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How to extend the service life of stainless steel metal seated butterfly valve

In general, we are most worried about the problem of stainless steel metal seated butterfly valves is rust. This is the common concern of the majority of users for metal products. In fact, stainless steel material itself is not easy to rust, but stainless steel materials are also divided into five categories, such as ferritic stainless steel, martensitic stainless steel, austenitic stainless steel, austenitic-ferritic stainless steel and precipitated carbide stainless steel. The

D673H-16C-stainless steel pneumatic triple eccentric butterfly valve

D673H-16C-stainless steel pneumatic triple eccentric butterfly valve

austenitic stainless steel has good corrosion resistance after normal heat treatment and will not rust easily. If the stainless steel butterfly valve rusts in normal use, it is mostly due to the precipitation of carbides along the grain boundary in the material to form a chromium-depleted zone, which causes the stainless steel hard-seal butterfly valve to rust.
Let’s take a look at what specific maintenance methods we should maintain during use in order to effectively avoid corrosion of the stainless steel metal seated butterfly valve and prolong its service life:
1. The stainless steel metal seated butterfly valve should be cleaned frequently during use, and the transmission device should be maintained and lubricated. Frequently troubleshoot faults in order to find faults and clear them in time.
2. The packing should be evenly packed and the cover should be tightened to prevent the medium from leaking from the packing for a long time and rust.
3. Pay attention to the connection method and direction of the valve to prevent leakage and erosion caused by misalignment.
4. The stainless steel metal seated butterfly valve is only used for adjustment, not fully open or fully closed, because the structural characteristics of the butterfly valve are not suitable for truncation, which will cause accelerated wear of the sealing surface.
5. Valves that have not been put into use for a long time should also be checked regularly to clean up dirt in time. Both ends of the butterfly valve channel should be closed to prevent long-term air oxidation. The product should be placed in a ventilated and dry place, not stacked or stored in the open air.
6. Eliminate the dirt on the valve parts before installation, carefully check the pressure of the valve mark to see if the diameter meets the requirements for use, and eliminate the defects caused by the transportation process.
7. The product switch must use the equipped hand wheel or electric or pneumatic device. Do not use external tools to cause damage to the valve. The handwheel butterfly valve is turned clockwise to close, otherwise it is open.
For stainless steel metal seated butterfly valves to be used for a long time, it is important from product selection to post-maintenance. Choosing a trustworthy brand is the first step, and maintenance is the continuation of quality. Of course, good manufacturers will also have more guarantees after sales. If users do not understand maintenance or have any questions or questions, they can directly contact the manufacturer for professional assistance. Tanghai Valve solemnly promises to pay two for each failure within two years. Is your trustworthy butterfly valve manufacturer.

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:
The difference and application of stainless steel 430, 304, 316
Ways to Extend the Service Life of Valves
Features and application area of double eccentric butterfly valve
Valve actuator / actuation -(5)- advantages

What are the characteristics of the hard seal butterfly valve

Hard seal butterfly valve is a kind of butterfly valve with eccentric metal seal structure, and it is usually required to be installed horizontally in the pipeline. The sealing form of the metal hard seal butterfly valve is usually a metal-to-metal seal, and the sealing pair is composed of a metal hard material to a metal hard material. Hard-sealed butterfly valves can be driven by turbine manual, electric, pneumatic and so on.

triple offset butterfly valve-double flange- (5)

triple offset butterfly valve-double flange- (5)

Nowadays, hard-sealed butterfly valves have been widely used in many fields such as petroleum, chemical industry, metallurgy, power generation, etc., to cut off or control the circulating medium in the pipeline system. At this stage, there is a relatively advanced hard-sealed butterfly valve, which is a triple-eccentric metal seated butterfly valve. Its body and seat are a conjoined component. On the sealing surface layer of the valve seat, a temperature-resistant and corrosion-resistant alloy material is surfacing welded. , And fix the multi-layer soft stacked sealing ring on the valve plate. The novel design allows the triple eccentric butterfly valve to overcome the shortcomings of poor sealing performance. The advantages of the triple eccentric butterfly valve are high temperature resistance, low friction when opening and closing, and when closed, the butterfly plate compensates for the seal along with the increase of the torque of the transmission mechanism, which greatly improves the sealing performance of the hard seal butterfly valve and prolongs the service life of the valve.

The advantages of the triple eccentric hard seal butterfly valve are:
1. The unique three-eccentric design enables frictionless transmission between the butterfly plate and the sealing surface of the valve body, reducing wear and extending the service life.
2. It can adapt well to low temperature, normal temperature and high temperature environment.
3. Pneumatic and electric devices can be configured according to the needs of users to meet the needs of remote control and program control.

The shortcomings of the triple eccentric hard seal butterfly valve are:
1. The butterfly plate of the hard sealing butterfly valve is fixed by multiple layers of soft and hard stacked sealing rings. When the butterfly plate is in the normally open state, the flowing medium will flush the sealing surface positively, which will affect the sealing performance of the valve over time.
2. Because the overall structure of the hard-sealed butterfly valve’s butterfly plate is too thick and the flow resistance is relatively large, the valve is not suitable for diameters below DN200.

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:
pneumatic fluorine-lined butterfly valve vs pneumatic hard-sealed butterfly valve
Electric ball valve-metal seated vs soft-seated type
Fluorine-lined butterfly valve vs metal seated butterfly valve
The sealing characteristics and principle of eccentric butterfly valve

Hard seal installation method of ball valve

Hard seal installation method of ball valve:

1) Remove the protective covers on both sides of the flange, and rinse and clean with the valve fully opened.

ball valve (6)

ball valve (6)

2) Before installation, the whole machine should be tested according to the specified signal (electrical or pneumatic) (to prevent vibration caused by transportation from affecting the performance), and then it can be installed online (wiring according to the electric actuator circuit diagram).
3) Before preparing to connect with the pipeline, flush and remove the remaining impurities in the pipeline (these substances may damage the valve seat and ball).
4) During installation, please do not use the actuator part of the valve as a lifting point to avoid damage to the actuator and accessories.
5) This type of valve should be installed in the horizontal or vertical direction of the pipeline.
6) The pipeline near the installation point should not be drooping or bear external force. Pipe supports or supports can be used to eliminate pipeline deviation.
7) After connecting with the pipeline, please cross-tighten the flange connecting bolts with the specified torque.

Tianjin Tanghai Valve Manufacturing Co., Ltd. is one of the largest ball valve manufacturers in China, main products are butterfly valves, check valves, gate valve and globe valves. Key words:  butterfly valve, lug type butterfly valve, wafer type butterfly valve, U-type butterfly valve, double flange butterfly valve, gate valves, check valves, globe valves, valve parts (Valve body, Valve disc, Valve shaft, Valve seat…)