Inspection – Preparation

Here are some guidelines on preparing prior to inspection mainly those engineers are considered young engineers. Experienced engineer would know what to be asked or recorded during the inspection and obviously know what to prepare prior to inspection visit in site.

An engineer need to know what the equipment to be inspected obviously and any related documents to the equipments need to be brought. This is crucial because to have some understanding of the inspection process. One of the main documents that need to be brought while in site is obviously are drawings. Drawings like process flow diagram, (PFD), piping and instrumentation diagram, (P&ID), isometric drawing, and assembly drawing are really important while conducting inspection. This is because of the identity of the equipments, layouts, etc are provided in drawings. So, it would give the some idea on the internals of the equipment such as baffles, wire-meshed, inlet device, etc.

Sometime most of the preparations are done perfectly but still sometime there is a circumstance where the major license that need to have forgotten to take which is confined space entry permit. This sometime would cause unnecessary delay to overall project deliverables. This mainly happens for those had conducted any inspection during last turn-around and thought that there’s still valid but unfortunately it is already expired. So, it is advisable to cover this requirement as a part of checklist and put it as first priority.

Inspection

Inspection can be done for two main reasons; first for periodic check-up as human being is recommended to do medical check-up and second if there is any rectification to be done to the system as human being as well where need to go for medication.

The inspection wills actually reflecting the performance of the plant or platform in term of downtime. As for shutdown, there are planned and unplanned shutdowns. So, during the planned shutdown there will be couple of teams conducting inspection for identified equipment for respective department. Obviously department such operation, technical service, maintenance, and inspection will take part as main role player. Inspection during planned shutdown usually will be taken part by almost all of the engineers from respective department. Unplanned shutdown usually occur due plant upset where unexpected than planned happens. So, the team for the inspection will be called usually as root cause analysis, (RCA) team. For this kind of inspection, usually there will be one engineer from each department.

Inspection for planned shutdown usually will take place as mandatory for Department of Occupational, Safety, and Health (DOSH) requirement to conduct inspection during the turnaround (TA). During this period of duration, related vendors also take part to inspect. As an owner of the plant, all the observations and findings will be recorded to investigate the process behavior. Normally technical service department will do all this since most of the troubleshooting will be done by this department which acts as internal consultant for the plant. The rest of the departments might look into the findings mainly on the physical of the equipments in term of the welding, joint between connection, thickness of the wall of the equipment, etc. From all the findings, respective departments will come with the recommendations or conclusions in order to rectify it before the equipment is boxed up. For example, inspection to the shell and tube heat exchanger might be found with slurry that stagnant at any corner of tube or shell. Prior to this inspection, operation/production department might have faced problem in achieving desired temperature due to inefficient heat transfer. So, further study will be conducted so that fouling in future can be reduced so that won’t affect the performance until the next turnaround. The heat exchanger might be redesigned so that minimum velocity can be achieved so that the liquid can form turbulence enough to move any possible materials along the tube or shell. Besides, for those young engineers that desired to be design engineer can be credit since have seen the real internal part of the equipments. From there, the young engineers can take some reasonable margin or consideration when designing the equipments even not highlighted by theory.

Inspection during unplanned shutdown will be conducted in order to rectify the problem faced that causes plant upset. The RCA team will conduct a study on factors and solutions and present it to the management whereby there is no presentation to the management during inspection for planned shutdown. There will be a leader selected by plant general manager to lead the study which usually from technical division that familiar with the process involved. Historical data for the operation will be studied whether the operation follows the operating envelope while operating the plant. Typical cases for this unplanned shutdown and inspection are tube ruptures for furnace and heat exchangers.So, both inspections are really crucial for all generally and those young design engineer specifically since the real equipment can be seen in term of physical appearance and problems faced. If there is any chance to get involve, then it is recommended to grab the opportunity. It might be harshly and messy but will be end up with fruitful experience and knowledge when designing any equipments.

BEM and IEM

Engineers practicing (Malaysia) engineering must register with Board of Engineers, Malaysia (BEM) in order to acknowledge their experience when certifying the engineers to be professional engineer. The number or years acknowledged by BEM is the year started from the date registered with them. In order to certify an engineer as professional engineer, the engineer must have at least three years experience (acknowledged by BEM).

People might wonder if BEM is the one giving certification for professional engineer, what goes with Institutions of Engineers, Malaysia (IEM). So, the main difference between these two is that IEM is learning organization for engineers. In order to get privileges from IEM, an engineer need to register to be member first and there are a lot of membership types. Engineers need to register to be graduate member to start getting privileges in term of trainings, industry exposure, etc. Differ from BEM, IEM recognize experience from the graduation date.

