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Properties of triple eccentric butterfly valve

Performance advantages of triple eccentric butterfly valve:
1. It integrates adjustment and cut-off, and has strong controllability.
The design of the new triple eccentric butterfly valve adopts a double safety structure. In order to prevent the deformation of the disc, the dislocation of the valve stem, and the occlusion of the sealing surface caused by the

D943H-16C-metal seated stainless steel electric triple offset butterfly valve

D943H-16C-metal seated stainless steel electric triple offset butterfly valve

influence of fluid pressure and temperature, two independent stoppers are installed on the upper and lower sides of the disc. The push ring ensures the normal operation of the valve under any working conditions; in order to prevent the valve stem from being damaged and flying out and causing unexpected accidents, independent valve stem flying-out prevention mechanisms are designed at the lower end of the valve inside and outside.
2. No dead zone design, small opening torque.
The shape of the valve plate of the triple eccentric butterfly valve is an elliptical cone, and its surface is surfacing with hard alloy, which has excellent wear resistance. The floating U-shaped stainless steel valve seat has the function of automatically adjusting the center. When the valve is opened, the valve plate of the elliptical cone sealing surface is first separated from the U-shaped elastic valve seat, and then rotated; when the valve is closed, the valve plate rotates, and the valve plate automatically adjusts the center to the elastic valve seat under the action of the eccentric shaft. Seat pressure deforms the seat until the seat is in close contact with the oval conical sealing surface of the valve plate. When the valve is switched on and off, the disc does not scratch the valve seat, the torque of the valve stem is directly transmitted to the sealing surface through the disc, and the opening torque is small, thus eliminating the common jumping phenomenon when opening the valve, that is, eradicating the dead zone (no sense band) . This design without dead zone enables the triple eccentric butterfly valve to enter the controllable area almost from 0 opening to 90 opening, and its control ratio can be as high as 1001 or more, which is twice that of ordinary butterfly valves.
3. Zero leakage, high temperature and high pressure resistance.
The biggest feature of triple eccentricity is that it fundamentally changes the sealing structure. It is no longer a position seal, but a torsion seal, that is, it does not rely on the elastic deformation of the valve seat, but completely relies on the contact surface pressure of the valve seat to achieve the sealing effect. This sealing structure enables the triple eccentric butterfly valve to achieve a hard seal of level VI and achieve true zero leakage. At the same time, due to the selection of the metal valve seat and the structural characteristics of the face seal, the problem of high temperature and high pressure resistance is also easily solved. In addition, the triple eccentric butterfly valve adopts the body seat structure, which makes the valve structure more compact, and reduces the chance of the valve seat directly contacting the medium, reduces the degree of erosion of the valve seat, and can effectively prevent small solids in the medium. The impact of the material and thermal expansion may cause the sealing surface to bite, thereby extending the service life of the valve seat. The new triple eccentric butterfly valve can not only replace the body seat, but also the disc sealing surface and disc are independent, and the disc sealing surface can also be replaced, which greatly reduces the maintenance cost.

TH Valve is a professional manufacturer of butterfly valvegate valvecheck valveglobe valveknife gate valve, ball valve with API, JIS, DIN standard, used in Oil, Gas, Marine industry, Water supply and drainage, fire fighting, shipbuilding, water treatment and other systems, with Nominal Diameter of DN50 to DN1200, NBR/EPDM/VITON, Certificates & Approvals: DNV-GL, Lloyds, DNV, BV, API, ABS, CCS. Standards: EN 593, API609, API6D

Video of triple eccentric butterfly valve:

Related news/knowledge:

Application of double eccentric butterfly valve and triple eccentric butterfly valve
Precautions for the use of triple eccentric metal seated butterfly valve
What is a triple eccentric metal seated butterfly valve
Advantages and Disadvantages of Triple Eccentric Butterfly Valves

Valve material and valve standards-(7)- Monel alloy

Monel alloy for corrosion resistant valve
1. Introduction/overview of Monel alloy:
Monel alloy, cast nickel alloy, Hastelloy alloy, etc. are all materials for making special purpose valves. Monel alloy is a Ni-Cu alloy in nickel-based corrosion-resistant alloys. It was first developed by the US Nickel Company. Its typical composition is 70% Ni and 30% Cu. It is the most widely used nickel-based corrosion-resistant alloy.

Monel alloy not only has high strength and toughness, but also has excellent resistance to corrosion by reducing acid and strong alkali media and sea water, so it is usually used to manufacture and transport hydrofluoric acid (HF), salt water, neutral media, and alkali salts. And reducing acid medium equipment. Monel alloy is also suitable for dry chlorine, hydrogen chloride, high temperature chlorine (425°C) and high temperature hydrogen chloride and other media, but it is not resistant to corrosion by sulfur-containing media and oxidizing media (such as nitric acid, media with high oxygen content), and it is nickel It reacts violently with sulfur and oxygen and easily forms Ni3S2 and NiO.

2. Performance of Monel alloy:
Monel alloy is a Ni-Cu solid solution, where Cu is used as a non-oxidizing resist added to Ni, which improves the corrosion resistance of nickel alloys and acts as a strengthening alloy. The addition of C can improve the casting performance of the alloy, but only 0.15% of C can be dissolved in the alloy at room temperature, and the excess C will be precipitated as a graphite phase. Adding 1.5%-3.5% Fe can also improve the casting performance of the alloy. Adding Mn and Si can improve the mechanical properties of the alloy, especially the content of Si has an important influence on the mechanical and physical properties of the Monel alloy.

