Selection of manual butterfly valves

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This post was last edited by Sammy_Wang on 2015-6-15 at 11:35. Imported brands are required, such as Gemmi, KSB, or Ebro. I was wondering if any dealers could help identify the specific models; please contact me via private message. Thank you. 1. Valve List
Valve Description | DN | PN | Quantity (pieces) | Valve Type | Connection Method | Actuation Method
--- | --- | --- | --- | --- | --- | ---
Imported manual valve 200 | 163 | Butterfly valve | Flanged | Manual
Imported manual valve 150 | 1 | Butterfly valve | Flanged | Manual
Imported manual valve 80 | 161 | Butterfly valve | Flanged | Manual
Imported manual valve 50 | 164 | Butterfly valve | Flanged | Manual
Domestic manual valve 25 | 162 | Butterfly valve | Welded | Manual

2. Technical Requirements
2.1 General Provisions
2.1.1 The design, production, and installation of valves shall comply with this technical annex, the latest valid Chinese specifications and standards, as well as equivalent international standards, and shall be submitted to the tendering party for approval. If the requirements specified in this technical annex are stricter than the approved standards, the requirements of this technical annex shall be followed. 2.1.2 The valves provided by the bidder shall ensure 100% operational reliability, which is reflected in the flexibility of the valves’ operation, the suitability of the valve materials for the applicable media, and the service life of the valve components. Valves with identical functions and operating conditions should be interchangeable, and the specifications of the valves will be standardized as much as possible. 2.1.3 The valves shall be delivered in their fully assembled state after installation and testing prior to leaving the factory, so that they can be installed on-site directly without the need for pre-assembly. 2.1.4 All valve designs and selections shall be suitable for the characteristics of the limestone slurry medium and the operating conditions. The valves in the slurry system must take into account the wear and corrosion caused by the medium, with special attention paid to the characteristics of flue gas desulfurization projects in power plants. Data sheet for limestone slurry medium
Medium: Limestone slurry
Physical properties Unit Maximum value Design value Minimum value
Density, kg/m3 1290 1268 1148
Temperature, °C 50
pH 1) 9.0 8.5 7.0
Viscosity, mPa·s
Solid content, wt.% 30
Components 3) Solids: 0.52
Gypsum, wt.% 0
Calcium sulfite, wt.% 26.81
CaCO3, wt.% 1.23
MgCO3, wt.% 0
CaF2, wt.% 0
MgF2, wt.% 0
Ash content, wt.% 0
Inert substances, wt.% 1.43
Cl-, 2) ppm 100 24
1) During startup, the pH value may be as low as 4.5. 2) Pumps and pipes are effective for a CL- concentration of 20,000 ppm. 3) The minimum value/maximum value correspond to the minimum/maximum operating conditions, respectively. 2.1.5 During the contract period, the bidder shall establish and maintain a quality system that meets the requirements of the ISO 9000-2000 quality system standard and is appropriate for its scope of supply. 2.1.6 The materials used must be suitable for the incoming medium and the working environment. Especially for the valve seat surface, materials resistant to wear and fluid erosion must be used. Under various operating conditions, the design life of each control valve is not less than 200,000 hours. Under any conditions, the valve housing and valve disc will not experience significant wear or functional defects before 10,000 hours of operation. 2.1.7 For the main valves in systems whose working medium is limestone slurry or gypsum slurry, butterfly valves should be used; their valve discs shall be made of corrosion-resistant and wear-resistant alloy materials, with a quality level at least equivalent to or superior to 1.4529. 2.1.8 All valves shall meet the following requirements: (1) For valves installed outdoors, their electric actuators shall be suitable for use in outdoor environments. (2) Gray cast iron is not allowed to be used for any valves. (3) For valves operating under vacuum conditions, parallel dual-seal vacuum diaphragm valves are preferred, rather than water seal valves. (4) The valves in the slurry system must take into account wear and corrosion caused by the medium, and the valve material should be selected based on the most severe operating conditions. The slurry valves shall be of the straight-through type, with their valve discs and valve stems made of alloy steel that is resistant to corrosion and wear (valve discs with rubber lining or surfaces coated/plated