how to conduct rbi assessment of gas heater - untuk lingkungan sendiri

7/27/2019 How to Conduct Rbi Assessment of Gas Heater - Untuk Lingkungan Sendiri

http://slidepdf.com/reader/full/how-to-conduct-rbi-assessment-of-gas-heater-untuk-lingkungan-sendiri 1/17

of 17

Exhibit D

To Professional Services Agreement No. CO.1507 dated 10 August 2004

Risk Based Inspection6 MMBTU Gas Heater - North Duri Cogen

PT. Mandau Cipta Tenaga Nusantara



of 17

CONTENT

1 SCOPE

1.1 Project description1.2 Reference1.3 Job Organization

2 DISMANTLE, CLEANING AND RE-INSTALL

3 INSPECTION AND VERIFICATION

3.1 Shell3.2 Fire Tube3.3 Tube Bundle3.4 Expansion Tank

3.5 Piping

4 RISK ASSESSMENT

4.1 Data and Information Collection4.2 Identifying Deterioration Mechanisms and Failure Modes4.3 Assessing Probability of Failure4.4 Assessing Consequence of Failure4.5 Risk Determination, Assessment and Management4.6 Risk Management with Inspection Activities4.7 Other Risk Mitigation Activities

5 DELIVERABLES

6 COMMUNICATIONS

7 SCHEDULE

8 EQUIPMENT



of 17

1 INTRODUCTION

1.1 Project Description

This project coordination procedure describes the activities performed by PT. GL Nusantara for RiskBased Inspection of 6 MMBTU Gas Heater of PT. Mandau Cipta Tenaga Nusantara (MCTN).

The brief scope of work will be as the following :

DISMANTLE, CLEANING AND RE-INSTALL

INSPECTION AND VERIFICATION9 Shell9 Fire Tube9 Tube Bundle9 Expansion Tank

9 Piping

SAMPLING OF WATER + DEPOSIT and LABORATORY TESTING

RISK ASSESSMENT9 Data and Information Collection9 Identifying Deterioration Mechanisms and Failure Modes9 Assessing Probability of Failure9 Assessing Consequence of Failure9 Risk Determination, Assessment and Management9 Risk Management with Inspection Activities

1.2 Reference

Invitation to Bid No. 14/P/VI/2004 MCTN Bid Proposal PT. GL Nusantara API 510 – Pressure Vessel Inspection Code : Maintenance Inspection, Rating, Repair and

Alteration API 570 – Piping Inspection Code : Inspection, Repair, Alteration and Rerating of In-

Service Piping Systems API 572 - Inspection of Pressure Vessels (Towers, Drums, Reactors, Heat Exchangers,

and Condensers) API 579 – Fitness for Service API 580 – Risk based Inspection API 581 – Risk based Inspection Base Resource Document



of 17

1.3 Job Organization

The Project Team as shown in the above figure is composed of experienced engineers familiar with thework areas they are representing. Each team member knows the scope of the project and is dedicatedto contribute to its successful completion. Separate internal project and familiarisation meetings will beheld throughout the project period.

PT. Germanischer Lloyd – Nusantara

Wisma Barito Pasific 3rd Floor Jl. Letjen S Parman Kav. 62-63

Jakarta 11410, IndonesiaPhone : + 62 21 5367 9201

Fax : + 62 21 5367 9202

Project Coordinator Hermas Kornelius, ST

RBI Engineer Ir. Dwi Priyanta, MSE

Mechanical / Process Engineer Ir. Negari Karunia Adi

Materials & Corrosion SpecialistDr. Ir. Johny Wahyuadi, DEA

QB Johnson RepresentativeMichael W Kort, ME

Technical Advisor Gareth Thomas

Germanischer Lloyd GLM Sdn Bhd

Technical Office South East Asia3rd floor West Block

Wisma Selangor Dredging142, Jalan Ampang

50450 Kuala Lumpur, Malaysia

PT. Gasuma CorporindoZulfikar Joesoef



of 17

Roles and Responsibilities

PT. GL Nusantara (GLN) is responsible for managing the contract and the overall contract performancefor Risk Based Inspection of (RBI) of Gas Heater at North Duri Cogen. GLN will provide qualified andexperience personnel, facilities and supervision as specified in the contract no. ………….

Germanischer Lloyd GLM Sdn Bhd will provide technical assistance for PT. GL Nusantara for regardingall technical aspects in the RBI scope of work.

QB Johnson Representative (QBJ) is responsible for technical assistance and supervision duringopening, cleaning, closing and commissioning of gas heater.

