Online Leak Sealing – NICCO ENGINEERING SERVICES LIMITED

Online Leak Sealing of a 1-Inch High-Pressure Steam Line in a Refinery

admin — Wed, 14 Oct 2026 09:13:56 +0000

In a refinery, a leak was detected on a 1-inch steam line operating under high-pressure service. The line was carrying steam at 130 bar pressure and 160°C temperature, making the leakage a serious operational and personnel-safety concern.

Although the line size was small, the operating pressure made the situation critical. At 130 bar, even a minor leak can discharge steam at high velocity, creating burn hazards, equipment exposure risks and the possibility of progressive deterioration around the leak point.

Immediate shutdown and line isolation were not preferred due to the refinery’s operating requirements. The plant required an engineered online leak sealing solution that could arrest the leak safely while maintaining process continuity.

Nicco Engineering Services Limited carried out the repair using a solid box clamp fabricated in its own workshop and NES-2B sealing compound injected under controlled conditions.

The Engineering Challenge

High-pressure steam leaks demand immediate attention because of the risk they pose to personnel, nearby instruments, insulation and adjacent equipment.

In this case, the small line size did not reduce the seriousness of the job. A 1-inch line operating at 130 bar can release steam with considerable force. The repair arrangement had to provide reliable containment while allowing controlled injection of sealing compound into the leakage path.

The key challenges were:

sealing a high-pressure steam leak without shutdown;
designing a compact but robust clamp for a 1-inch line;
ensuring the clamp could withstand injection pressure and service conditions;
preventing uncontrolled steam escape during installation;
selecting a suitable compound for the pressure, temperature and service medium;
completing the work safely within refinery operating constraints.

Clamp Design and Fabrication

A solid box clamp was selected for this high-pressure application. Compared with light-duty enclosure arrangements, a solid box clamp provides a more robust sealing cavity and better mechanical containment for demanding pressure conditions.

The clamp was fabricated in NESL’s own workshop based on the line size, leak location, available access and required injection arrangement. The design allowed the clamp to fully enclose the affected section and create a controlled cavity for compound injection.

For high-pressure applications, the clamp is a critical part of the pressure-containing repair system. It must be suitable not only for the operating pressure and temperature, but also for the additional forces developed during compound injection.

The Online Leak Sealing Approach

After site assessment, the solid box clamp was installed around the leaking portion of the 1-inch steam line. The clamp was secured to establish a controlled sealing cavity around the leak point.

NES-2B sealing compound was then injected through the provided injection point under controlled pressure. The injection was carried out progressively so that the compound could enter the leak path, build resistance and gradually arrest the steam escape.

As the compound occupied the leakage route, the steam discharge reduced and was finally stopped. The work was completed online, without removing the line from service.

Result

The online leak sealing operation successfully arrested the high-pressure steam leak.

Following completion:

the leakage was stopped;
the 1-inch steam line remained in service;
refinery operation continued without interruption;
personnel exposure to high-pressure steam was reduced;
an unplanned shutdown was avoided;
the plant gained time to plan permanent repair during a suitable maintenance window.

Why This Repair Matters

In refinery operations, steam lines support critical heating, tracing and process functions. Even a small-bore line can become a major concern when it operates at high pressure.

This case demonstrates that successful online leak sealing depends on the complete engineered arrangement: site assessment, clamp design, workshop fabrication, compound selection and controlled field execution.

The sealing compound alone is not the solution. For high-pressure service, the clamp must be designed and fabricated to create a reliable containment cavity and withstand the combined service and injection loads.

Online Leak Sealing of Ammonia Vapour and Carbamate Liquid Leak from a 1.8 m Flange in a Chemical Plant

admin — Wed, 14 Oct 2026 08:54:25 +0000

In a chemical plant, a major leakage was observed from a large-diameter flange handling ammonia vapour and carbamate liquid. The flange had an outside diameter of approximately 1.8 metres, with a significant gap of around 32 mm between the flange faces.

The equipment was operating at 75 bar pressure and 170°C temperature. Due to the hazardous nature of the process medium and the high operating pressure, the leakage presented a serious safety, environmental and production-continuity concern.

Conventional repair would have required shutdown, isolation, depressurisation and dismantling of the flange assembly. Given the equipment’s criticality and potential production loss, the plant required an engineered online leak-sealing solution that could arrest the leakage while the system remained in operation.

NESL responded with a bespoke clamp-based online leak sealing solution, supported by in-house clamp design, workshop fabrication and controlled injection of NES-2B sealing compound.

The Engineering Challenge

This was not a routine flange leak. The large flange diameter, wide flange gap and hazardous service made the job technically demanding.