with alloys are not acceptable); the material must contain at least 13% chromium. The specific materials for each component of the valve shall be filled in by the bidder. Materials and service life of the main components of butterfly valves (the bidder may adjust the component names according to the actual structure of the valve) Serial Number Component Name Material Weight Service Life (hours) Remarks 1 Valve body 2 Valve seat 3 Valve disc 4 Valve stem 5 Valve stem bolts and nuts 6 Handle 7 Worm gear 2.2 Design and manufacturing requirements 2.2.1 All butterfly valves shall be of the midline-type rubber-lined design. The area between the butterfly plate and the valve body is sealed with a fully synthetic rubber lining; when closed, the butterfly plate and the rubber lining provide good sealing performance, with the required sealing standard being ANSI B16.34 double bubble class VI. At a closing angle of ±4 degrees (relative to a 0-degree closing angle of the butterfly valve), the valve maintains 100% zero leakage, with low friction between the butterfly valve disc and the seal (rubber lining). Under normal use, the synthetic rubber lining can withstand more than 50,000 opening and closing operations while maintaining excellent sealing performance, and the average service life of the valve should be around 30 years. To ensure quality, the rubber valve lining should be manufactured by the same brand supplier as the valve, and the lining material must be certified by the U.S. FDA. The tightness of the valve seat will be tested from two directions to achieve dual sealing. 2.2.2 The shaft of the butterfly valve is made of 304 stainless steel with 18% Cr or a higher-grade material; the shaft and the valve disc are connected without the use of pins or bolts, which ensures that the shaft remains completely dry and thus eliminates the possibility of electrochemical corrosion between the shaft and the valve disc. This ensures smooth and steady operation of the valve, extending its service life. The valve stem is required to have at least three seals, and the bearings are self-lubricating. To prevent the valve stem from deflecting, the valve should have a triple stem support mechanism to maintain its optimal position over the long term. 2.2.3 The valve is subjected to hydrostatic testing in accordance with the relevant ISO standards; in addition, a seat tightness test is carried out at the rated pressure, whereby the test pressure for the valve body is 1.5 times the nominal pressure, and the test pressure for the seat is 1.1 times the nominal pressure. 2.2.4 All valves are fully sealed under a front-to-back pressure difference equal to the operating pressure. 2.2.5 For handwheels with a diameter in the range of 400 mm, the maximum allowable starting force is 300 N ； For handwheels with a larger diameter, it is 600N. 2.2.6 Electric devices shall be suitable for their respective operating environments. Outside, the ambient temperature is 60℃ ； Indoors, the ambient temperature can reach 45°C. The motor coils will have moisture-proof measures. The insulation class is F. 2.2.7 The design ensures that the valve disc and rubber sleeve of the butterfly valve are the only components in contact with the fluid, while all other parts remain completely dry. Corrosive materials are not used. Places where water tends to accumulate will be provided with drainage holes. 2.2.8 Plastic or bakelite valve handwheels are used only on diaphragm valves. 2.2.9 The valve plates and valve stems of all slurry pipelines shall be made as a single unit, and must be compatible with the pipeline material as well as the requirements regarding operating pressure and temperature. 2.2.10 Piping valves in contact with limestone slurry/gypsum slurry shall be suitable for pickling (using acids that do not damage EPDM). 2.2.11 The 48 electric butterfly valves used for the demister flushing water are equipped with metal sealing elements; there must be a difference in hardness between the valve seat and the seal, with the seal having a higher hardness value. 2.2.12 The nominal diameter, nominal pressure, and an arrow indicating the flow direction must be marked on each valve body. It is also equipped with a KKS coding sign made of corrosion-resistant metal plate. 2.2.13 Unless otherwise required by the valve’s function, the internal cross-section of the valve body shall be consistent with the nominal diameter of the connecting pipe. 3. Delivery schedule: The delivery schedule for the equipment must meet the requirements of the project installation timeline; all equipment shall be delivered by June 10, 2015.