent drain valve usually adopts the lever type rapid discharge mechanism, which can realize the rapid opening and closing. When the valve is opened, the sediment, dirt and other particles at the bottom of the boiler can be discharged quickly, no more than 3S. If the time is too long, a large amount of boiler water will be discharged, resulting in a great waste of resources. The flow channel is close to the straight pipeline.

The emergency stop valve is used to realize the strict cut-off of the pipeline and prevent the waste of resources when the previous intermittent drain valve fails.</sup>
 

Conditions&Solutions

 

Pressure and Temprature Parameters

 

SNT Valve Advantages

 

^{1. SNT is the set design, development, production, sale and service of industry and trade-oriented enterprises.}

^{2. Good quality, price and service by professional workers with creative solutions to problems.
3. Manufacture for Special Equipment Type Test Certificates.}

^{4. According to the requirements in ISO9001 and API SPECQ, our company determines and preparencessary control methods, processes and equipment(including inspection and testing equipment), as well as process equipment, so as the ensure the compatibility of design, manufacturing, inspection, test, installation and service with the whole system and their completeness.}

<sup>5. Excellent research and development team. Nearly 100 patents for products.
6. SNT is one enterprise specializing in integrated solutions for Control valves and associated actuators in Petroleum, chemical, Power, Storage Tank, Air Separation, Coal Chemical, Liquefied Natural Gas Industry etc.</sup>

 

Production application

 

 

 

Company Profile