A 32 mm gap between flange faces creates a substantial leakage path. At 75 bar, the escaping ammonia vapour and carbamate liquid could not be treated as a minor gasket leak. Any uncontrolled discharge had the potential to expose nearby personnel, accelerate corrosion around the joint, affect adjacent structures and force an unplanned shutdown.

The repair had to address several critical factors:

containment of a hazardous ammonia and carbamate service;
sealing of a wide leakage path around a large-diameter flange;
controlled injection without over-stressing the existing flange assembly;
compatibility of sealing compound with the process medium and temperature;
safe installation of the clamp under live plant conditions;
restoration of containment without disturbing plant operation.

The photographs show the scale of the flange and the complexity of the installed clamp arrangement. The solution required accurate site measurement, proper sealing cavity design and careful planning of injection points around the circumference.

Bespoke Clamp Design and Fabrication

Based on site dimensions and the leakage geometry, NESL designed a bespoke clamp suitable for installation around the 1.8 m OD flange.

The clamp was fabricated in NESL’s own workshop, allowing the repair to be tailored to the actual flange profile, available clearances, bolt layout and sealing requirement. The clamp was designed to create a controlled sealing cavity around the leaking joint and to provide multiple injection points for uniform distribution of the sealing compound.

For such applications, clamp design is an integral part of the repair. The clamp is not merely a cover; it becomes part of the temporary pressure-containing sealing system. Therefore, the design and fabrication approach considered the operating pressure, temperature, flange condition, installation constraints and compound injection requirements.

The Online Leak Sealing Approach

After fabrication, the bespoke clamp was transported to site and installed around the leaking flange. Once the clamp was secured in position, injection fittings were prepared for controlled introduction of the sealing compound.

NES-2B compound was selected for the application considering the process medium, operating pressure and temperature.

The compound was injected progressively through the installed injection points. The objective was to allow the compound to travel through the sealing cavity and occupy the leakage path between the flange faces. Injection was carried out in a controlled sequence to build sealing resistance gradually and avoid sudden pressure imbalance within the clamp cavity.

As the compound filled the leakage path, the discharge of ammonia vapour and carbamate liquid reduced progressively. Injection continued until the leakage was fully arrested and the joint condition was stabilised.

The repair was completed online, without dismantling the flange and without requiring immediate shutdown of the equipment.

Result

The online leak sealing intervention successfully arrested the ammonia vapour and carbamate liquid leakage from the large-diameter flange.

Following completion:

the hazardous leak was contained;
the equipment remained in service;
an unplanned shutdown was avoided;
exposure risk to operating personnel was reduced;
process loss and environmental risk were controlled;
the plant gained time to plan permanent maintenance during a scheduled shutdown.

Why This Repair Matters

Large-diameter flange leaks in ammonia and carbamate service are among the more challenging online leak sealing applications. The risk is not limited to product loss. Such leaks directly affect plant safety, equipment integrity, environmental compliance and production reliability.

This case demonstrates the importance of combining field assessment, engineered clamp design, in-house fabrication and controlled compound injection. The sealing compound alone is not the solution. Successful online leak sealing depends on the complete engineered arrangement: clamp design, sealing cavity, injection strategy, compound selection and safe field execution.

For chemical and fertilizer plants, this approach provides a practical means of maintaining containment and avoiding costly production interruption where shutdown-based repair is not immediately feasible.

Standards and Engineering Reference

Online leak sealing of pressure equipment should be approached as an engineered temporary repair. The repair philosophy should consider applicable pressure containment principles, ASME PCC-2 guidance for repair of pressure equipment and piping, and relevant Indian requirements such as BIS IS 18159:2023 covering online leak sealing compounds and clamp / enclosure design.

In this case, the bespoke clamp and NES-2B injection system were applied as an engineered sealing arrangement to restore containment under live operating conditions.

Online Leak Sealing of Hot Ammonia Separator Flange in a Chemical Plant

admin — Wed, 14 Oct 2026 08:36:01 +0000

In a chemical plant, leakage was observed from the bolted cover / flange region of a Hot Ammonia Separator. The equipment was operating under high-pressure service, with a process gas mixture containing Hydrogen, Nitrogen and Ammonia.

The operating pressure of 150 bar made the leakage a critical maintenance and safety concern. Although the operating temperature was moderate at 40°C, the nature of the process medium made the job highly sensitive. The gas mixture contained approximately 54.85% Hydrogen, 18.235% Nitrogen and 12.959% Ammonia, requiring a carefully controlled sealing operation under strict site safety conditions.