In order to upgrade the membership from graduate member to member, the engineer needs to practice engineering work which consists of design, site, project management, etc for at least three years. The work was done by the engineer must be supervised by an engineer that member of IEM (MIEM). So, this supervision can go in two different ways; direct supervision if the engineer (MIEM) and graduate engineer in one organization and indirect supervision by mentoring scheme or log book scheme. After practicing minimum three years of working experience from the date of graduation, the graduate engineer can apply for professional interview (PI) in order to upgrade the membership to MIEM. Then, engineer with MIEM can apply for professional engineer with BEM if the number of years experience meeting minimum three years requirement.

RAM Study

Reliability, availability, and maintainability (RAM) study is a method or approach that being used in many industries many years ago. This is mainly because to optimize the reliability of the system so that can reduce the downtime of the system which eventually causing loss of production. So, by conducting this RAM study operation people will aware of the availability of the equipments respect to the system and maintenance team is aware with maintenance job need to be done. This RAM study is important so that the system reliability is reliable enough to produce the products as in agreement with customer.

There are lot of software are offered in market nowadays that claim can deliver the RAM study with minimal time consumption. However, there are skills needed when developing model for the RAM study. The model usually will be modeled with reliability block diagram (RBD) or fault tree diagram and the approach or basis of both diagrams are really dependent of the engineer develop it. Both diagrams will be modeled by referring to the process flow diagram to demonstrate the continuity of the process. However, it is more recommended to develop RBD which will give more information as a result and definitely need more info to key in when developing the model.

This RAM study usually will be done in a workshop where all personnel will be in during the session. If anyone realize this session almost like hazard and operability (HAZOP) study. So, those attended or conducted the HAZOP study might realize that if the leader/chairman prepared some draft of the node to be studied would be easier to carry the HAZOP workshop. Otherwise the session would be lengthy if the node to be identified during the workshop and there will be a lot of conflicts among participants. So, it is recommend as RAM workshop leader to construct the model prior to workshop and during the session all the information will be added as the workshop goes on.

In order to be leader/chairman for the RAM workshop, he or she needs to attend couple of RAM workshop as HAZOP chairman needs to be really experienced personnel. This is because the leader should know how to raise the issue related to any systems or equipments. Similar to HAZOP study, the chairman must be able to prompt the participants to extract the information so that can be documented during the workshop.The result or conclusion is again dependent on the input that was given to the software to run it. These RAM study software will use Monte Carlos approach to simulate probabilistic statistic and will give some figure for all three; reliability, availability, and maintainability in term of probability. Normally this probability must at least more than 90% and this is even considered as bad system that having only 90% reliability, availability, or maintainability. As HAZOP, this RAM study is only method or approach to predict any contingency plan to avoid any bad downtime.

Slugging and Pigging

Slugging and pigging are normal terms commonly used in oil and gas industry, more specifically in upstream rather than downstream. This is mainly because of the different phases of fluid with presence of other materials such as sand. Because of this slugging phenomenon, there is equipment called slug catcher to catch all this nasty stuff by stabilizing the fluids from the reservoir.

In other word, this slug catcher also can be said as stabilizer (some might not agree and it depends how they interpret it) since stabilizing among oil, gas, and water until reaching certain acceptable content level.

This slugging usually takes place when there is either liquid/gas in gas/liquid when form a pocket and starts hitting the wall of the pipe. This at the end actually will shorten the life the piping and causes more frequent maintenance which actually increases the downtime of the plant or platform due to unplanned shutdown. Besides, solids such as sands, wax, and impurities sometime can cause harm to the pipeline which can increase operating cost by increasing pumping cost due to rough surface of the pipeline. So, there must be some alternative need to be taken before the problem exists or during the operation. Slug catcher usually will be installed upstream of the most of unit operation to stabilize the crude to be processed. However, even lot of action has been considered there is also problem persists which end-up with some operational issues such as pressure loss, off-spec products, etc. Once the problems found during the operation then the pipeline need to be rectified.

Pigging is usually a common used method during construction and operation. During construction the pig launcher play a role such that the pigging process can be used for debris removal (onshore and offshore), gauging, measuring, cleaning, flooding for hydro-test, dewatering and drying, and some other specialized applications. During operation the pig launcher is being used for product’s separation (if batch process is carried out for different products), wax removal, line cleaning, condensate clearance, corrosion inhibition, meter proving, and some other specialized applications. So, this pigging is one of method commonly used to prevent, monitor, and rectify any slugging consequences which can cause to the shutdown of the plant/platform.