The card sleeve needle valve is a valve product used for precise flow control, and the valve disc is usually integrated with the valve stem. This article mainly introduces the aspects that need to be addressed for the anti-corrosion of sleeve needle valves.1. The valve body of the sleeve needle valve needs to be corrosion-resistant, so some anti-corrosion materials such as stainless steel, carbon steel, etc. need to be used. However, it is necessary to choose appropriately, as corrosion is a complex issue that is not an easy task. The difficulty in choosing valve body materials lies not only in corrosion issues, but also in considering high pressure and temperature resistance, as well as production costs, and so on.2. Under low pressure and temperature conditions, using non-metallic materials as valve body materials can often effectively prevent corrosion.3. Adopting lining measures, such as lining with lead, lining with aluminum, lining with engineering plastics, rubber, and various synthetic rubbers, etc., if the medium conditions permit, is actually a cost-effective method.4. The outer surface of the sleeve needle valve body is also subjected to atmospheric corrosion, and generally steel materials are protected by painting.

Stainless steel sleeve ball valves are easy to operate and maintain, suitable for general working media such as water, solvents, acids, and natural gas, and also suitable for media with harsh working conditions. Let's introduce the working principle of stainless steel sleeve ball valve below.Stainless steel sleeve ball valves are suitable for various pipelines with PN ranging from 1.0 to 12.5MPa and working temperatures of -29 to 180 ℃ (with reinforced polytetrafluoroethylene sealing ring) or -29 to 300 ℃ (with polystyrene sealing ring). Stainless steel sleeve ball valves are used to cut off or connect media in pipelines, and are made of stainless steel 201, 304, 316, etc. They can be used for various media such as water, steam, oil, nitric acid, acetic acid, etc.Stainless steel sleeve ball valve relies on rotating the valve core to make the valve unobstructed or blocked. Ball valve switches are lightweight, small in size, can be made into large diameters, reliable in sealing, simple in structure, easy to maintain, and the sealing surface and spherical surface are often in a closed state, which is not easily eroded by the medium. They are widely used in various industries.

The working principle of the card sleeve joint is to insert the steel pipe into the card sleeve, lock it with the card sleeve nut, resist the card sleeve, and cut into the pipe to seal it. It does not require welding when connected to steel pipes, which is beneficial for fire prevention, explosion prevention, and high-altitude operations, and can eliminate the disadvantages caused by welding and carelessness. Therefore, it is a good connector in the piping of automatic control devices for systems such as refining, chemical, petroleum, food, pharmaceuticals, and instrumentation. Suitable for connecting pipelines such as oil, gas, and water.Assembly method:The performance of sleeve type pipe joints is not only related to the material, manufacturing accuracy, heat treatment, etc. of the parts, but also to the assembly quality. Therefore, the assembly should be carried out according to the following methods.1: Cut the pipe according to the required length on a specialized machine tool, or manually saw it. The perpendicularity of the cut surface to the centerline of the pipe shall not exceed half of the tolerance of the pipe on the outside.2: Remove burrs, metal shavings, and dirt from the inner and outer circles of the pipe end.3: Remove rust proof oil and dirt from all parts of the pipe joints.4: Arrange the curtain in order, insert the card sleeve onto the pipe, and then insert the pipe into the bottom of the tapered hole in the joint body, forming a square card sleeve. While tightening the nut, rotate the pipe until it stops moving, and then tighten the nut 1-1 1/3 turns.

During the use of the card sleeve connector, leakage may occur, so we can take relevant measures to prevent such phenomena from happening. The leakage prevention measures are as follows:For sleeve joints, leakage is often caused by the loosening of the pneumatic ball valve sleeve or deformation of the pipe end face due to significant external or impact forces on the pipeline. At this time, it is necessary to check whether the sleeve is out of roundness, whether the cutting edge is damaged, whether the pipe end is intact, and the degree of compression of the sleeve nut. At the same time, external forces on the pipeline should also be removed. For expansion type pipe joints, leakage is often caused by excessive expansion, substandard quality, or repeated disassembly, resulting in deformation or cracking of the expansion. In this case, the front end can be cut off and re expanded.Re select the "о" ring with the same outer diameter and thicker cross-section, or cut or grind the sealing surface with a stop groove to reduce the depth of the stop groove and provide sufficient elastic deformation for the "о" ring. When there is a leakage at the pipe joint using oil resistant rubber plate, wool felt, soft steel cardboard, combined sealing gasket or sealant, regardless of the material, the sealing element of the sleeve joint should be checked for damage, deformation, aging and excessive roughness, and then corresponding measures should be taken.

There are many forms of card sleeve connectors, and the card sleeve is a metal ring with a sharp edge on one end of the inner circle. When connecting, first screw the joint body into the interface of the hydraulic component, then place the connecting pipe into the joint body and tighten it, and then use a nut to tighten the sleeve. During the compression process, the cutting edge of the sleeve cuts into the outer surface of the connecting pipe, forming a sealing surface. At the same time, the sleeve deforms and arches, coming into contact with the inner conical surface of the joint body to form a spherical sealing surface. Whether the cutting edge of the card sleeve can cut into the oil pipe is the key to connection and sealing, otherwise oil pipe pull-out accidents may occur during operation.Installation steps for card sleeve connectors:(1) According to the requirements, the pipes that need to be pickled should be pickled first;(2) Cut the pipe according to the required length using sawing machines or specialized pipe cutting machines, and it is absolutely not allowed to use melting (such as flame cutting) or grinding wheels for cutting; Remove burrs, metal chips, and dirt from the inner and outer circles of the pipe end; Remove rust inhibitors and dirt from pipe joints; At the same time, it is necessary to ensure the roundness of the pipe;(3) Insert the nut and sleeve into the pipe one by one, with the cutting edge (small diameter end) of the sleeve at least 3mm away from the pipe mouth, and then insert the pipe into the taper hole in the joint body until it reaches the end;(4) Slowly tighten the nut while rotating the pipe until it stops moving, then tighten the nut 2/3-4/3 turns;(5) Open and check if the card sleeve has been inserted into the pipe and if the position is correct. The card sleeve is not allowed to move axially and can rotate slightly;(6) After passing the inspection, tighten the nut again.

High pressure card sleeve ball valve is suitable for controlling the opening and closing device of medium in medium and small diameter pipelines under pressure, temperature, and medium; By relying on the pressure of the medium to press the sphere onto the outlet valve seat, its usage pressure and diameter are limited to a certain extent. It adopts a 90 ° transmission, so the switch is convenient and quick, and can be quickly opened and closed.1. Through threaded mechanical propulsion, the forward movement of the sleeve nut pushes the rear sleeve forward, while the rear sleeve pushes the front sleeve forward.2. The high-pressure card sleeve ball valve has a smooth and flat channel, which is convenient for pipeline cleaning and can transport media such as slurry and solid particles.3. Using PTFE (Teflon) and other materials as seals, it has lubricity and elasticity, low friction with spheres, and long service life.4. Quick opening and closing, simply rotate the sphere 90 ° for convenient and quick opening and closing.5. The fluid resistance of high-pressure sleeve ball valves is small. When fully opened, the cross-sectional areas of the ball channel, valve body channel, and connecting pipeline are equal and straight, and the medium flows through the ball valve, which is equivalent to flowing through a straight pipe. The fluid resistance of the ball valve in the valve is small.6. High pressure sleeve ball valves are used in water treatment equipment, chemical equipment, petrochemical equipment, petroleum equipment, papermaking equipment, and so on. When the sleeve nut moves forward, it pushes the rear sleeve forward, and at the same time, the rear sleeve pushes the front sleeve forward.