For the plant team, immediate shutdown and dismantling of the flange assembly was not a preferred option due to the production impact and the complexity of isolating high-pressure process equipment. NESL was called upon to carry out an online leak sealing intervention while the equipment remained in service.

The Engineering Challenge

A leak on a high-pressure ammonia separator presents a different level of risk compared with ordinary utility leaks.

The concern was not only the visible loss of process gas. The equipment was handling a hazardous gas mixture containing Hydrogen and Ammonia. Hydrogen introduces flammability concerns, while Ammonia exposure presents a direct personnel-safety and environmental hazard. At 150 bar, even a small leak path can discharge with significant velocity and may worsen if not addressed quickly.

The photographs show a heavily weathered bolted cover area with multiple injection fittings installed around the leakage zone. The sealing arrangement had to consider the existing flange geometry, available access around the cover, bolt layout, leakage path and the need to introduce sealing compound progressively without imposing uncontrolled stress on the joint

The repair therefore required:
– safe execution on pressurised equipment;
– identification of the active leakage path;
– controlled installation of injection points around the flange / cover region;
– selection of a compound compatible with the service and operating conditions;
– gradual injection to avoid sudden pressure imbalance;
– verification that the leak had been arrested before demobilisation.

The Online Leak Sealing Approach

NESL’s service team first assessed the leakage pattern, flange condition and accessibility around the separator cover. Since the equipment was in live service, the intervention had to be planned to maintain containment throughout the operation.
Injection fittings were positioned around the affected region to create a controlled path for introducing the sealing compound into the leakage zone. NES-2B compound was selected for the application based on the service conditions and the nature of the process medium.

The sealing compound was injected in a controlled and sequential manner. Rather than applying excessive force at one point, the compound was progressively introduced through the prepared injection points so that it could migrate into the available leak path and build resistance within the joint cavity.

As the compound occupied the leakage path, the gas discharge was gradually reduced. Injection was continued until the leakage was fully arrested and stable sealing was achieved.

The work was carried out online, without dismantling the equipment and without requiring an immediate shutdown of the plant.

Result
The online leak sealing intervention successfully restored containment at the hot ammonia separator.

Following completion:
– the leakage from the separator cover / flange region was arrested;
– the equipment continued to remain in operation;
– an unplanned shutdown was avoided;
– exposure risk to personnel was reduced;
– loss of process gas was stopped;
– the plant gained time to plan permanent inspection and maintenance during a scheduled shutdown.

Why This Repair Matters

In chemical and fertilizer plants, high-pressure equipment leaks can have consequences far beyond the visible leak point. A leak involving Hydrogen and Ammonia can create safety, environmental, reliability and production risks within a very short time.

This case demonstrates the value of engineered online leak sealing when immediate shutdown is impractical. The sealing compound alone is not the solution. Successful online leak sealing depends on correct assessment of the leak geometry, appropriate compound selection, controlled injection pressure, safe execution practices and experienced field judgement.
For plant maintenance and asset integrity teams, such interventions provide a practical way to regain containment and maintain process continuity until a permanent repair can be planned.

Standards and Engineering Reference

Online leak sealing should be treated as an engineered temporary repair and not as a casual maintenance activity. In such applications, the repair philosophy should consider the principles of ASME PCC-2 for pressure equipment repair, applicable pressure containment requirements, and relevant Indian practices such as BIS IS 18159:2023 for online leak sealing compounds and clamp / enclosure design.

In this case, the repair was executed with due consideration to the live operating condition, process hazard, pressure boundary and sealing compound performance.

Arresting a High-Temperature Steam Leak at a Severely Corroded Safety Valve Bonnet Flange

admin — Fri, 09 Oct 2026 09:02:59 +0000

An engineered online leak sealing solution using an in-house designed and fabricated ring clamp and NES–2F high-temperature sealing compound.

In a renowned power plant in India, a severely corroded bonnet flange on a 6-inch safety valve was releasing high-temperature steam and condensate through a circumferential gap exceeding 14 mm. With the system operating at 14 kg/cm² and 350°C, the leakage represented an immediate personnel-safety concern, a significant source of energy loss and a potential trigger for an unplanned shutdown of a critical process unit.

For the plant’s maintenance and asset integrity team, the challenge was not simply to arrest the leakage. It was to find a technically suitable intervention that could address the deteriorated flange joint while preserving process continuity and avoiding the production losses associated with isolating the equipment.

Nicco Engineering Services Limited (NESL) responded with a bespoke online leak sealing solution, combining in-house clamp engineering and fabrication with a high-temperature sealing compound to contain the leakage without a planned process shutdown.

