COMMISSIONING GENERAL GUIDELINES
COMMISSIONING GENERAL GUIDELINES
COMMISSIONING GENERAL GUIDELINES
1.0 INTRODUCTION
This write up is based on my working experience in commissioning with a leading engineering consulting firm . Commissioning though the last activity but is equally important for a new project. This is the last opportunity for the engineers to detect any left out problems during the execution of the project, correct it, and put the plant into operation for its trouble free commercial operation. This is a team work requiring full co operation, better understanding among Vendor (Supplier, Contractor ), Purchaser ( Owner ) and Consultant ( Engineer) to make it easy and achieve best result.
2.0 COMMISSIONING
Commissioning is the process of taking Plant, equipment and systems from an agreed state of erection completion through the operation of checking, start up, tuning and testing to the state of commercial operation.
It is important to avoid the impression that ‘commissioning’ is simply “putting the Plant into operation”. Any installed Plant is purchased to a specification, so it should be tested over the full range of the specification. Testing methods, procedures and techniques applied should be conducted in accordance with standard practices and applicable codes and standards
Commercial Operation shall mean the completion of a definite period full load run with all required tests fully completed. There must also be a joint agreement at Site that this state has been reached.
3.0. OBJECTIVES OF COMMISSIONING
Commissioning aims at achieving the following objectives:
3.1 Make the Plant available for commercial operation as soon as possible by preparation of the equipment and systems for reliable and trouble free operation. This may involve;
a) Inspection, pre-operational checks and preparation of the equipment for start up including specialized cleaning.
b) Trial run, initial operation, performance monitoring and proving validity of Plant operation instructions.
c) Problem analysis and solution identifying- establishing the reasons for any limitation of either performance or flexibility of operation.
3.2 Fulfilling statutory obligations and contractual requirements like demonstrating that the Plant is capable of safe and reliable operation and that it meets the design specifications and performance guarantees.
3.3 Compiling and documentation of equipment test and performance data for future reference and comparison using standard forms and procedures.
2.0 COMMISSIONING
Commissioning is the process of taking Plant, equipment and systems from an agreed state of erection completion through the operation of checking, start up, tuning and testing to the state of commercial operation.
It is important to avoid the impression that ‘commissioning’ is simply “putting the Plant into operation”. Any installed Plant is purchased to a specification, so it should be tested over the full range of the specification. Testing methods, procedures and techniques applied should be conducted in accordance with standard practices and applicable codes and standards
Commercial Operation shall mean the completion of a definite period full load run with all required tests fully completed. There must also be a joint agreement at Site that this state has been reached.
3.0. OBJECTIVES OF COMMISSIONING
Commissioning aims at achieving the following objectives:
3.1 Make the Plant available for commercial operation as soon as possible by preparation of the equipment and systems for reliable and trouble free operation. This may involve;
a) Inspection, pre-operational checks and preparation of the equipment for start up including specialized cleaning.
b) Trial run, initial operation, performance monitoring and proving validity of Plant operation instructions.
c) Problem analysis and solution identifying- establishing the reasons for any limitation of either performance or flexibility of operation.
3.2 Fulfilling statutory obligations and contractual requirements like demonstrating that the Plant is capable of safe and reliable operation and that it meets the design specifications and performance guarantees.
3.3 Compiling and documentation of equipment test and performance data for future reference and comparison using standard forms and procedures.
3.4 Training of Operation & Maintenance personnel.
4.0 BASIC STEPS IN COMMISSIONING
For the smooth commissioning of the Plant, all equipment and systems should be made ready at appropriate stages. Broadly, the activities comprising commissioning are carried out in the following steps/stages:
4.1 Planning and preparation
Planning for commissioning the Plant should start even during the early stages of contract award for the major equipment. Agreement should be reached on the procedures for the trial runs, start up, testing and on the activities like chemical cleaning, steam blowing and other commissioning activities. For effective mobilization of resources at Site and also for efficient monitoring a PERT chart or a bar chart for commissioning activities should be prepared.