PT. Gasuma Corporindo (Gasuma) as sole agent of QB Johnson is responsible for opening, cleaningand closing of gas heater. Gasuma will provide all necessary equipment and manpower required for thework.



of 17

2 DISMANTLE, CLEANING AND RE-INSTALL

MCTN is responsible to provide safe working environment prior to commence the works by isolating theequipment from the main process system. All personnel involved in these tasks shall follow the safetyrequirements of MCTN. During dismantle, cleaning and reinstall tasks, MCTN will accompany and

supervise the work as per MCTN safety requirements.

Dismantle re-install of flare stack and fire tube; and cleaning of internal shell before inspectionperformed will be responsible of QBJ and Gasuma. This work shall be done between 2 days (48 hours)to minimize effect to other related equipment.

The brief tasks for dismantle, cleaning and re-install are :

Preparation and safety (proper clothing, safety shoes, hard hat, gloves, safety glasses, rubber jacket, rubber pant, rubber gloves, rubber boot, face mask, respirator, etc)

Shut down the heater Drain glycol, capacity about 10,000 gallons

Remove flare stack Remove fire tube, weight 1.6 MT Cleaning by water jet Ready for internal inspection through opening of 44”x21” Re-install fire tube after inspection Re-install stack Re-install fire box Final check : bolt, electrical, all tools shall be accounted Replenishment : close the drain, remove temporary line, replenish the vessel 50% glycol + 50%

water. Commissioning



of 17

3 INSPECTION AND VERIFICATION

PT. GL Nusantara will perform detailed inspection during and after dismantling of the gas heater tocollect all data and information related to deterioration mechanism. These activities will follow by dataverification / interview with the operators related to the consequences of equipment failure.

The detailed inspection techniques and locations for each equipment part are described as thefollowing :

3.1 Shell

Examine the surfaces of shells and heads carefully for possible cracks, blisters, bulges, andother signs of deterioration. Pay particular attention to the skirt and to support-attachment and

knuckle regions of the heads. If evidence of distortion is found, it may be necessary to make adetailed check of the actual contours or principal dimensions of the vessel and to comparethose contours and dimensions with the original design details.

Examine the surfaces of all manways, nozzles, and other openings for distortion, cracks, andother defects, paying particular attention to the welding used to attach the parts and their reinforcements.

Examine accessible flange faces for distortion and determine the condition of gasket-seatingsurfaces in the vicinity of the corroded area.

Corrosion under insulation (CUI) - close visual inspection, with attention to :9 damaged metallic cladding;9 gaps or unsealed joints;9 leaks or spills;9 rusted area;9 Breaks/shrinkage cracks in weather and vapour barriers; and9 Identify critical areas: branches, supports, hangers, drains, sample points, etc.

External – corrosion under insulation (CUI)

Internal – general corrosion



of 17

UT Scanning 4” x 100” on closure (vertical) Internal visual inspection, pits depth measurement; and UT spot thickness.

The external inspection and UT scanning on closure will be performing during draining the glycol.

3.2 Fire Tube

Visual Inspection, pits depth measurement Strapping measurement and UT thickness with locations as shown by arrow.

The fire tube inspection will be performing during draining or cleaning the gas heater.

3.3 Tube Bundle

Tube bundle is susceptible to external and internal corrosion (general and localized). This corrosion canbe detected by UT scanning and spot thickness.

UT scanning on the U-turn UT spot thickness every 1 foot at 4 points

3.4 Expansion Tank

Expansion tank is susceptible to external CUI and internal corrosion (general and localized). Theinternal corrosion can be detected by UT scanning on the both side end of tank.

Corrosion under insulation (CUI) - close visual inspection, with attention to :9 damaged metallic cladding;9 gaps or unsealed joints;9 leaks or spills;

External corrosionCreep, Carburization

UT scanning 4” x 20”(vertical)



of 17

9 rusted area;9 Breaks/shrinkage cracks in weather and vapour barriers; and9 Identify critical areas: branches, supports, hangers, drains, sample points, etc.

The expansion tank inspection will be performing during draining or cleaning the gas heater.

3.5 Piping

External visual Inspection for Piping : Leaks. Misalignment (piping misalignment/restricted movement, expansion joint misalignment) Vibration (inadequate support, threaded connections, loose supports causing metal wear) Supports (shoes off support, hanger distortion or breakage, brace distortion/breakage, loose

brackets, slide plates/rollers, support corrosion) Corrosion (bolting support points under clamps, coating/painting deterioration)

UT Scanning on the elbow / pipe bend Spot thickness (8 points) every 1 foot.