The Challenge: Severe Flange Deterioration Under Live Operating Conditions

The leakage originated at the bonnet flange joint of a 6-inch safety valve. Extensive corrosion had compromised the joint geometry, leaving a circumferential leakage path with a local opening exceeding 14 mm.

Unlike a conventional gasket leak, where controlled bolt tightening or gasket replacement may restore sealing under suitable isolated conditions, this case involved significant deterioration of the flange assembly itself.

The continuous discharge of steam and condensate created several operational concerns:

Personnel safety: Exposure to high-temperature steam and condensate presented a serious burn and scalding hazard.
Energy losses: Continuous steam escape represented a direct loss of thermal energy and boiler-generated steam, with preliminary estimates indicating losses worth several thousand rupees per hour.
Equipment deterioration: Prolonged leakage could accelerate damage to adjacent components, insulation and supporting structures.
Production continuity: Conventional flange repair would require equipment isolation and potentially a process interruption, depending on the plant configuration.
Escalating maintenance costs: Delaying corrective action could increase the scope and cost of eventual flange refurbishment or replacement.

With the equipment remaining in operation, conventional joint dismantling and gasket replacement were not immediately practical.

The plant therefore required a repair approach that could contain the leakage while avoiding an unscheduled shutdown, subject to engineering assessment and the site’s safety requirements.

Emergency Response and Technical Assessment

Following the emergency request, NESL’s Online Leak Sealing Response Team mobilised and arrived at the plant within a few hours.

The initial site assessment focused on understanding the leak geometry, the operating conditions and the feasibility of installing an external sealing enclosure around the damaged bonnet flange.

Operating and leakage conditions

Parameter	Site condition
Equipment	Safety Valve
Nominal valve size	6 inches
Leakage location	Bonnet flange joint
Process medium	High-temperature steam and condensate
Operating pressure	14 kg/cm² (approximately 13.7 bar)
Operating temperature	350°C
Nature of damage	Severe corrosion and flange deterioration
Leakage pattern	Continuous circumferential leakage
Local flange gap	Greater than 14 mm
Proposed intervention	Bespoke ring clamp with injected sealing compound

The size of the opening and the deterioration of the existing joint made the repair particularly challenging. An external enclosure had to accommodate the damaged geometry and provide an effective sealing boundary under elevated temperature and pressure.

The assessment also required consideration of the remaining integrity of the existing flange, the mechanical and thermal loads on the proposed enclosure, and the need to preserve the safety valve’s essential operating function.

Based on the site conditions, NESL proposed a custom-engineered ring clamp combined with an appropriate high-temperature sealing compound as the preferred containment methodology, subject to the necessary plant approvals.

NESL’s Engineered Solution: Bespoke Ring Clamp and High-Temperature Sealant

1. Custom Clamp Design and In-House Fabrication

The damaged flange geometry required a purpose-built enclosure rather than a standard off-the-shelf repair clamp.

NESL’s engineering team developed a bespoke ring clamp configured for the bonnet flange assembly and the observed leakage location.

The clamp design considered the operating pressure and temperature, the available installation envelope, the joint geometry, the mechanical loading of the enclosure and the requirements for an effective sealing boundary.

A key advantage was NESL’s in-house capability to design and fabricate custom-engineered clamps at its own workshop.

This integrated engineering and manufacturing capability enabled the proposed sealing arrangement to be tailored to the actual site conditions while reducing dependence on external fabrication vendors—an important consideration during time-sensitive industrial maintenance interventions.

The design approach was informed by established pressure-equipment repair principles, including:

BIS IS 18159:2023: Online Leakage Sealing Systems — Code of Practice.
ASME PCC-2, Article 306: Mechanical Clamp Repair, covering the engineering considerations applicable to mechanical repair clamps.
Applicable ASME pressure-equipment design provisions: Consideration of the relevant construction code and pressure-boundary design requirements for the specific application.

2. Selection of NESL–2F High-Temperature Sealing Compound

NESL selected its proprietary NESL–2F High-Temperature Leak Sealing Compound for the steam-service application.

The compound is specified by NESL for suitable high-temperature applications, with a stated temperature capability of up to 450°C, subject to the applicable product qualification and service limitations.

At an operating temperature of 350°C, the application demanded a sealing material capable of maintaining its intended performance in the presence of steam, elevated temperature and sustained operating pressure.

The selection of the sealing compound was an essential part of the overall repair methodology. The performance of an online sealing arrangement depends not only on the mechanical enclosure but also on the suitability of the sealant for the process conditions and the damaged joint geometry.

