The Beginnings

Before I graduated, I worked at various jobs for ESSO refineries at Mahul, which was near my home in Chembur. I had a big break during that time by producing import substitute LPG bombs for the laboratories. The product was very successful, especially due to the Teflon seating valves that provided as a replacement of needle valves on either side. I received repeat orders and also began supplying to Burmah Shell Refinery and years later ONGC in a very big way. Manufacturing the products at various shops resulted in nearly a 500% profit. After completing my engineering degree, I established a workshop for a proprietorship company called Leo Engineering Works. I secured a loan from MSFC and seed capital from KDF to set up a project for pressure vessels in TTC MIDC. The first order was for a furnace tube sheet for a fired vessel. I noticed the ongoing maintenance of shell and tube exchangers, all imported from the USA. I managed to get an order for drilling tube sheets and thereafter completed shell and tube heat exchangers. In 1975, we became the first company in India to manufacture a shell and tube exchanger, marking a significant milestone. We then secured the entire chain of exchangers for the lube refinery expansion for Lube Oil Base Stock (LOBS) production.

Our involvement with the Screwplug began with discussions about a tragic incident in Japan that led to numerous casualties. Concerns arose about this type of construction, which seemed to evolve over time. Officially known as a breach lock, we refer to it as the Screwplug because it involves screwing a plug onto the channel barrel. Initially, the threads were 4 to 5 per inch, but thread slippage became the primary cause of significant hydrocarbon leakage and explosions. Over several decades, modifications were made, reducing the thread count to one per inch, which remains the standard today.?

While this change improved safety, the construction is still not user-friendly. The large thread size causes galling, particularly on the first thread, resulting in bell mouthing. The only effective way to prevent this is by increasing the wall thickness of the barrel to more than double the standard design for Section VIII, Division 1, and triple for Division 2.

At Tema India, we solved this issue by reinforcing only the threaded portion of the barrel through the shrink-fitting of a steel ring. This innovation has made unscrewing the threads for maintenance significantly easier. Over the past 15 years, we have successfully delivered more than 250 such exchangers, all of which have provided trouble-free service, unlike the products of our global competitors.

We have made an additional modification to the Tema, specifically to our Hi-Hi construction Screwplugs. This modification ensures that the shell-to-tube-sheet joints are 99.999% leak-proof, meeting Euro VI standards to avoid mixups in sulfur-free diesel. To achieve this, we have introduced a unique slot-free design in the channel barrel, along with the implementation of our proprietary 'blokarb' techniques, which effectively isolate the shell side and tube side fluids. This innovation guarantees superior performance and reliability in preventing leaks.

Copyright ? 2024 Haresh Sippy

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