4.2 Completion of Erection
This is normally considered an easily identifiable point and, when reached, implies that further activities can take place. However at Site it is not easily identified. Interpretation of “completion of erection” of even a simple item like pump/motor unit can vary considerably. Consider the following two situations:
a) Pump and Motor mechanically complete; electrical supply available from a temporary source; working fluid available through previously commissioned pipework; access poor, and
b) Pump and Motor erection mechanically complete; all labels fitted; the system is connected to permanent power supply with all protections tested; working fluid as in (a) and permanent access made ready.
It is probably fair to say that the Pump/Motor unit would operate equally well in both the situations, although with increased risk of trip and personal injury in case (a). The important point to note is that “completion of erection” must be clearly and unambiguously defined, the plant/equipment should be declared safe for operation according to the safety rules and must be cleared for commissioning by the Erection/Construction Department.
For the smooth commissioning of the Plant, all equipment and systems should be made ready at appropriate stages. Broadly, the activities comprising commissioning are carried out in the following steps/stages:
4.1 Planning and preparation
Planning for commissioning the Plant should start even during the early stages of contract award for the major equipment. Agreement should be reached on the procedures for the trial runs, start up, testing and on the activities like chemical cleaning, steam blowing and other commissioning activities. For effective mobilization of resources at Site and also for efficient monitoring a PERT chart or a bar chart for commissioning activities should be prepared.
4.2 Completion of Erection
This is normally considered an easily identifiable point and, when reached, implies that further activities can take place. However at Site it is not easily identified. Interpretation of “completion of erection” of even a simple item like pump/motor unit can vary considerably. Consider the following two situations:
a) Pump and Motor mechanically complete; electrical supply available from a temporary source; working fluid available through previously commissioned pipework; access poor, and
b) Pump and Motor erection mechanically complete; all labels fitted; the system is connected to permanent power supply with all protections tested; working fluid as in (a) and permanent access made ready.
It is probably fair to say that the Pump/Motor unit would operate equally well in both the situations, although with increased risk of trip and personal injury in case (a). The important point to note is that “completion of erection” must be clearly and unambiguously defined, the plant/equipment should be declared safe for operation according to the safety rules and must be cleared for commissioning by the Erection/Construction Department.
4.3 Pre-commissioning, Inspection Checks, establishing cleanliness
The first important commissioning activity at Site is Plant walk downs and the inspection and checking of equipment, before attempting to put them into service. This activity is meant to ensure erection completion, compliance of critical dimensions, tolerances, manual operation of equipment such as valves, dampers etc, to check physical free movement, operation of limit switches etc., removal of unwanted material and access facilities for maintenance and inspection. These checks should be specified in the associated commissioning check list documents. Various equipment pipework, pressure vessels etc. arriving at Site would require degreasing, application of protective coating, flushing of pipelines etc. These procedures must be clearly outlined and carried out.
4.4 Admission of working fluid
The term “fluid” here is used in a wide context. It can mean gas, steam, oil, water, air or electricity. This stage implies that the equipment has had all checks carried out to a state where it is considered safe to admit the working fluid.
It is important to consider the following points;
What is the source of working fluid and how is it controlled?
What are the implications of the working fluid if, a) everything is normal, and b) if circumstances are abnormal?
How much do we monitor the admission of the working fluid to detect abnormalities?
Time spent in considering the above is well spent because it can prevent major incidents on account of minor lapses.
4.5 Application of safety rules
All equipment must be covered by the existing safety rules before it is energized or the working fluid is admitted for the first time. The Constructors usually view the imposition of safety rules as a hindrance to their progress, but adherence to safety rules is very important and they should be strictly enforced.
The first important commissioning activity at Site is Plant walk downs and the inspection and checking of equipment, before attempting to put them into service. This activity is meant to ensure erection completion, compliance of critical dimensions, tolerances, manual operation of equipment such as valves, dampers etc, to check physical free movement, operation of limit switches etc., removal of unwanted material and access facilities for maintenance and inspection. These checks should be specified in the associated commissioning check list documents. Various equipment pipework, pressure vessels etc. arriving at Site would require degreasing, application of protective coating, flushing of pipelines etc. These procedures must be clearly outlined and carried out.
4.4 Admission of working fluid
The term “fluid” here is used in a wide context. It can mean gas, steam, oil, water, air or electricity. This stage implies that the equipment has had all checks carried out to a state where it is considered safe to admit the working fluid.
