Question: For the installation of tee joints for directly buried insulated pipes, should one choose pre-made tee joints with good insulation properties, or should holes be drilled in the insulated pipe and welding be carried out on site?
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Question: 1. For the construction of tee joints for directly buried insulated pipes, should one choose pre-made tee joints with good insulation properties, or drill holes and weld on the insulated pipe on site? 2. For the construction of bends in directly-buried insulated pipes, should prefabricated bends with good insulation be used, or should bends be fabricated on-site and then insulated at both the bends and the welds? 3. Are there any atlases that can solve similar problems mentioned above? Which one? 4. How wide of insulation needs to be removed from the weld area to create a suitable welding surface? Which specification or atlas specifies it? 5. Recently, while reviewing a settlement document, I found that only the pressed elbows were specified, but no insulation for those pressed elbows was included. This gives rise to the aforementioned issues. I hope the expert will kindly share his insights!
Different industries may have different construction methods*
05R410 Hot water pipe direct burial installation
1. The decision is based on the actual conditions on site; for example, if the cost of purchasing a finished elbow is much higher than that of an elbow with a drilled hole, then an elbow with a drilled hole is chosen. 2. Same as 1, for ease of construction. 3. The catalog doesn’t require the use of finished products or on-site prefabrication, right? 4. If the insulation material is flammable, the insulation must be removed from the entire welded area. But generally, whether flammable or not, it is removed; your question may relate to the issue of re-insulation during settlement or the reuse of materials. 5. The volume of work for insulation is calculated based on length, so no insulation is provided for pressed elbows.
The stress at the tee joint is relatively high; therefore, the wall thickness of the tee should be increased or reinforcement ribs should be added. For spot welding, stress can be tolerated for smaller pipe diameters; for larger diameters, it’s not possible