3. Controlled Online Sealing Intervention

Following the site safety review and necessary authorisations, the NESL team carried out the online sealing intervention using the purpose-built ring clamp and NES–2F sealing compound.

The repair was undertaken with the objective of establishing an effective containment barrier around the deteriorated bonnet flange without requiring a planned shutdown of the process unit.

The combination of a geometrically matched enclosure and a suitable sealing compound provided an alternative to immediate joint dismantling and gasket replacement.

The principal operational benefit was the ability to address the leakage while preserving plant operation, thereby avoiding the immediate production interruption that could otherwise have accompanied conventional maintenance.

Operational and Commercial Benefits

For plant management, the significance of this intervention extended beyond containing the steam leakage.

Avoidance of an Unplanned Shutdown

By undertaking the intervention online, the plant avoided the immediate need for a planned isolation solely to carry out conventional bonnet flange repair, subject to the continued safe operation of the equipment.

Reduction in Steam and Energy Losses

Containment of the leakage addressed an ongoing source of steam and thermal-energy loss. Preliminary estimates placed the financial impact at several thousand rupees per hour, making timely intervention commercially important.

Reduced Exposure to Escalating Maintenance Costs

Prompt containment reduced continued exposure of nearby equipment and insulation to the escaping steam and condensate, helping limit the potential for secondary deterioration.

Faster Maintenance Response Through In-House Engineering

NESL’s integrated capability for site assessment, bespoke clamp design and workshop fabrication supported a coordinated response to an emergency maintenance requirement.

Improved Shutdown Planning Flexibility

An engineered online intervention can provide the plant with an opportunity to schedule permanent flange refurbishment or replacement during an appropriate maintenance window, rather than allowing the leak alone to dictate an immediate shutdown.

Engineering Perspective: Why This Was Not a Routine Flange Leak

The distinguishing feature of this case was the extent of flange deterioration.

A gap exceeding 14 mm represents a substantially different engineering challenge from minor gasket seepage. It raises questions about the adequacy of the remaining joint, the ability of the proposed enclosure to retain pressure and the compatibility of the repair with the original equipment function.

For online sealing interventions of this nature, established industry practices emphasise the importance of assessing the damaged component, evaluating the suitability of the clamp and sealing system, considering applicable pressure and thermal loads, and establishing an appropriate repair life and follow-up inspection strategy.

ASME PCC-2 provides an internationally recognised technical framework for pressure-equipment repairs, while BIS IS 18159:2023 specifically addresses online leakage sealing systems in the Indian industrial context.

These engineering principles are especially important when repairs are undertaken on safety-critical equipment such as safety valves, where the sealing intervention must not compromise the valve’s protective function.

Conclusion: Containing the Leak Without Compromising Production Continuity

This case demonstrates the value of combining rapid site response, application-specific engineering, in-house clamp fabrication and appropriate high-temperature sealing technology.

By developing a bespoke ring clamp to address a severely deteriorated safety-valve bonnet flange, NESL offered the plant a practical alternative to immediate shutdown-based maintenance.

For asset integrity and maintenance managers, the broader lesson is clear: a properly assessed and engineered online leak sealing intervention can help control urgent leakage, reduce avoidable energy losses and protect production continuity while permanent maintenance is planned.

Through its integrated engineering, fabrication and field-service capabilities, Nicco Engineering Services Limited supports power plants in addressing challenging leakage problems with a focus on safety, equipment integrity and operational reliability.

Online Gland Leak Sealing of a 3-Inch Angle Seat Piston Valve

admin — Tue, 29 Sep 2026 08:53:17 +0000

A gland leak on a valve operating in a high-pressure steam system is more than a maintenance issue. Apart from the continuous loss of steam and energy, an uncontrolled leak can create a serious personnel-safety concern and may progressively affect the surrounding valve components.

At a major power plant in India, a severe steam leak developed from the gland area of a 3-inch Angle Seat Piston Valve. The leakage was traced to the gland packing around the valve stem.

The valve was part of an operating system and immediate isolation or shutdown was not considered feasible. The plant therefore required a repair method that could control the leakage while the valve remained in service.

Nicco Engineering Services Limited carried out an engineered Online Leak Sealing (OLS) intervention to arrest the leak without interrupting plant operation.

Operating Conditions

Equipment: Angle Seat Piston Valve
Nominal Size: 3 inch
Leak Location: Valve gland / gland packing area
Process Medium: Steam
Operating Pressure: 195 kg/cm²
Operating Temperature: 100°C
•
Existing Packing: Metallic gland packing
Leak Sealing Compound: NES Compound 7A

The Engineering Challenge

Gland leaks present a different sealing challenge from conventional flange or pipe-joint leaks.