It is important to consider the following points;
What is the source of working fluid and how is it controlled?
What are the implications of the working fluid if, a) everything is normal, and b) if circumstances are abnormal?
How much do we monitor the admission of the working fluid to detect abnormalities?
Time spent in considering the above is well spent because it can prevent major incidents on account of minor lapses.
4.5 Application of safety rules
All equipment must be covered by the existing safety rules before it is energized or the working fluid is admitted for the first time. The Constructors usually view the imposition of safety rules as a hindrance to their progress, but adherence to safety rules is very important and they should be strictly enforced.
4.6 Using the Plant’s Operation Personnel
The Plant’s Operation Personnel are used as much as possible during start up and commissioning, including the use of Plant Operators to energize permanent plant equipment. Subsequent to start up, testing and commissioning of the systems they will be turned over to the Plant’s O & M Personnel who will then be responsible for routine O & M. The Plant’s O&M Management is to be provided with a commissioning plan and schedule. Recognizing the importance of communication and interface with various Plant entities for the safe and efficient start up, Commissioning Engineers should notify the Control Room and the Plant’s Operating Personnel of ongoing commissioning activities on a regular basis.
4.7 Trial Run and Initial Operation
This activity normally takes place after the equipment has come under the safety rules and is witnessed by all interested parties.
It is important before this stage is reached to have agreed under what circumstances initial operation will take place. Compromises have to be reached on what is essential and what is desirable. It is therefore important to decide which items are essential and the Plant/equipment will not be run under any circumstances unless the requirements for these items are met. Often this tends to be a pressure area when Constructors can see that the Plant is almost ready to run and is only being held up for seemingly small items like say, alarms, indicators etc.
Wherever possible all rotating equipment must be individually trial run. Before the trial run, service facilities like, power, cooling water, lubricants etc., must be made available. Prior to trial run the drive unit (usually an electric motor) should be trial run in the uncoupled condition after carrying out the commissioning checks specified for that particular equipment. After successful completion of trial run of the drive, the equipment should be coupled and trial run for about eight (8) hours.
During the trial run the equipment should be carefully observed for any unusual noise, abnormal vibration or undue bearing temperature rise. Any defects should be immediately attended and trial run repeated till satisfactory results are obtained.
A record of trial run/initial operation including the vibration readings, bearing temperature rise, starting current, no load current, time for acceleration/deceleration, defects noticed, rectifications carried out etc., should be maintained for future reference.
4.8 System Checks and setting of parameters for operation regimes
The Plant’s Operation Personnel are used as much as possible during start up and commissioning, including the use of Plant Operators to energize permanent plant equipment. Subsequent to start up, testing and commissioning of the systems they will be turned over to the Plant’s O & M Personnel who will then be responsible for routine O & M. The Plant’s O&M Management is to be provided with a commissioning plan and schedule. Recognizing the importance of communication and interface with various Plant entities for the safe and efficient start up, Commissioning Engineers should notify the Control Room and the Plant’s Operating Personnel of ongoing commissioning activities on a regular basis.
4.7 Trial Run and Initial Operation
This activity normally takes place after the equipment has come under the safety rules and is witnessed by all interested parties.
It is important before this stage is reached to have agreed under what circumstances initial operation will take place. Compromises have to be reached on what is essential and what is desirable. It is therefore important to decide which items are essential and the Plant/equipment will not be run under any circumstances unless the requirements for these items are met. Often this tends to be a pressure area when Constructors can see that the Plant is almost ready to run and is only being held up for seemingly small items like say, alarms, indicators etc.
Wherever possible all rotating equipment must be individually trial run. Before the trial run, service facilities like, power, cooling water, lubricants etc., must be made available. Prior to trial run the drive unit (usually an electric motor) should be trial run in the uncoupled condition after carrying out the commissioning checks specified for that particular equipment. After successful completion of trial run of the drive, the equipment should be coupled and trial run for about eight (8) hours.
During the trial run the equipment should be carefully observed for any unusual noise, abnormal vibration or undue bearing temperature rise. Any defects should be immediately attended and trial run repeated till satisfactory results are obtained.
