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Hardening method of metal hard sealed ball valve balls and valve seats

  At present, the commonly used hardening processes for the surface of  metal hard sealed ball valves  mainly include the following: (1) Surface welding (or spray welding) of hard alloy on the sphere can achieve a hardness of over 40HRC. The process of surface welding of hard alloy on the sphere is complex, with low production efficiency, and large area welding can easily cause deformation of the parts. Currently, there is relatively little use of surface hardening technology on the sphere. (2) The surface of the sphere is plated with hard chromium, with a hardness of 60-65HRC and a thickness of 0.07-0.10ram. The chromium plating layer has high hardness, wear resistance, corrosion resistance, and can maintain surface brightness for a long time. The process is relatively simple and the cost is relatively low. However, the hardness of the hard chromium coating will rapidly decrease as the temperature increases due to the release of internal stress, and its working temperature cannot exce
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Misunderstood check valve

  Check valves   may be the most easily misunderstood valve in history. If you mention check valves to most factory personnel, the typical reaction is "they don't work.". In fact, these personnel are likely to have removed internal components or refurbished the system to avoid using check valves. In other words, these valves may be the least popular valves currently in use. This article will explore the basic knowledge of check valves, how they work, what types they are, how to select and install them, how to solve their problems, and why they are not always problems. Simply put, check valves allow one-way flow and automatically prevent backflow (backflow) when the fluid in the pipeline is reversed. They are one of the few automatic valves that do not require auxiliary opening and closing. Although some valves can be equipped with external counterweights and damping devices in special circumstances, most valves do not have open/close control or external assistance from ot
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Does the shut-off valve have directionality? Why install in the direction?

  Globe valve , also known as shut-off valve, belongs to the forced sealing type valve and is a type of shut-off valve. There are three types of connection methods: flange connection, threaded connection, and welded connection. The "Three Modernizations" of valves in our country once stipulated that the flow direction of globe valves should be from top to bottom, so there is directionality during installation. The globe valve is designed with low inlet and high outlet to reduce flow resistance and save effort when opening the valve. When the valve is closed at the same time, the gasket between the valve shell and valve cover, as well as the packing around the valve stem, are not subjected to force and will not be affected by medium pressure and temperature for a long time. This can prolong the service life and reduce the probability of leakage. In addition, this can also replace or add packing when the valve is closed, making maintenance easier. In general, globe valves are l
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Introduction to the Function, Principle, and Characteristics of Globe Valves

  Globe valves   are used to cut off the flow of media, and are suitable for situations that require frequent opening. The sealing parts of a globe valve are the valve disc and valve seat. In order to ensure a tight closing of the globe valve, the mating surface of the valve disc and valve seat should be ground or a gasket should be used. The sealing surface can also be embedded with corrosion-resistant and wear-resistant materials such as bronze and stainless steel.The valve disc and valve stem of the globe valve are connected in a movable manner to ensure a tight fit between the valve disc and valve stem. The lifting and lowering of the valve disc of a globe valve is generally controlled by the valve stem. The upper part of the valve stem is a handwheel, and the middle part is a threaded and packing sealing section. The function of the packing is to prevent the internal medium of the valve body from leaking along the valve stem. The function of a shut-off valve 1、 The main function o
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Applicable occasions for check valves

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  The purpose of using a   check valve   is to prevent reverse flow of the medium, and a check valve is generally installed at the outlet of the pump. In addition, a check valve should also be installed at the outlet of the compressor. In short, in order to prevent reverse flow of the medium, check valves should be installed on equipment, devices, or pipelines. Generally, vertical lift check valves are used on horizontal pipelines with a nominal diameter of 50mm. The straight lift check valve can be installed on both horizontal and vertical pipelines. The bottom valve is generally only installed on the vertical pipeline at the pump inlet, and the medium flows from bottom to top. The swing check valve can be made with a high working pressure, with a PN of up to 42MPa, and a DN of up to 2000mm. According to the different materials of the shell and sealing components, it can be suitable for any working medium and any working temperature range. The medium is water, steam, gas, corrosive me
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Function of shut-off valve - Chinaxuval.com

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  A   globe valve   is a type of valve with a simple structure, small volume, light weight, low material consumption, and multiple optional properties. ​ The reasons why it is widely accepted and applied are as follows: Function of shut-off valve 1. It is mainly used for cutting off and throttling in pipeline systems or production equipment. Due to the lower friction between the sealing surfaces of this type of valve compared to gate valves, it is suitable for pipelines or devices with large pressure fluctuations and drastic temperature and pressure changes (such as the connection of nitrogen flushing pipelines). 2. The shut-off valve belongs to the forced sealing type valve, so the handle must be forcefully pushed to the fully closed position when opening and closing. When the medium flows from bottom to top, the fluid is filtered by the through check valve and enters the inner chamber of the through stop valve When the liquid medium flows through the through check valve from bottom t
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WHAT IS A HIGH PERFORMANCE OR DOUBLE OFFSET BUTTERFLY VALVE?

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  High Performance Butterfly Valves  use a disc offset from the seat center, hence the name Double Offset. In this configuration, the disc is eccentric, or offset, from the valve seat. As the disc starts to rotate, it moves away from the seat instead of across it. This design actually uses the line pressure to help give it its seal. This feature allows the use of offset butterfly valves in high‐pressure applications such as ethanol or HVAC. It generally uses PTFE or plastic as its seat material, but metal seats are also available to meet fire‐testing specifications like API 607. Offset Disc Butterfly Valves are comprised of the following components: Body Retainer Plate Seat Disc Stem Stem Seals Standard double offset butterfly valves come with a polymer seat, usually PTFE, with a metal backup for fire safety. Metal‐to‐metal seats are also available and may provide a higher sealing quality, and allow slightly higher temperatures. FEIDA VALVE is the top ranking  China double offset butte
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