The leakage path exists around a moving valve stem, and any sealing intervention has to control the escaping process medium without damaging the stem, restricting its movement, or placing uncontrolled loads on the gland assembly.

In this case, the challenge was intensified by the high operating pressure.

The repair therefore had to address several factors simultaneously:

containment of the escaping steam;
retention of the sealing material within the gland region;
controlled introduction of compound into the leak path;
protection of the valve stem and gland assembly; and
safe execution while the system remained pressurised and operational.

The Online Leak Sealing Approach

Before beginning the sealing operation, the gland arrangement and accessible sealing geometry were assessed by the service engineering team.

The existing metallic gland packing formed an important part of the sealing arrangement and provided the necessary mechanical resistance within the gland region.

A suitable injection arrangement was then established around the gland.

NES Compound 7A was introduced through a single injection point under carefully controlled injection pressure.

Rather than simply forcing compound into the gland, the injection was progressively controlled so that the material could migrate into the available leakage path and establish an effective seal around the stem.

As the compound occupied the leak path, the escaping steam was progressively reduced until the gland leakage was arrested.

The work was completed online, without shutting down the operating system.

Result

The intervention successfully restored containment at the valve gland.

Following completion:

the steam leakage was arrested;
the valve remained in continuous service;
an unplanned plant shutdown was avoided;
steam and associated energy losses were stopped;
the immediate personnel-exposure risk around the leaking valve was substantially reduced; and
the valve could remain operational until a permanent inspection and maintenance opportunity during a planned shutdown.

Why This Repair Matters

For power plants, the value of online leak sealing is not simply the elimination of a visible leak.

On critical steam systems, taking equipment out of service can affect generation availability, maintenance planning and plant operating continuity. Where the equipment condition and leak geometry are suitable for online intervention, an engineered leak sealing solution can provide a controlled means of maintaining containment until permanent maintenance can be undertaken during a scheduled outage.

This case also demonstrates an important principle of gland leak sealing: the repair has to be engineered around the existing valve construction, packing arrangement, operating pressure, process medium and available injection path.

The sealing compound alone is not the solution. Successful online leak sealing depends on the complete engineered arrangement and controlled field execution.

Conclusion

The successful sealing of the gland leak on this 3-inch Angle Seat Piston Valve demonstrates the applicability of Online Leak Sealing for selected high-pressure steam valve leaks where immediate shutdown is impractical.

Through assessment of the gland configuration, utilisation of the existing metallic packing arrangement and controlled injection of NES Compound 7A, Nicco Engineering was able to restore containment while keeping the system in operation.

For power plants where equipment availability and personnel safety are both critical, such interventions can provide an effective temporary engineered repair until the equipment can be properly inspected and overhauled during the next planned shutdown.

Emergency Venturi FT Clamp Installation at Propylene Recovery Unit (PRU)

admin — Mon, 13 Apr 2026 07:22:33 +0000

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

The execution was carried out jointly with the Belzona technical team, utilizing proven composite repair materials:

NES5B for primary leak sealing

Belzona 1161 & Belzona 5841 for strengthening and complete peripheral sealing

Belzona 9371 reinforcement tape for additional structural integrity

Execution Highlights

Installation completed without any hot work or unit shutdown

Zero safety incidents during a highrisk operation

Successful OLS injections with no post-installation leakage

Flawless coordination between engineering, site execution, and sealing specialists

Outcome & Client Feedback

The intervention successfully averted a potential plant shutdown, safeguarding continuous operations and preventing major production losses.

Client formally acknowledged Nicco Engineering’s performance, highlighting:

Exceptional technical competence

Meticulous planning and preparation

Strict adherence to safety protocols

Precision execution under critical conditions

This project stands as a strong example of Nicco’s capability to deliver innovative, reliable, and safetydriven solutions for complex, highstakes industrial challenges.

NRV Bonnet leakage in a prominent power plant in India

admin — Thu, 14 Aug 2025 06:03:07 +0000

The Problem

In a critical steam-handling section of a prominent power plant in India, a sudden leakage was identified at the bonnet of a 6-inch Non-Return Valve (NRV). The leak was discharging steam and condensate at 8 bar pressure and 180°C temperature, posing serious hazards to nearby equipment, insulation, and most importantly, operational personnel.

The continuous leakage not only threatened to halt a key section of the process unit but was also incurring significant energy losses. Preliminary estimates indicated an hourly steam loss worth several thousand rupees, with risk of progressive damage to nearby components if left unchecked.

Inspection by NESL team & the Solution Offered

Upon immediate intimation, NESL’s Online Leak Sealing Response Team reached the site within hours and conducted an on-site inspection.