A record of trial run/initial operation including the vibration readings, bearing temperature rise, starting current, no load current, time for acceleration/deceleration, defects noticed, rectifications carried out etc., should be maintained for future reference.
4.8 System Checks and setting of parameters for operation regimes
When a system or sub-system has completed its initial operation, it then has to be checked for correct response to operational parameters, circumstances and that it follows the established operation regime (eg. protections, interlocks, permissives, auto start etc.) Sometimes it may be necessary to simulate inputs to test the response of the system. Frequently a system is part of much larger system, then as other parts of the overall system become available simulated checks are replaced by line checks. After these checks are carried out the system should be adjusted and set to operate as per the established regimes.
4.9 Performance Testing
The decision as to whether the Plant meets its major contractual and design criteria is taken on the results of Performance Tests on the major equipment and systems of the Plant. These are well defined in standard test codes and it is only necessary to agree to the logistics of carrying out such tests. It is important to carry out the tests strictly as per the agreed test codes to avoid any chances of a repeat test following any debate.
The decision as to whether the Plant meets its major contractual and design criteria is taken on the results of Performance Tests on the major equipment and systems of the Plant. These are well defined in standard test codes and it is only necessary to agree to the logistics of carrying out such tests. It is important to carry out the tests strictly as per the agreed test codes to avoid any chances of a repeat test following any debate.
4.10 Training of Plant Operation & Maintenance Personnel
This is the last stage of the commissioning process. Since the Plant’s O & M Personnel are kept involved from the very beginning of commissioning activities it enables them to get familiar with the Plant and equipment specific operating procedures. The Commissioning Engineer at Site should suitably instruct the operating personnel on the operations involved in bringing new equipment to the full operation mode. Important operational safeguards and procedures should be highlighted and explained.
This is the last stage of the commissioning process. Since the Plant’s O & M Personnel are kept involved from the very beginning of commissioning activities it enables them to get familiar with the Plant and equipment specific operating procedures. The Commissioning Engineer at Site should suitably instruct the operating personnel on the operations involved in bringing new equipment to the full operation mode. Important operational safeguards and procedures should be highlighted and explained.
5.0 GENERAL COMMISSIONING GUIDELINES
a) All plant and equipment must be clearly identified with its agreed title/tag.
b) Lighting must be adequate to promote a safe working environment.
c) Safe access to and around the equipment being commissioned must be maintained at all times. Clearly identified escape routes should be provided.
d) Access to be restricted to personnel necessarily involved with commissioning. Temporary barriers may be required to inhibit access to unauthorized personnel.
e) Permanent fire protection equipment should be in service, augmented by additional staff and/or temporary fire extinguishers wherever necessary.
f) Plant being commissioned should be clearly marked with durable, easily noticed, self adhesive labels to warn personnel of equipment/systems which are about to start up and also of which section of the plant are subject to safety rules.
a) All plant and equipment must be clearly identified with its agreed title/tag.
b) Lighting must be adequate to promote a safe working environment.
c) Safe access to and around the equipment being commissioned must be maintained at all times. Clearly identified escape routes should be provided.
d) Access to be restricted to personnel necessarily involved with commissioning. Temporary barriers may be required to inhibit access to unauthorized personnel.
e) Permanent fire protection equipment should be in service, augmented by additional staff and/or temporary fire extinguishers wherever necessary.
f) Plant being commissioned should be clearly marked with durable, easily noticed, self adhesive labels to warn personnel of equipment/systems which are about to start up and also of which section of the plant are subject to safety rules.
6.0 PLANT TURNOVER/TAKING OVER BY THE OWNER
After successful commissioning of Plant, equipment and systems and prior to turning the Plant over to the Owner, the Commissioning Engineer should participate in a walk down with the Owner of the Plant. Acknowledged deficient items will be corrected or added to the Project ‘punch list’ for completion after turnover to the Owner. Standard project turnover/taking over documentation and procedures should be used.
After successful commissioning of Plant, equipment and systems and prior to turning the Plant over to the Owner, the Commissioning Engineer should participate in a walk down with the Owner of the Plant. Acknowledged deficient items will be corrected or added to the Project ‘punch list’ for completion after turnover to the Owner. Standard project turnover/taking over documentation and procedures should be used.
Good, Thanks For your Help Sir
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