Orbit Orbit Ball Valve Professional Maintenance Details

The Orbit orbital ball valve seems to have a simple structure with only a few simple components, but it has many advantages over other valves. The advantages are as follows:

• Frictionless rotation

• Dual stem guide pins

• Forced sealing - mechanical wedging

•Single seat design

• Optimum flow characteristics

• Self-cleaning

• Cemented carbide surfacing sealing surface can be filled with filler

• Zero leakage

• Low torque, easy operation

• Top-mounted design

•long life

• High reliability

How does such a simple structure achieve so many advantages?

This shows that there are many sophisticated technical points in the seemingly simple, so the Orbit valve has been imitated but never surpassed.

Also for the maintenance of Orbit valves, there are many technical points that need to be paid attention to. They must be repaired, maintained and maintained by professionally trained technicians to ensure that the performance of the valve after repair is improved and the service life is prolonged.  Non-professional maintenance can not only restore the valve performance well, but also may cause secondary damage to the valve, or even cause the valve to be directly scrapped.

for example:

Replacement of valve seat

The valve seat in the main components of the Orbit valve can ensure a seal of more than 6 grades under the working conditions of up to 2500CL, and can withstand frequent switching and extrusion to ensure long-life use. It can be seen that it is not as simple as an ordinary steel ring, it is The treated hollow structure has excellent sealing and elasticity, so in general, when the valve seat is damaged, it cannot be repaired and can only be replaced.

There are also many aspects to pay attention to when replacing the valve seat:

1. Whether the size of the valve seat and the amount of interference are reasonable;

2. Whether the material of the valve seat conforms to;

3. Whether the installation is in place;

Repair of valve balls

The sealing surface of the valve ball is made of hard alloy surfacing, so it is less likely to be damaged than the valve seat, but the valve ball may be damaged when there are hard impurities such as welding slag in the pipeline. After the damage occurs, a repair or replacement plan can be formulated according to the degree of damage.

The maintenance of the valve ball requires professional equipment and personnel, and must meet:

1. First surfacing and then grinding;

2. The welding material is consistent with the original material;

3. After grinding, the original valve ball R value and center high standard parameters cannot be changed;

4. In addition, the wear of valve ball trunnions, fixing pins and other components will affect the working state of the valve, and inspection and maintenance are also required;

Maintenance of the valve stem

    The valve stem is the main part that drives the valve switch. Its wear condition directly affects whether the valve switch is smooth and stable; whether the switch is in place; whether the valve ball fully presses the valve seat, and repairs can be made according to the degree of damage after damage occurs. or change the plan.

The inspection and maintenance of the valve stem requires professionals, and the following points must be paid attention to:

1. The wear of the valve stem guide groove;

2. The wear degree of the wedge-shaped force surface of the valve stem;

3. The surface finish of the valve stem and the strength of the valve stem;

Maintenance and overhaul of the actuator

    The original Orbit actuator is a specially designed actuator according to the working principle of the orbital ball valve, which can perfectly operate the valve action. The assembly of each part of the actuator and its assembly with the valve have precise data requirements. Whether the assembly is standard or not will directly affect the working state of the valve. If the assembly and assembly data requirements are not understood, blindly disassembling and assembling the actuator will change the actuator performance, make the valve work in an abnormal state, affect the performance, shorten the service life, and even directly cause the valve actuator to be damaged and scrapped.

Therefore, the inspection and maintenance of the actuator needs to be carried out by professionals, and the following points must be paid attention to:

1. The disassembly of the actuator needs to be carried out in accordance with the steps of the "Maintenance Manual";

2. The tightening of the actuator fasteners and the preloading of the springs need to be carried out in strict accordance with the factory parameters;

3. The assembly parameters of the actuator and the valve need to be strictly in accordance with the factory parameters;

Our company has a complete maintenance system process, strict maintenance specifications, professional maintenance technology, and excellent maintenance team. We will conduct a detailed investigation and understanding of each valve, and then make reasonable maintenance suggestions in a targeted manner. After the agreement between the two parties, we will formulate a detailed construction plan, and then carry out professional maintenance according to the plan.

