The modern process plant is a marvel of mechanical, electrical, chemical, and process engineering. Its efficient and safe operations require meticulous and strict control of the condition of the space within the pipelines or vessels storing a myriad of different petrochemical products.
It is easy to understand the distress, even panic, to plant operators when a foreign object is accidentally dropped into process pipelines or vessels during maintenance. These foreign objects can be anything from a wrench, loose nuts & bolts to PPEs such as gloves, safety goggles, etc. Often the location where the foreign objects lands are inaccessible to the maintenance crew, and the impact of such an incident can be especially costly if these foreign objects cannot be easily retrieved.
The JAWS 2.0, by Sensor Networks Inc (SNI), is a set of remotely operated gripper tools designed for the easy retrieval of foreign objects from inaccessible spaces. These tools are commonly referred to as FOSAR (Foreign Objects Search and Retrieval) Tools.
JAWS 2.0’s Call to Duty
JAWS 2.0 was able to demonstrate its value in an unplanned actual application in June this year when a major petrochemicals process plant in Singapore was performing its annual shutdown.
During the maintenance of the plant’s boiler, a helmet torch worn by a service technician became dislodged and dropped into an uncovered flange opening of a 12-inch vertical boiler tube. The boiler tube runs approximately 13 meters vertically down from the flange opening. The vertical section is connected to a horizontal section via a 90° elbow at the bottom.
Given the depth and dimensions, accessing the helmet torch would be a challenge. To exacerbate matters, the incident occurred towards the end of the annual shutdown, giving the plant very limited time for resolution. Extension of the plant shutdown period will be extremely costly.
Months prior to the incident, SNI’s Singapore sales team presented the JAWS 2.0 to the plant inspection team. The Singapore team with JAWS 2.0 was mobilized. In the meantime, the plant maintenance continued to find ways to identify where the helmet torch was located at the bottom of the boiler tube and how to retrieve it, but they had limited success.
SUCCESSFUL RETRIEVAL OF THE FOREIGN OBJECT
The Singapore team arrived on site with JAWS 2.0 a few hours after the incident. The JAWS 2.0 Gripper Tool was deployed using carbon-fiber rods (part of the toolset) and lowered into the boiler tube.
The helmet torch was successfully located at the bottom of the horizontal section of the tube approximately 1 meter from the 90° elbow using the HD camera on the Gripper Tool. After locating the helmet torch and confirming that the whole torch was intact and not broken up into loose smaller pieces, it was retrieved remotely using the Gripper Tool. The entire location and retrieval operation took only one try and less than 15 mins.
Ms. Marie Kwok, Sales Manager VISCOY, who performed the retrieval shared, “The integrated HD camera & lighting was extremely helpful during the retrieval process as it was able to accurately locate the object in complete darkness. After locating the FO, the Gripper was able to easily grip onto and retrieve the FO.”
AFTER ACTION REVIEW
The plant maintenance team, following the retrieval, shared that apart from JAWS 2.0, their only other option was to cut the horizontal section of the boiler tube for FO retrieval. Without a precise location of the FO, there was a risk of cutting the tube at the wrong location. Such a cut and replacement of boiler tubes is estimated to cost between SGD 50,000 to SGD 100,000 not including the cost of extending the plant shutdown and delaying process operations.
The value of JAWS 2.0 is clearly established in this successful retrieval. Recapping the plant management opined that the key features that made JAWS 2.0 so effective are:
- Integrated Camera and Lighting which enabled easy identification and location of FO.
- Simple controls to easily operate the Gripper.
- Complete set of end-effectors and accessories for a wide range of retrieval operations.
