This case happened in a prominent refinery in India, During routine operations, a critical leak was detected at a welded joint on a Venturi Flow Transmitter (FT) line handling Propylene. The defect posed a high-risk scenario, as even a minor failure could have led to a complete plant shutdown, resulting in significant production and financial loss. 

Key technical details of the line were as follows: 

• Line Size: 34″ × ¾”, 300# 

• Media: Propylene 

• Operating Conditions:  

• Pressure: 12.0 kg/cm² (Operating) | 18.60 kg/cm² (Design) 

• Temperature: 30°C (Operating) | 84°C (Design) 

• Type of Defect: Crack at weld joint 

• Criticality: Extremely high (Shutdown imminent) 

Conventional repair options such as line isolation or replacement were not feasible due to operational constraints and time sensitivity. 

Solution Approach 

Nicco Engineering proposed and executed a nonstandard, specially fabricated clamp solution, designed specifically for the geometry and constraints of the Venturi FT assembly. 

Key aspects of the solution included: 

• Custom clamp design and fabrication without requiring any site modification 

• Precision dimensional control, ensuring a perfect fit on first installation 

• Online Leak Sealing (OLS) to eliminate the defect while the plant remained operational