Leak Characteristics:

Leak Location: NRV Bonnet Joint
Line Size: 6 inches
Medium: High-temperature steam
Pressure: 8 bar
Temperature: 180°C
Leak Type: Continuous fissure around bonnet circumference

Proposed Solution:

NESL recommended an online sealing intervention using:

Brass wire peening to close open paths
Injection of high-temperature resistant sealing compound (NESL – ½ A) suitable for steam lines up to 200°C

This solution would ensure zero shutdown and minimum disturbance to plant operations.

4. Safety Mitigation Protocols

The job was executed in strict compliance with NESL’s Online Leak Sealing SOP and BIS IS 18159:2023 industrial safety norms:

PPE compliance: All technicians were equipped with fire-retardant overalls, insulated gloves, face shields, and steam-resistant boots.
Permit to Work (PTW) obtained from client maintenance.
Area isolation with barricading and caution signage
Standby safety observer to monitor team health and emergency response
Continuous temperature and pressure monitoring
Toolbox Talk (TBT) conducted before job initiation

5. Execution of the Job

The job was carried out under the supervision of a senior technician with support from two experienced team members. The leak area was first cleaned and checked for temperature to ensure proper bonding. Brass wire peening was then applied around the NRV bonnet to reduce the leak path and help retain the sealing compound. NESL- ½ A compound, suitable for high-temperature steam lines, was injected using a caulking gun in multiple passes to fully seal the area. The compound began curing within minutes, and the team monitored the zone for 30 minutes to ensure the seal held steady with no further leakage.

6. Re-check and Assurance

After full curing a joint inspection was carried out along with the client’s maintenance head.

The sealed area was visually inspected.
No vapor emission or temperature drop observed.

7. Before and After Images

8. Client Appreciation

The client expressed satisfaction over:

The timely response
Professional execution without shutdown
Cost savings by avoiding valve replacement and downtime

This case once again demonstrates NESL’s leadership inemergency online leak sealing services across Indian industries. By complying with BIS IS 18159:2023 standards, adopting zero-downtime repair techniques, and deploying field-proven sealing compounds, NESL helped the power plant avert serious operational and financial loss.

If you are facing a similar problem at your please feel free to reach out to us: https://www.niccoengineering.com/contact-us/

Efficient Online Leak Sealing of High-Pressure Ammonia Vapour & Carbamate Leak at a 1.8 m Flange

admin — Wed, 02 Jul 2025 06:08:34 +0000

In large-scale fertiliser plants, even a small flange leak can cascade into major safety, environmental, and financial consequences. When faced with an ammonia vapour and carbamate liquid leak at 75 bar and 170 °C, Nicco Engineering’s sealing specialists demonstrated how precise inspection, rigorous safety protocols, and the right sealing compound can arrest a critical leak—without a plant shutdown.

The Challenge

At a urea synthesis facility, a flange joint with an outer diameter of 1.8 m and a 32 mm gap began leaking under full operating conditions. Ammonia vapour posed a severe inhalation risk and environmental concern, while the carbamate liquid drained in volume per day—a significant loss to the client. Shutting down for repairs would have cost hundreds of thousands in lost production and restart logistics. An online sealing solution was essential.

Inspection & Detailed Assessment

Manual Inspection:

Visual confirmation of vapour plume and liquid droplets.
Measurement of flange gap uniformity.

Drawing Verification:

Cross-referenced plant piping and instrumentation diagram (P&ID) and mechanical drawings to verify flange dimensions and spacer alignment.
Identified asymmetry in spacer thickness and bolt-hole alignment as likely contributors to uneven sealing surfaces.

Safety Protocols & Site Preparation

Permit to Work (PTW): Secured hot-work and confined-space clearances.
Personal Protective Equipment: Full-face respirators with SCBA, ammonia-rated gas monitors, and acid-resistant suits and gloves.
Emergency Readiness: Standby spill-control and neutralizing agents on hand.

Sealing Solution & Execution

We selected Compound 2B, a BIS-approved material (per BIS IS 18159:2023) capable of withstanding temperatures to 300 °C. NES 2B was injected using an injection gun, gradually the sealant filled the flange gap thereby arresting the leak.

Results & Validation

Pressure Test: Gradual re-pressurization to 75 bar—no detectable leak or pressure drop.
24-Hour Monitoring: Stable pressure readings without deviation.

Impact & Client Feedback

By executing a rapid, well-orchestrated online seal, Nicco Engineering:

Prevented significant production loss during the shutdown.
Mitigated health and environmental hazards without interrupting plant operations.
Demonstrated compliance with national sealing standards.