3. Classification of Monel alloy:
Monel alloys are classified into casting alloys and deformed alloys.
3.1 Deformation alloy: There are more than 10 types of deformed Monel alloys in the United States, such as Monel400, MonelC, Monel403, Monel404, Monel R2405, Monel406, Monel411, MonelK500, MonelK501 and Monel502. Because Monel has its own representation methods in different American standard systems, SAE and ASTM jointly developed ASTM2SAE unified digital system (unified numbt system2 UNS) in order to facilitate the use and unified management of calculations. In the United States’ UNS, nickel alloys have 5 grades of deformed Monel alloys, including solid solution hardened No5500 (Monel400), No4404 (Monel404) and No4405 (MonelR2405), and precipitation hardened NO5500 (MonelK500) and NO5502 (Monel502). ) Etc. (refer to Table 1). Among them, the deformed Monel alloy commonly used in the manufacture of corrosion-resistant valves is Monel400 and MonelK500.
Table 1. Chemical composition of deformed Monel alloy in United States UNS

Grade name chemical composition/ %
C Si Mn S Ni Fe others
NO4400(Monel400) ≤0.3 ≤0.5 2 ≤0.024 63-70 ≤2.5 Cu base
No4404(Monel404) ≤0.15 ≤0.1 ≤0.1 ≤0.024 52-57 ≤0.5 Cu base, Al≤0.05
No4405(MonelR2405) ≤0.3 ≤0.5 ≤2.0 0.025-0.06 63-70 ≤2.5 Cu base
No5500(MonelK500) ≤0.25 ≤0.5 ≤1.5 ≤0.01 63-70 ≤2 Cu base, Al213-3115,Ti0135-0185
NO5502(Monel502) ≤0.10 ≤0.5 ≤1.5 ≤0.01 63-70 ≤2 Cu base, Al215-315

3.2 Casting alloy: The American cast Monel alloy has five grades of M35-1, M35-2, M-30H, M-25S and M-30C in ASTM A494 (Table 2), which is in the US Federal Standard QQ-N2-88 There are also 5 cast Monel alloys (Table 3).
Table 2. Cast Monel alloy in ASTM A494:

grade name chemical composition /% mechanical properties
C Mn Si P.S Cu Fe Ni Nb Compressive strength/Mpa Tensile strength/Mpa Elongation rate/% HB
M35-1(a) ≤0.35 ≤1.5 ≤1.25 ≤0.03 26-33 ≤3.5 Ba ≥450 ≥170 ≥25
M35-2 ≤0.35 ≤1.5 ≤2.00 ≤0.03 26-33 ≤3.5 Ba ≥450 ≥205 ≥25
M-30H ≤0.30 ≤1.5 2.7-3.7 ≤0.03 27-33 ≤3.5 Ba ≥690 ≥415 ≥10
M-25S ≤0.25 ≤1.5 3.5-4.5 ≤0.03 27-33 ≤3.5 Ba 243-294(b)
M-30C(a) ≤0.30 ≤1.5 1.0-2.0 ≤0.03 26-33 ≤3.5 Ba 1-3 ≥450 ≥225 ≥25 125-130(b)

Notes:
1.Ba=balance, means the balance is all Ni content.
2. To remove the weldability, it should be M3521 or M230C
3. This table is a data parameter
4. HB minimum is 300
Table 3 QQ2N2288 cast Monel alloy:

QQ-N-288 chemical composition /% mechanical properties
C Si Mn Cu Fe Ni Nb Compressive strength/Mpa Tensile strength/Mpa Elongation rate/% HB
A ≤0.35 ≤2.0 ≤1.5 26-33 ≤2.5 62-68 ≥448 ≥224 ≥25 125-150
B ≤0.30 2.7-3.7 ≤1.5 27-33 ≤2.5 61-68 ≥689 ≥455 ≥10 240-290
C ≤0.20 3.3-4.5 ≤1.5 27-31 ≤2.5 ≥60 ≥825 ≥550 ≥10 250-300
D ≤0.25 3.5-4.5 ≤1.5 27-31 ≤2.5 ≥60 ≥300
E ≤0.30 1.0-2.0 ≤1.5 26-33 ≤2.5 ≥60 1-3 ≥448 ≥221 ≥25 125-150

TH Valve is a professional manufacturer of butterfly valvegate valvecheck valveglobe valveknife gate valve, ball valve with API, JIS, DIN standard, used in Oil, Gas, Marine industry, Water supply and drainage, fire fighting, shipbuilding, water treatment and other systems, with Nominal Diameter of DN50 to DN1200, NBR/EPDM/VITON, Certificates & Approvals: DNV-GL, Lloyds, DNV, BV, API, ABS, CCS. Standards: EN 593, API609, API6D.

Related news /knowledge:
Valve material and valve standards-(8)- Monel alloy application;
Detailed introduction of soft sealing butterfly valve-(2);
Code of valve sealing or lining material;
Classification and advantages of gate valve;