Introduction
This blog is designed to explain the storage • installation • test • maintenance of all the Sleeved plug valves. You must comply after reading the full post to maintain and manage the Lined plug valve for a long time.
What is a Sleeved Plug Valves?
This is a non-lubricated type of Sleeved Plug valve that utilizes a sleeve component installed around the valve plug to maintain a regular seal. The sleeve is utilized to provide the lubricity required for the plug to rotate freely resulting in fast opening and closing of fluid flow.
Sleeved plug valves fabricated also use this sleeve to help reduce frequent maintenance required in the lubricated kind of valves as well as give the valve a long service life. Sleeved plug valves are quarter valves.
This is due to they operate by turning the valve plug at a 90o degree angle to open and close. This kind of valve operates manually or by using of actuators. Sleeved plug valves are designed so that the plug moves up slightly when opening fluid flow to ensure it leaves some clearance with the valve seat to stop wear which can reduce the service life of the plug.
This kind of valve has a tight shut-off and is utilized in different industrial applications like waste water treatment, food processing, chemical processing, and oil and gas among others.
Installation Of Sleeved Plug Valves
The Sleeved Plug Valves Before installation, examine the valve for in-transit damage, damaged valves shall not be set up. To carry the valves right arrangements should be made which can keep the load. The valve should be installed with the groundwork.
Flange-type valves should be fitted parallel with the counter flange and standard gasket. The bolts to fit should be tightened by a diagonal axis successively.
Don’t forget to always follow the guidance mentioned in the attached plates.
Attention During Installation
- Pay attention to use correct way to tightening torques as mentioned in the figure.
- Completely aligned pipe connections cause leakage, and fissuring rupture while utilizing under pressure.
- Check the proper material grade on the nameplate or body to verify the compatibility of fluids with the valve.
| Size -NPS (DN) | Torque NM at ΔP=20 bar for class 150 | Torque NM at ΔP=50 bar for class 300 | CV-Values |
|---|---|---|---|
| 1/2″ (15) | 12 | 12 | 10 |
| 3/4″ (20) | 12 | 12 | 10 |
| 1 ” (25) | 25 | 12 | 48 |
| 1.5″(40) | 35 | 25 | 98 |
| 2“(50) | 75 | 35 | 190 |
| 3″ (80) | 120 | 75 | 330 |
| 4“(100) | 240 | 120 | 630 |
| 6″(150) | 450 | 450 | 1200 |
| 8″ (200) | 785 | 785 | 1900 |
Commissioning and Operation
- The Sleeved Plug Valves should be operated under trained personal. Basically, the Plug valves have been tested for leaks with air or water. Before the initial operation check body bolting. Unless otherwise agreed, there collective be residual amounts of water in the running section of the valve; this could result in a possible action with the medium. To prevent leakages, all connection screws must be checked and retightened if required after the initial loading of the valve.
- If the valve is equipped with a locking application, only the concerned operator or the operator should keep the key. In case the device wants maintenance, it should be done straight away.
- After installation, the Sleeved Plug Valves shall be fully opened & should remain in this fully open condition until lines are thoroughly cleared and flushed. During operation, take care shall be taken not to adjusted the adjusting bolts and cover bolts except for operators.
- Do not remove any device/attachment from the Sleeved Plug Valves under any circumstances.
- The operation shall be stopped in case of error observations. The application condition must be observed; for example, the pressure limitation & the material application.
- The inspection of the functions shall be carried out periodically always right before the operation of the Sleeved Plug Valves.
- The maximum force needed at the hand wheel or wrench to apply the breakaway torque not exceed 360N
Maintenance Of Sleeved Plug Valves
All repair work is to be performed by qualified personnel utilizing the appropriate tools. Basically recognized practice in mechanical engineering is to be observed.
- For the course of action, assignment, and thing numbers of all parts of the valve allude figure.
- Save parts are to be requested with all the points of interest in acc. with the valve identification.