“Nicco’s team delivered exceptional expertise and safety diligence—halting a critical leak in hours and saving us significant downtime. Their professionalism and the performance of Compound 2B were outstanding.”

Conclusion
This case underscores the value of detailed inspection, adherence to safety and standards, and the selection of a high-performance sealing compound in addressing severe, high-pressure leaks online—safeguarding both people and productivity.

Immediate Resolution of Hazardous Steam Leakage in a 660MW Power Plant

admin — Mon, 01 Jul 2024 09:14:13 +0000

A renowned 660MW power plant in India experienced a hazardous steam leakage incident. The affected line was operating at a high pressure of 140 bar, carrying steam at a temperature of 230°C. The leakage occurred on the body of the Turbine Driven Boiler Feed Pump (TDBFP) flange, posing a significant risk to the plant’s operations and safety.

Inspection and Solution

Upon receiving the emergency call, our service engineers promptly arrived on-site to assess the situation. After a thorough inspection, they identified that our proprietary compound NES 2C was the optimal solution to arrest the steam leakage instantly. The chosen method for application was the drill and tap technique, known for its effectiveness in sealing high-pressure leaks.

Safety Protocols

Safety is paramount in such high-risk situations. Our team ensured that all safety protocols were strictly adhered to before and during the execution of the job. This included isolating the affected area, wearing appropriate personal protective equipment (PPE), and closely monitoring the pressure and temperature of the steam line throughout the repair process.

Execution

Using the drill and tap method, our engineers carefully applied the NES 2C compound to the leaking flange. The compound’s excellent sealing properties and the precision of the drill and tap technique allowed for an immediate cessation of the steam leakage.

Recheck and Assurance

Following the repair, our team conducted a meticulous recheck to ensure that the leakage had been fully stopped. This inspection confirmed that the repair was successful and that the leak had been arrested effectively, providing a temporary but reliable solution until the next scheduled shutdown.

Client Appreciation

The swift and efficient response by the Nicco online leak sealing team was highly appreciated by the client. The quick resolution of the steam leakage not only ensured the safety of the plant but also prevented an expensive and unscheduled shutdown. The client commended our team for their professionalism, expertise, and the quality of service provided under pressure.

Emergency Online Leak Sealing at a prominent (2x800MW) Power Plant in India

admin — Wed, 29 May 2024 09:16:53 +0000

Introduction

In this case study, we examine a critical incident at a (2x800MW) prominent power plant in India that faced a severe steam leak from a valve gland. The leakage involved steam gushing out at an extreme temperature of 300°C and a pressure of 150 bar. The immediate and efficient response of our online leak sealing team played a pivotal role in resolving this high-risk situation.

Situation Overview

Incident Details

Location: A prominent (2x800MW) power plant in India
Issue: Valve gland leakage
Conditions: Steam leakage at 300°C and 150 bar

Emergency Response

Our service engineers promptly responded to the emergency call. Upon arrival, they identified that the valve gland was exposed to high temperatures and water, causing the leakage.

Challenges Faced

The primary challenges included:

High Temperature: The steam temperature of 300°C posed a significant risk to both personnel and equipment.
High Pressure: The pressure of 150 bar required specialized handling to prevent further damage and ensure safety.
Immediate Action Needed: The critical nature of the leak demanded an immediate and effective solution to prevent operational downtime and potential hazards.

Solution Implementation

Leak Sealing Compound: Our proprietary leak-sealing compound, NES-7A, was chosen to address the leakage. NES-7A is renowned for its effectiveness in sealing leaks under extreme conditions, such as high temperature and pressure.

Procedure

Assessment: The engineers assessed the leakage and surrounding conditions to plan the sealing process.
Preparation: Necessary safety measures were implemented to ensure the safety of the team and the plant.
Injection of NES-7A: The leak sealing compound NES-7A was injected into the valve gland area. Its properties ensure a robust seal even under the harshest conditions.
Monitoring: Post-injection, the area was monitored to ensure the leakage was arrested and no further issues arose.

Outcome

The application of NES-7A successfully sealed the leak. Key outcomes:

Immediate Leak Arrest: The leakage was stopped promptly, preventing potential damage.
Safety Ensured: The high temperature and pressure conditions were managed safely without any incidents.
Operational Continuity: The power plant operations continued without significant downtime, showcasing the effectiveness of the solution.

Our expertise and prompt action ensured the safety of personnel and equipment, while maintaining the power plant’s operational integrity. This incident reaffirms the reliability and efficacy of our leak sealing solutions in the most challenging industrial conditions.