Unsuccessful cases of non-professional maintenance

1. Several failures and self-maintenance of Orbit orbital ball valve of a certain unit

1. The 01KV40007 valve does not move smoothly. It is found that the valve ball and valve seat are severely worn when dismantling the valve, resulting in irregular movement of the valve stem, and the edge of the track groove and the guide pin are collided and damaged due to force. Because the on-site valve maintenance personnel could not handle it, apply for an outsourced maintenance of the valve.

2. 2016-9-19  01KV40007 Factory maintenance.

3. On April 1, 2017, the valve is online, the instrument restores the gas source pipe and wiring, and the valve operates normally. There is no internal leakage in the normal valve for the process personnel to boost and reduce the pressure, and the process is put into use.

4. On 017-5-11, the valve was not opened properly. The on-site inspection of the instrument found that the venting pressure of the exhaust port of the diaphragm head was large, and the valve switch operated normally by the handwheel. The maintenance personnel disassembled the diaphragm head and found that the diaphragm sealing ring was damaged and replaced it. Reinstall the membrane head after the sealing ring, test the valve action is normal, and the process is put into use.

5. On May 27, 2017, the valve could not be opened again. The on-site inspection of the instrument found that the exhaust pressure of the exhaust port of the membrane head was high. When the membrane head was disassembled, it was found that one of the diaphragm sealing rings was missing. After filling the sealing ring and reinstalling the diaphragm head, the valve still cannot be fully opened, and the hand wheel cannot be opened either. The reason is that the small gap between the two valve stem guide pins and the valve stem hinders the valve stem movement. The valve operates normally after adding a gasket to shorten the valve stem guide pin. The process is put into use.

6. On June 28, 2017, the valve could not be closed. The instrument on-duty inspected on-site. After shaking the handwheel slightly, the valve was closed. When the valve was opened again, the valve could not be opened. Check the guide pin of the valve stem and find that the top of the guide pin was worn, and the maintenance personnel used a file After repairing, reinstall it, and the test valve operates normally. The process is put into use.

7. 2017-7-5  When the process is ready to switch the hydrogen dryer V-1481 from the B station to the A station, although the DCS of 01KV40007 shows the closed state at this time, the actual valve stem and valve ball are suddenly separated and internal leakage occurs. , causing the hydrogen to enter the fuel gas system from the running station A into the fuel gas system, causing the hydrogen product to be cut off and the fuel gas system to fluctuate, which in turn causes the R-1480 of the methanation reactor to over-temperature interlock and stop, and the expander C-1420 to vibrate high and interlock. , Valve offline inspection and maintenance.

8. It will be handed over to our company for maintenance.

2. Analysis of this maintenance case:

1. Basic maintenance process: The valve is handed over to a non-professional maintenance unit for maintenance. The method adopted is to destructively remove the valve seat and process the valve seat and valve ball by itself. Since the valve seat groove is destroyed when the valve seat is removed, when the valve seat is reinstalled The valve seat groove is processed, the original valve stem is replaced, and the whole valve is assembled with the actuator and put into use.

2. Error points during maintenance:                              

Consequences:

1. Destructive removal of the valve seat; ---------------------------- Damaged the valve seat groove on the valve body, resulting in failure of subsequent maintenance Replace the original equipment normally;

2. Self-processing valve seat and valve ball; ------------------------- valve seat is not as long as it is supposed to be sealed, and self-processing valve seat has no effect. Elasticity and unreasonable force on the valve ball are the reasons for the damage to the valve stem in the later stage.

3. Destroy the valve seat groove; ------------------------------- The original valve parts are matched very accurately, destroying the valve seat groove Cause the valve seat position to change, causing the valve to need to overtravel to ensure sealing.

4. After the whole valve is assembled and the actuator assembly is not installed according to the factory data; -- -- Not installed according to the original factory data, so that the various parts of the valve are unreasonably stressed and eventually damaged.

After non-professional maintenance, not only the maintenance was ineffective, but also aggravated the problem, causing the valve to be almost scrapped from the original internal leakage, which created a lot of difficulties for subsequent professional maintenance.

3. Valve maintenance process in our company:

When the valve was inspected in the factory, the valve stem, valve ball, valve seat, valve stem guide pin, actuator diaphragm, actuator connecting rod, and valve stem sealing ring were all damaged; the valve body was damaged, and the valve was almost scrapped.