The piping inspection will be performing during draining or cleaning the gas heater.



of 17

4 RISK ASSESSMENT

4.1 Data and Information Collection

MCTN will supply data and information needed for a RBI analysis as follows :

Basis Design Design philosophy P&ID and PFD Process description Design data & calculation List of equipment, piping and valves Fabrication and manufacturing drawings Equipment and piping specifications Process fluid compositions Process / utility contaminants Inspection, repair and replacement records

Operating conditions Failure data Safety systems Detection systems HAZOP report Risk assessment studies Safety critical elements Performance standards Coating, cladding and insulation data Business interruption cost Equipment replacement costs

The above data is expected to receive by PT. GL Nusantara one week before starting the inspectionand verification as described in section 2 and 3 of this procedure.

In case that data are not available, PT GL Nusantara will perform other approach such as byinterviewing MCTN operator and maintenance personnel, etc.

4.2 Identifying Deterioration Mechanisms and Failure Modes

Identification of the appropriate deterioration mechanisms, susceptibilities and failure modes for allequipment included in a RBI study is essential to the quality and the effectiveness of the RBI evaluation

The term failure can be defined as termination of the ability to perform a required function. RBI isconcerned with loss of containment failures caused by deterioration.

The term deterioration mechanism is defined as the type of deterioration that could lead to a loss of containment. There are four major deterioration mechanisms observed in the hydrocarbon andchemical process industry:

Thinning (includes internal and external)



of 17

Stress Corrosion Cracking Metallurgical and Environmental Mechanical

4.3 Assessing Probability of Failure

The probability analysis in a RBI program is performed to estimate the probability of a specific adverseconsequence resulting from a loss of containment that occurs due to a deterioration mechanism(s). Theprobability that a specific consequence will occur is the product of the probability of failure (POF) and theprobability of the scenario under consideration assuming that the failure has occurred.

The probability of failure analysis should address all deterioration mechanisms to which the equipmentbeing studied is susceptible. Further, it should address the situation where equipment is susceptible tomultiple deterioration mechanisms (e.g. thinning and creep). The analysis should be credible andrepeatable.

It should be noted that deterioration mechanisms are not the only causes of loss of containment. Other causes of loss of containment could include but are not limited to:

Overpressure due to pressure relief device failure Operator error

These and other causes of loss of containment may have an impact on the probability of failure and maybe included in the probability of failure analysis.

Regardless of whether a qualitative or a quantitative analysis is used, the probability of failure isdetermined by two main considerations:

• Deterioration mechanisms and rates of the equipment item's material of construction, resulting fromits operating environment.

• Effectiveness of the facility's inspection program to identify and monitor the operative deteriorationmechanisms so that the equipment can be taken out of service prior to failure.

4.4 Assessing Consequence of Failure

Loss of containment implies a breach of the pressure boundary, and may be the result of a failure of apressure containing component or a sealing element. The consequence of loss of containment isgenerally evaluated as loss of fluid to the atmosphere. The consequence effects for loss of containmentcan be generally considered in the following categories:

Safety and health impact Environmental impact Production losses Maintenance costs

RBI is mainly concerned with loss of containment failures. Other functional failures could be included ina RBI study such as :

Functional or mechanical failure of internal components of pressure containing equipment



of 17

Gas heater tube failure Pressure relief device failure

Quantitative Consequences Analysis

A quantitative method involves using a logic model depicting combinations of events to represent theeffects of failure on people, property, the business and the environment. Quantitative models usuallycontain one or more standard failure scenarios or outcomes and calculate consequence of failurebased on:

Type of process fluid in equipment State of the process fluid inside the equipment (solid, liquid or gas) Key properties of process fluid (molecular weight, boiling point, autoignition, density, etc.) Process operating variables such as temperature and pressure Mass of inventory available for release in the event of a leak Failure mode and resulting leak size State of fluid after release in ambient conditions (solid, gas or liquid)

4.5 Risk Determination, Assessment and Management

Once the probabilities of failure and failure mode or modes have been determined for eachdeterioration mechanism, the probability of each credible consequence scenario can be determined. Inother words, the loss of containment failure may only be the first event in a series of events that leadsto a specific consequence. The probability of each event leading up to the specific consequence needsto be factored into the probability of the specific consequence occurring.

