Description

Introduction

In the oil and gas industry, pig signalers play a crucial role in detecting the passage of cleaning pigs within pipelines. These instruments provide valuable information to operators, helping them monitor pipeline conditions and ensure safe and efficient transportation of oil and gas. Among the different types of pig signalers available, the Pig Signaller-20mm Adjustable stands out for its versatility and precision.

Description

The Pig Signaller-20mm Adjustable is an intrusive pig signaler designed to be attached to the pipeline using a flange connection. What sets it apart is its ability to adjust the insertion depth by 20mm, allowing for precise placement within the pipe. This adjustment feature ensures optimal contact with cleaning pigs passing through the pipeline. The Pig Signaller-20mm Adjustable combines a manual reset flag with electrical signals, providing an efficient and reliable means of indicating pig passage. With a bi-directional trigger, it can detect the passage of pigs regardless of the direction of their movement. Additionally, it offers customization options to meet specific customer requirements.

Advantages

The Pig Signaller-20mm Adjustable offers several advantages that make it a preferred choice in the industry:

1. Electrical Signal Integration: By combining the manual reset flag with electrical signals, this pig signaler eliminates the need for close inspection to determine pig passage. The electrical signal can be received from a distance, providing convenience and efficient monitoring of cleaning pig passages.
2. Adjustable Insertion Depth: The ability to adjust the insertion depth by 20mm enhances the precision of the pig signaler. Operators can fine-tune the placement, ensuring optimal interaction with the passing pigs and accurate detection.
3. Flange Connection: Unlike welded pig signalers, the Pig Signaller-20mm Adjustable features a flange connection. This means the material of the signaler’s base does not need to match the pipe material. It only needs to be of the same size to attach securely to the pipe. This flexibility simplifies installation and saves time and resources.
4. Bi-directional Trigger: The pig signaler is bi-directional, meaning it can detect pig passages regardless of the launch or back direction. This feature ensures reliable detection and accurate monitoring of pig movements within the pipeline.

Basic Features and Parameters

The Pig Signaller-20mm Adjustable comes with a range of features and parameters, including:

1. Type: Intrusive
2. Connection type: Flange connection
3. Indicator feature: Manual reset flag combined with electrical signals (customization options available)
4. Installing type: 2” Flange, as per ASME B16.5(CLASS150-2500)
5. Plug body length: 200mm (customizable to meet specific needs)
6. Insert depth adjustment: 20mm
7. Operating temperature: -20~120℃ (customizable according to customer requirements)
8. NACE MR 0175 compliance: Yes
9. Ingress protection: IP66
10. Explosion-proof class: Exd II BT4
11. Remove under pressure: No
12. Trigger type: Bi-directional (customization options available)
13. Internal part material: PTFE Coated A105N (customizable with options such as 304SS/316LSS/DSS/INCONEL)
14. Junction box material: Aluminium alloy/316SS
15. Switch type: DPDT/2*SPDT
16. Switch rating: DC24V 3A/DC24V 5A

Functions

The primary function of the Pig Signaller-20mm Adjustable is to detect the passage of cleaning pigs within pipelines. It is typically installed at the beginning or end of the pipe, where pigs are most likely to enter or exit. When a pig passes through the pig signaler’s location, it triggers a response that is transmitted to the control room, indicating the pig’s passage. This information is vital for pipeline operators to monitor the condition of the pipeline and identify any potential issues or maintenance requirements.

The Pig Signaller-20mm Adjustable provides accurate and real-time information about the location of the cleaning pig within the pipeline. By tracking the pig’s progress, operators can identify and address problems such as corrosion, cracking, or other damage that may require maintenance or repair. Regular inspection and maintenance of pipelines using pigs and pig signalers are essential for ensuring the safe and efficient transportation of oil and gas.

Working Principle

The Pig Signaller-20mm Adjustable operates based on a simple yet effective working principle. Installed inside the pipeline, it interacts with the passing pig physically. As the pig moves through the pipe, it comes into contact with the pig signaler, triggering its mechanism.

At the bottom of the pig signaler is a trigger mechanism designed to be triggered in both directions. When the pig makes contact, the trigger mechanism is activated. It flicks a firing pin and pulls a connecting rod within the sealing bush. This action causes the flag shaft to rotate 90°, transitioning it from a horizontal state to an upright position. The rotation is facilitated by a torsion spring. By observing the flag’s position, operators can determine the location of the pig within the pipeline.

The flag can be reset by manually flipping it counterclockwise, returning it to its horizontal position. This resetting process prepares the pig signaler for the detection of the next pig passage.

Operation Cautions

To ensure accurate and reliable operation of the Pig Signaller-20mm Adjustable, operators should follow some important cautions:

1. Manual Reset: Before using the pig signaler, the flag should be manually reset to the non-triggered state. The flag must be pressed down by the operator, ensuring it is in a horizontal position.
2. Trigger Indicator: If the trigger is pushed by the passing pig, the flag will swing more than 45 degrees, transitioning from a horizontal to a vertical orientation. This indicates that a pig has passed through the pipeline at that specific location.

Choosing between Intrusive and Non-intrusive Pig Signalers

When it comes to selecting the appropriate pig signaler, the choice between intrusive and non-intrusive types depends on several factors, including the type of pig being used, the pipe’s size and material, and the operating conditions.

Intrusive pig signalers, such as the Pig Signaller-20mm Adjustable, are inserted inside the pipeline to physically interact with the pigs. They often use mechanical switches, magnets, or other signals to transmit the trigger when in contact with the pig. Intrusive pig signalers require a special fitting to be installed in the pipeline, allowing their insertion and removal. While the installation procedures for intrusive pig signalers may be more complex, they provide accurate and reliable pig detection.

On the other hand, non-intrusive pig signalers are positioned outside the pipeline and do not require physical interaction with the pigs. They can be set up at various locations along the pipeline without the need for special fittings. While non-intrusive pig signalers offer easier installation and maintenance, they may not provide the same level of accuracy and reliability as their intrusive counterparts.