Heat exchangers are critical components in many industries that require transferring heat between two fluids. Over time, these shell-and-tube heat exchangers may develop leaks, requiring effective repair methods like tube plugging.
Although tube plugging can be a reliable solution, it must be carried out precisely to avoid possible issues and further damage to the heat exchanger. In this article, you’ll learn about heat exchanger plugging, types of plugs, and more.
6 Steps for Heat Exchanger Tube Plugging
Step 1: Identifying the Leaking Tube
The first step in the tube-plugging process is identifying the leaking tube. Signs of corrosion and using a tube leak test gun can help pinpoint the problem tube. Once found, it should be isolated from the rest of the tubes in the heat exchanger.
Step 2: Cleaning the Tube’s Interior
To prepare for plugging, thoroughly clean the interior of the tube where you’ll install the plug. Removing debris and corrosion is highly important for achieving a proper seal.
Step 3: Venting the Tube
Venting the tube is a critical precautionary measure before plugging. A small puncture is made inside the tube to release trapped pressure or chemicals. This step reduces the risk of pressure build-up.
Step 4: Plugging the Tube
The actual plugging process can be carried out using several methods, with one common approach being a mechanical plug. This plug is inserted into the tube and expanded to create a secure seal.
Step 5: Checking for Leaks
After plugging, it is important to perform a pressure test on the heat exchanger to check for any leaks and guarantee the effectiveness of the repair.
Step 6: Returning to Service
Once the heat exchanger passes the pressure test without leaks, it can be safely returned to service.
3 Types of Heat Exchanger Plugging Methods
There are three primary methods for heat exchanger tube plugging, each with its advantages and considerations:
- Tapered Plug: This method involves using a tapered pin or one-piece plug. The plug is tapped into the tube until achieving metal-to-metal contact. Although this method is effective, improper installation could lead to tube sheet cracking or splitting.
- Ring & Pin: This approach uses a two-piece plug consisting of a bushing (ring) inside the tube and a tapered plug (pin) hammered in through the bushing. The secondary ring increases the sealing area, improving the plug’s effectiveness.
- Mechanical Plug: The mechanical plug creates a positive mechanical seal as it expands inside the tube. This method is suitable for higher-pressure applications and can be carried out quickly without causing damage to the tube or tube sheet.
The Importance of Proper Plug Installation
Guaranteeing the correct installation of tube plugs is of utmost importance to avoid potential problems, such as the following:
- Creating New Leaks: Improper cleaning or insertion of the plug may lead to new leaks in the heat exchanger.
- Damage to Tubes: Forceful insertion of the plug could damage the tube or tube sheet coating, thereby causing the need for replacements.
- Increased Pressure: Failure to vent the tube before plugging can result in over-pressurization, leading to leaks, damage, or even explosions.
Purchase Top-Quality Tube Plugs at Jorgensen Nano Technology (JNT)
When dealing with tube plugging, rely on Jorgensen Nano Technology (JNT) for top-quality tube plugs that suit a variety of applications. Our high-quality products help ensure your operation runs smoothly without leaky tube issues.
JNT specializes in marketing performance and maintenance equipment globally, catering to the power generation and energy industry. We have a history of successful research and design projects, and we can develop or adapt systems/products based on your plant’s specific requirements, whether electrical, mechanical, or Nano Technology principles.
Our products Include:
- Infrared boiler/furnace thermometers
- Generator bus bar thermometers
- High- and low-pressure plugs
- Electric load distribution centers