A record is prepared to document the results of the bonder qualification. After examination of the completed joints, the final step in ensuring the joints have been properly made is the performance of a hydrotest.
ASME B This is usually accomplished with a hydrotest at a pressure of 1. The pressure is held for a minimum of 10 minutes after which the joints must be examined for leaks.
Bonding operations for FRP piping are not difficult to do well. This is the last article in the series. If you have any questions, or if your team would like to arrange a Lunch and Learn with our Engineers, please contact us. Previous article in the series: Properly Functioning Support System. Those are the minimum values.
Upon satisfactory completion of inspection and testing on pipes, fittings and spools, the organizations responsible for design, construction and inspection shall furnish copies of the certificate to the Purchaser, stating the design, construction and testing complies with this specification and selected code. Detailed design drawings shall be prepared by the Vendor and submitted for Purchaser approval prior to start of manufacturing.
All important construction details must be shown in details-drawings. The Manufacturer shall provide quality control test reports. Manufacture shall submit a certified record of inspection and testing together with a statement of compliance with the requirements.
These shall also include the relevant certificates for metallic parts, if any. Additionally, requirements of Owner in regards certification stipulated in his specification shall be met. The installed pipe lines shall be hydro-tested. The entry attendant remains outside the space to constantly monitor by visual or auditory communication authorized entrants working inside the space. Grind the above area to remove the topcoat and surface layer of the pipes until the pipes glass fiber are exposed.
Mix the resin and hardener as per the quantities specified in the recipe to maintain the right ration. Wait till the lamination is cured under ambient temperature. The curing time of the fit layer ranges between 1 to 2 hours depending on the sunlight. Grind the above area to remove the topcoat and surface of the pipe until the pipe glass fiber are exposed.
Depending on the pipe diameter and pressure class, the type of glass and the number of layers are specified in the lamination recipe. If only glass should be used, skip all the below steps except the last one to end up the lamination with two layers of top tape. Otherwise move the next step. Repeat the above two steps till the required number of layers is applied. If more should be applied, move to the following steps. Otherwise skip all the below steps except the last one to end up the lamination with two layers of Top Tape.
Apply the specified number of layers of woven roving and alternatively. Each type of glass should be applied in four consecutive layers before changing to the other type. Every two layers should be impregnated before applying the second two layers of the same type. Wind two layers of top tape glass around the laminate to extract the excess quantity of resin and to provide smooth surface.
The lamination is cured under ambient temperature. Make sure that the joint is undistributed until it cures. The curing time varies between 4 to 8 hours depending on the sunlight exposure and temperature. Cover the above laminate with two layers of C glass surface veil material surface mat to provide a smooth resin-rich laminate surface.
For internal lamination, the plies edges shall be penetrated into the previously made grooves at both side of the lamination width to maintain smooth flow of the product during operation. The prepared bond surface area should be free from grease, oil, dust, moisture, water, etc. Clean the surface using a clean and dry cloth or a dust brush. Lamination should be stopped in case resin starts gelling. To continue the laminate, surface should be abraded.
Internal lamination shall be done immediately after completing the external lamination to limit the entry distance to a standard grp pipe length. There should not be any dirt, dust, or moisture on the overlap area.
Line up the insulation properly over the pipe and close it. Make sure the adhesive on the jacket does not contact anything while sealing the insulation.
Now the next step is to pull the release strip from the jacket lap carefully. We recommend starting it by removing the lap down the middle till the adhesive starts touching the adhesive strip on the jacket. Press together and firmly rub while squeezing from the center toward the end.
Check if the lap securely adheres to the jacket. Complete the procedure by applying the matching butt strip. Rub firmly for the positive closure.
Keep enough tape to make sure the piping system is completely sealed. Use sharp knives for easy cutting. The clear spacing between adjacent pipes must be at least 0. When an unstable soil condition is encountered that is caused by a water table, the bottom of the trench must be drained before laying the pipes. This can usually be accomplished by lowering the water table to approx. To minimize the soil dewatering, only a length of trench to place one or two sections of pipe should be opened and then be backfilled.
The foundation shown in the above figures is required when the trench bottom is unstable, i. According to the different conditions of instability for the trench bottom, the installation contractor may require different types of foundations such as:. The above indications must be more closely followed as the diameter of the pipe to install is larger.
Please take note that by increasing the fines content of the material, the energy required for the tamping of the material itself will increase. To install the pipes, the following procedure can be used, as a function of the type of joint and of the pipe diameter:.
Compaction can be made by using a pulse compactor or other suitable systems. In case the backfill is composed of sand, the compaction can be obtained by saturation.
If this method is used, it is necessary to verify the draining capacities of both the bed of the trench and of the native soil; if necessary provide suitable drainage systems and use an adequate quantity of water, in order to prevent the pipe from floating.
The laying trench should be filled up as soon as possible, as far as ground level or for a height of 1. If the installer is given the possibility to change one of the above parameters, in the following table is shown the Modulus of Soil Reaction that can be achieved with different materials and soil densities.
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