Technical Instructions
UPVC
UPVC pipes production range:
Pipes Storage, handling, and transporting.
Recommendation during installation
Trench width and depth
Site Pipeline Pressure and Leakage Test
UPVC pipes production range:
- UPVC pipes are manufactured according to German, American, British, and Egyptian Standards for potable water, waste water, irrigation, and industrial uses in addition to perforated and well pipes.
- UPVC pipes are produced six meter long including socket and spigot and in some cases according to customer request pipes can be produced in six meter length excluding insertion length.
- UPVC pressure pipes are produced in white color for American Standards ASTM and in Grey color for German and British Standards.
- UPVC pipes are joined by solvent cement for sizes from 32 up to 75 MM and the higher sizes by rubber rings.
Pipes Storage, handling, and transporting.
Storage
- Pipes can be stored in bundles or loose pipes in any cases it should be stored on flat surface free of any sharp objects.
- Pipes should be given adequate support at all times, Side supports should be provided at intervals of not more than 1.5 m should preferably be batten of wood 7.5 cm
- Pipes should be uniformly supported throughout their entire length. If this is not possible, timber battens at least 75 mm wide timber supports should be placed beneath the pipes with spacing not greater than 1 meter.
- Pipes stack should not exceed 6 layers, with a maximum height of 2 meter height.
- Pipes packed in bundles can be stored up to 3 bundles.
- Pipes should not be stored for extended periods under direct sunlight to avoid ultraviolet degradation. Even if the pipes are stored under cover the storage temperature should be maintained at 20 –25 o C.
Handling
- Plastic pipes are flexible light weight; in spite of its toughness care should be taken when unloading the pipes not to drag the pipes on the ground to avoid scratching the outer surface. Loading or unloading is carried out; it is recommended to use cotton or nylon (synthetic) belts to avoid damage to the pipes. If metal slings are used, the pipe should be protected against scratches.
Transportation
- Vehicles with a flat bed should be used for transport of pipes. The bed should be free from nails and other projections. Each pipe should be supported uniformly along its length.
Recommendation during installation
- Please follow the instruction in the Egyptian Code of installation for pipelines and water network before installation.
- Review the soil type from the consultant report before proceeding with pipe installation to decide the amount of sand required as bedding beneath the pipes, on both pipe sides, and above the pipes.
- Check the rubber rings carefully and clean them before installation. Be sure of the alignment of pipes during joining and use the proper joining lubricant.
Trench width and depth
- Trench width: It is important to take precautions against trench collapse. Do not open trenches too far in advance of pipe laying. Support the sides of trenches that are deeper than 1.2
- meters. Keep trench width as narrow as practicable but not
less than 300mm wider than the pipe diameter, i.e. 150mm clear each side of the pipe to allow proper compaction of the side fill.
Laying of pipes
- General: all pipes, fittings, and valves shall be carefully lowered into the trench using suitable equipment in such manner as to prevent damage to pipe and fittings. Under no circumstances shall the pipes be dropped or dumped into the trench.
- Pipe and fittings should be visually inspected for defects prior to lowering into the trench.
- Any defected or damaged part must be replaced before lowering the pipeline into the trench. The open ends of the installed pipes should be closed to prevent entrance of foreign materials in the pipeline.
Bedding and back filling
- General: The flexibility of plastic pipes and joints help them to withstand damage resulting from ground movement or from other differential settlement. They derive an important part of their strength from the support of bedding and sides fill. The horizontal resistances of the side fill limits any horizontal deflection of the pipe caused by the vertical load. A state of equilibrium is reached when the horizontal reaction corresponds to the transmitted vertical load.
Site Pipeline Pressure and Leakage Test
The purpose of the site pressure is to ensure that the installed section of line under test and all joints and fittings included in the section will withstand the design working pressure plus a safety margin without leakage.
A. Before pressure testing the following guidelines should be observed:
- End caps are mounted on all ends of the pipeline.
- Insert air bleed valves at all the highest points along the pipeline.
- A- piped water supply and sanitation with the pressure.
- Allow 24 hours after welding before test.
- The line should be filled with water 24 hours prior to the start of the test.
- Ensure that the system is entirely ventilated.
- Backfill the pipeline before test
- Leave joints exposed
- Test with all valves fully open
B. During pressure testing the following should be observed:
- Ensure that all air bleed valves are open and working.
- Slowly fill the pipeline with water avoid damage due to pressure surge
- Gradually raise the pressure to a pressure corresponding to 1.5 times the nominal pressure class the pressure is maintained for 2 hours.
- Supplementary filling of water allowed. During the following 60 minutes water should not be added. After 60 minutes the pressure is measured and the water is added until the pressure is again 1.5 times the nominal pressure class.
- The fall in pressure and the amount of water added should not exceed the following limits:
- Pressure drop in percentage of the initial pressure = 2%
- Water quantity in liters/ meter = 0.2 Di – 0.001 + DV
- Where DV = 0.05 x d2
- Di is the inside diameter