- As it were unique save parts may be introduced. To avoid spills, a standard check of the connection’s crews should be made in line with the working prerequisites. For torque values allude torque table
Trouble shooting
Plug valve does not work: Check for the taking after points
- Is the actuator being provided with power?
- Is any directional control valve associated correctly?
- Is there any remote matter within the valve?
The Plug now not closes totally: Check for the taking after points
- Is the stem deformed?
- Is the coupling worn?
With worm equipment or actuator, check whether the conclusion stops can be re-adjusted. The working manuals of the adapt and actuator producers contain precise instructions.
Never apply constrain to the lever or utilize an extension.
- Attempt to induce the plug valve working once more by moving the lever to and fro.
- Evacuate the lever stop and attempt to switch against the ordinary course of rotation.
- In case activation isn’t conceivable with the max. acceptable breakaway torque as per table 3, destroy the plug valve and assess person’s components
Dismantling Plug Valve
- Now open screw-12 of bonnet-3 with respective torque wrench.
- Next, Open the top four screws of bonnet-3 with the assistance of a designated size torque wrench & now remove the bonnet.
- Now evacuate the parts consecutively as appeared in cross-section 1 view beginning with pushed plate-4, at that point
- Presently evacuate the parts successively as appeared in cross-segment 1 see beginning with pushed plate-4, then cup spring-5, weight plate-6, O-ring-7, stomach plate-8, diaphragm-9, wedge Ring-10 and V-ring-11.
- O-ring (Allude S. No: 7 of cross area) has distorted shape or not,
- Container spring (Allude S. No: 5 of cross segment) are not in distorted shape.
- Presently evacuate the Plug Gradually (Allude S. No:2) with the assistance jacking arrangement.
- Check Plug surface for scratches
- Check that PTFE is scratch free and tidy free.
- Now clean the parts appropriately with the assistance of cleaner.
Plug Valve with Actuator
- Remove Actuator and coupling
- Loosen the jolts and evacuate the brackets.
Plug Valve with Gearbox
- Remove the Gearbox and coupling.
- Extricate the bracket jolts and expel the brackets
Assembling Plug Valve
Now, embed the plug-2 into the body-1 and make beyond any doubt the plug harbour and body harbour are inline. And the Plug is free from scratches and burrs.
Once this is often press the plug-2 interior the body-1 with the assistance of a water powered press, this will offer assistance in the proper settling of plug interior the body. The checkpoint is both the Plug harbour and body harbour will coordinate each other. The pressure to be applied see the table below.
| Valve Size | Pressure (Kg/CM2) |
|---|---|
| 0.5″ | 0.3 |
| 0.75 | 4 |
| 1″ | 5 |
| 1.5″ | 4.7 |
| 2″ | 10 |
| 3″ | 10 |
| 4″ | 15 |
| 6″ | 30 |
| 8″ | 40 |
Presently clean the beat surface of the plug and begin putting the different parts beginning from V-ring-11, Wedge ring-10, Diaphragm-9, stomach plate-8, O-ring-7, Weight plate-6 and Glass spring-5. The grouping of collecting all the parts ought to coordinate with the portrayal given within the cross-section 1.
Put the bonnet-3 and fix the screws with the assistance of torque torque. Torque ought to be connected as per underneath specified values.
Presently, put the beat three screws-12 and fix it to guarantee zero stem spillage. For Fixing torque allude picture 1 underneath.
Assembling with the lever
- Put the lever in arrangement with the plug heading and put the mounting bracket.
- After get together with lever check for the valve working.
Assembling with the Actuator
Mount bracket with the opening at right point to the heading of stream. See sectional drawing in Mount coupling and actuator. Watch the actuator position in understanding with the actuator working manual. Watch the Plug position in understanding with the position of the actuator.
Alignment: In the event that the actuator is fall flat open; valve will be in open position and actuator will be closed. In case the actuator is fall flat closed; at that point both valve and actuator will be in closed position.