It is important to understand this linkage between the probability of failure and the probability of possibleresulting incidents. The probability of a specific consequence is tied to the severity of the consequenceand may differ considerably from the probability of equipment failure itself. Probabilities of incidentsgenerally decrease with the severity of the incident.

Calculate Risk

Referring back to the Risk equation:

Risk = Probability X Consequence

It is now possible to calculate the risk for each specific consequence. The risk equation can now bestated as:

Risk of a specific consequence = (Probability of a specific consequence) X(Specific Consequence)

Risk Presentation

Once risk values are developed, they can then be presented in a variety of ways to communicate theresults of the analysis to decision-makers and inspection planners. One goal of the risk analysis is to



of 17

communicate the results in a common format that a variety of people can understand. Using a riskmatrix or plot is helpful in accomplishing this goal.

1 2 3 4 5Consequence Category

P r o b a b i l i t y C a t e g o r y

A

B

C

D

E

Qualitative Risk Matrix

Medium Risk

High Risk

Low Risk

P

R

O

B

A

B

I

L

I

T

Y

O

F

F

A

IL

U

R E

Iso-Risk Line

1 2

3

6

5

7

4

10

9

8

CONSEQUENCE OF FAILURE

Risk Plot

Risk Management

Based on the ranking of items and the risk threshold, the risk management process begins. For risksthat are judged acceptable, no mitigation may be required and no further action necessary.

For risks considered unacceptable and therefore requiring risk treatment, there are various mitigationcategories that should be evaluated:

• Inspection/Condition Monitoring: can a cost-effective inspection program, with repair as indicatedby the inspection results, be implemented that will reduce risks to an acceptable level?

• Consequence mitigation: can actions be taken to lessen the consequences related to an equipmentfailure?

• Probability mitigation: can actions be taken to lessen the probability of failure such as metallurgychanges or equipment redesign?



of 17

4.6 Risk Management with Inspection Activities

In previous sections, it has been mentioned that risk can be reduced by inspection. Obviously,inspection does not arrest or mitigate deterioration mechanisms. Inspection serves to identify, monitor,and measure the deterioration mechanism(s). Also, it is invaluable input in the prediction of when the

deterioration rate will reach a critical point. Correct application of inspections will improve the user'sability to predict the deterioration mechanisms and rates of deterioration. The better the predictability,the less uncertainty there will be as to when a failure will occur. Mitigation (repair, replacement etc.) canthen be planned and undertaken prior to the predicted failure date. The reduction in uncertainty andincrease in predictability through inspection translate directly into a reduction in the probability of afailure and therefore a reduction in the risk. Inspection is usually a cost-effective method of affectingrisk reduction.

Once a RBI assessment has been completed, the items with higher or unacceptable risk should beassessed for potential risk reduction through inspection. Whether inspections will be effective or not willdepend on:

Equipment type Active and potential deterioration mechanism(s) Rate of deterioration or susceptibility Inspection methods, coverage and frequency Accessibility to expected deterioration areas Shutdown requirements

Inspection is only effective if the inspection technique chosen is sufficient for detecting the deteriorationmechanism and its severity. As an example, spot thickness readings on a piping circuit would beconsidered to have little or no benefit if the deterioration mechanism results in local pitting. In this case,ultrasonic scanning and radiography will be more effective. The level of risk reduction achieved byinspection will depend on:

Mode of failure of the deterioration mechanism Time interval between the onset of deterioration and failure Detection capability of inspection technique Scope of inspection Frequency of inspection

Inspection costs can be more effectively managed through the utilization of RBI. Resources can beapplied or shifted to those areas identified as a higher risk or targeted based on the strategy selected.Consequently this same strategy allows consideration for reduction of inspection activities in thoseareas that have a lower risk or where the inspection activity has little or no affect on the associated

risks. This results in inspection resources being applied where they are needed most.

4.7 Other Risk Mitigation Activities

As described in the previous section, inspection is often an effective method of risk mitigation. However,inspection may not always provide sufficient risk mitigation or may not be the most cost effectivemethod. The purpose of this section is to describe other methods of risk mitigation.



of 17

Equipment Replacement and Repair

When equipment deterioration has reached a point that the risk of failure cannot be managed to anacceptable level, replacement/repair is often the only way to mitigate the risk.

Evaluating Flaws for Fitness for Service

The RBI analysis may identify equipment that is of sufficiently high risk that repair/replacement isrecommended. A Fitness for Service assessment may be done to determine if the equipment maycontinue to be safely operated and under what conditions.

