METHODOLOGY & PROCEDURES
- The materials required for the project is checked, formulated and identified from the warehouse before being delivered to project site.
- This also follows the foaming machine with air compressor to be used for the project with skilled operators.
At Job Site:
- Occular inspection is necessary with a representative from the client (EEI). By doing this, we can discuss our other concerns like erection of scaffoldings (to be supplied and done by EEI) so that to avoid unnecessary delays in execution of work.
- Joint checking of all materials and accessories from a container van with EEI representative.
EXECUTION: TANK INSULATION and INSTALLATION OF PRE FABRICATED CLADDING (COLD END)
- The aluminum bands, spacer blocks and glue are requested and withdrawn from warehouse.
- Handling – from the container van, the accessories are personally delivered at the working area.
- Measure the tank (ex. T-08) circumference including the thickness of the insulation plus 250mm from overlapping.
- Cut aluminum band.
- Mount spacer blocks with silicon to adhere to the aluminum band. The first block is mounted 150mm from the beginning of the aluminum band, and subsequently the next blocks with a distance of 200mm and so forth.
- The bands with blocks are placed around the tank.
- The first band is placed at the welded joint of the bottom with pop rivets.
- The second band is placed with a distance of 1000mm from the first band and the next bands only with a distance of 900mm.
- The last band is assembled also at the welded joint of tank head regardless of the distance from the last band.
- Bottom and Tank head is also mounted with blocks.
- Double-sided tape is placed first starting from the welded joint and to other side welded joint. Continue until at least two bands are crossing each other in the middle.
- Then place the blocks on tape with a distance of 200mm between each blocks.
- Assembly of aluminum bands from tank head down the bottom in vertical position in five equal distances to support the bands around the tank.
- Withdrawal of supplied bottom-cladding materials from warehouse.
- The bottom is supplied in four pieces according to the size of the tank and is assembled before mounted on the tank.
- After having the bottom assembled, four personnel guided by one skilled cladder carefully mount it. Then, drill hole using electric drill with a size of 1/8” on shell of the bottom and fastened with blind rivets using hand riveter on the first aluminum band at the welded joint.
- Apply oil/wax on the bottom internal.
APPLICATION OF POLYURETHANE FOAM
- Set the machine near the work area.
- Place the transfer pump in their corresponding drums and connect it to the machine.
- Turn on the foam machine and let the chemicals circulate to the machine, by doing these operators can check if the machine is dispensing properly.
- Install the injection gun.
- Before injecting make a sample by injecting a small amount of chemicals in a plastic bag.
- When ready, foam-in-place system is applied directly to the bottom.
- After the execution of polyurethane, it is now ready for mock up. A Quality Control representative from EEI is present for evaluation and approval.
MOUNTING OF SHELL
- Withdraw the required shell jacket materials from warehouse.
- Assemble the shell before mounting.
- The shell jacket is oiled internally.
- Put the shell over the bottom with a distance of approximately 200mm. The bending of shell should be heading in the direction of the bottom.
- Fastened by blind rivets.
- Application of polyurethane foam.
- The next shells to be mounted are assembled, oiled, mounted and foamed in the same manner as described by the first shell with a distance of 100m.
- The last shell can be shortened in accordance with the length of the tank.
MOUNTING OF LEGS
- Assemble, oil and adapt the legs, then mount rivets on the shell.
- Application of polyurethane foam.
INSULATION AND CLADDING FOR PIPING
- Mounting of polyurethane blocks corresponds to the thickness of the insulation.
- Adhere the tape around the pipe until it is fastened. Then place the blocks one at the time (total of 4) using the tape, which is put on top of the blocks.
- Mount the aluminum cover fastened by blind rivets.
- Injection of polyurethane.
- A safety engineer shall be assigned for this particular work and prior to start of work shall prepare a safety standard procedure applicable at the area.
- Mark the working area and install temporary fences to guard it from non involve worker to enter the area.
- All staff and skilled workers shall wear complete protective paraphernalia’s.
- Scaffolding to be used shall be inspected and shall all in good condition prior to loading of manpower to assure the protection of the worker.
SPRAY POLYURETHANE FOAM APPLICATION:
- Check the weather condition. There must have no rain within the past 24 hrs. and none forecast or expected on the day of work.
- Inspect the roof. Make sure that the roof or substrate is free from dirt, oil and other foreign materials.
- Using a Spray machine, apply a thin coat of primer to ensure the adhesion of Polyurethane foam on the roof.
- Using a Spray Foaming machine, we can now spray apply the Polyurethane foam insulation, minimum thickness is 25mm full foam thickness.
PROTECTIVE TOP COATING APPLICATION:
- Protective coating shall not be applied sooner than 2 hours. After Polyurethane Foam has been applied, to allow PUF to cure and minimize off-gassing. Also the protective coating shall be applied the same day as the Polyurethane Foam to prevent Ultraviolet degradation of the PU Foam.
- The completed protective coating shall be inspected. In case of pinholes in the coating, additional layer of coating must be applied.