Equipment Modification, Redesign and Rerating

Modification and redesign of equipment can provide mitigation of probability of failure. Examplesinclude:

Change of metallurgy Addition of linings Addition of corrosion protection

Removal of deadlegs

5 DELIVERABLES

PT. GL Nusantara will provide FINAL REPORT to MCTN with “6 MMBTU Gas Heater – RBI StrategyDocument” which shall cover but not limited to :

Identification of damage mechanism for each equipment item and piping element Assumption listing Likelihood of failure assessment and identify driver(s) Consequence of failure assessment and identify driver(s) Risk ranking (matrix or plot) Recommended inspection program Recommendation for further detail consequence analysis or consequence mitigation measures

PT. GL Nusantara will provide “Inspection Work Pack” for pressure containment including followinginformation :

Marked up isometric drawings with inspection points Detailed NDT procedures

PT. GL Nusantara will provide recommendations on inspection Management System and organizationincluding roles and responsibility.

PT. GL Nusantara will present the draft of Final Report at North Duri Cogen by the RBI Team includingfrom GL Malaysia.



of 17

6 COMMUNICATIONS

6.1 PT. GL Nusantara (GLN)

Contact person : Hermas Kornelius Address : Wisma Barito Pasific 3rd Floor

Jl. S Parman Kav. 62-63Jakarta 11410, Indonesia

Phone : +62 21 5367 9201Fax : +62 21 5367 9202Mobile : +62 0888 188 6205email [email protected]

6.2 QB Johnson Representative (QBJ)

Contact person : Michael W Kort,

Phone : +62 21 737 2847Mobile : +62 0812 888 5459email [email protected]

6.3 PT. Gasuma Corporindo (Gasuma)

Contact person : Zulfikar Joesoef Address : Pondok Pinang Centre A-4

Jl. Ciputat Raya – Pondok PinangJakarta 12310, Indonesia

Phone : +62 21 765 8746, 769 2401Fax : +62 21 750 9510Mobile : +62 0812 918 3574Email: [email protected]

6.4 MCTN / Amoseas Indonesia

Contact person : Irwan Januar Address : North Duri Cogeneration Plant

Duri Field Area 11Drui – Pekanbaru

Phone : + 62 765 99 5610Fax : + 62 765 99 7818Mobile : + 62 0812 750 4025email [email protected]

Contact person : Twi Sevon Rumdy Address : Gedung Sarana Jaya,

Jl. Budi Kemuliaan I - No 1Jakarta 10110, Indonesia

Phone : + 62 21 343 53306Fax : + 62 21 385 1829Mobile : + 62 0813 152 36195



of 17

email [email protected]

7 SCHEDULE

No Description Date Parties Involved

1 Review documents supply by MCTN 9-13 Aug 2004 GLN

2 Site visit North Duri Cogen 16 Aug 2004 QBJ + GLN

3 Submit detailed execution plan 18 Aug 2004 QBJ + GLN

4 Discussion of detail execution plan 19 Aug 2004 QBJ + GLN + MCTN

5 Mob – demob personnel, equipment 21-22 Aug 2004 QBJ/Gasuma + GLN

6 Final preparation 23 Aug 2004 QBJ

7 Isolation of equipment 24 Aug 2004 MCTN and QBJ/Gasuma

8 Drain and dismantle 24 Aug 2004 QBJ/Gasuma - Day shift

9 Cleaning 24 Aug 2004 QBJ/Gasuma - Night shift

10 Inspection 25 Aug 2004 GLN - Day shift

11 Reinstallation 25 Aug 2004 QBJ/Gasuma - Day shift

12 Replenish 50% glycol + 50% water 25 Aug 2004 QBJ/Gasuma - Night shift13 Commissioning 25 Aug 2004 QBJ and MCTN -Night shift

14 Risk assessment 26 Aug – 6 Sep 2004 GLN and MCTN

15 Draft report finish 7 Sep 2004 GLN

16 Presentation to MCTN 9 Sep 2004 GLN and MCTN

17 Revise report as per MCTN comments 13-15 Sep 2004 GLN

18 Submit final report to MCTN 16 Sep 2004 GLN

8 EQUIPMENT

Gasuma shall provide, but not limited to, the necessary and suitable equipment for dismantle, cleaningand re-install tasks as the following :

Pumps and hose Truck crane High pressure washer Water tank Hand tools PPE, including for confined space Gas detector Blower Low voltage lighting Gaskets Consumable materials, etc

how to conduct rbi assessment of gas heater - untuk lingkungan sendiri

Documents