How to Connect Water Pipes in Prefabricated Houses

Connecting water pipes in prefabricated houses requires standardized installation methods based on the type and scenario, which can be divided into three categories: prefabricated modules in prefabricated buildings, traditional prefabricated houses, and general installation principles. The key operating points are as follows:

I. Connection of Thin-Walled Stainless Steel Water Pipes in Prefabricated Modules of Prefabricated Buildings

1. Connection Technology and Materials
   Adopt crimping or ring-pressing solder-free connection technology, using specialized electric tools to ensure proper crimping. The jaw size must precisely match the pipe diameter (e.g., a pressure of 20-25 MPa for a DN15 pipe diameter). The pipe material should be 304 or 316L thin-walled stainless steel pipes conforming to the GB/T 19228.2-2011 standard, with a wall thickness of 0.6-2.0 mm.
2. Laying and Fixing
   The pipes are fixed using pre-embedded metal or composite supports and hangers. For horizontal pipes, the fixing intervals should not exceed 1.5 meters for DN15-DN25 and 2.0 meters for DN32-DN50. For vertical pipes, at least one fixed support should be installed on each floor, and rubber or plastic liners should be added between the pipes and supports to prevent corrosion.
3. Penetration and Sealing
   When penetrating wall panels or floor slabs, pre-embed waterproof sleeves that are 1-2 sizes larger than the outer diameter of the pipes, and seal the gaps with fireproof mud or flexible sealant. When penetrating fire compartments, install fire collars at both ends of the sleeves.

II. Water Pipe Connection in Traditional Prefabricated Houses (e.g., Embedded in Buildings)

1. Construction Stage and Materials
   The embedded pipes should be installed before concrete pouring and fixed within the formwork or steel reinforcement structure. Common pipe materials include PVC pipes, SC pipes (welded steel pipes), and JDG pipes (tight-fitting steel pipes). For bathroom drainage pipes, it is recommended to use finished waterproof sleeves.
2. Connection Specifications
   SC and JDG pipes must not be butt-welded. Instead, use specialized grounding clamps to connect BVR-4MM² yellow-green bicolored wires, and wrap the pipe head locknuts tightly with tape.
3. Position and Spacing
   The outer diameter of pipes embedded in floor slabs should not exceed one-third of the slab thickness, with a distance of ≥15 mm from the surface and a parallel spacing of ≥25 mm between wire pipes. For pipes embedded in shear walls, reserve positions for boxes and enclosures and protect them with seals. When penetrating walls/floor slabs, pre-embed steel sleeves that are 2-3 sizes larger than the actual pipes. For the exterior walls of basements, weld a 5-8 mm steel plate water stop ring.

III. General Installation Principles

1. Installation Sequence
   Follow the principle of "from underground to above ground, from large pipes to small pipes, and from main pipes to branch pipes." Before installation, verify the positions and dimensions of reserved holes and mark the pipe coordinates and elevations.
2. Discharge Pipes and Riser Pipes
   The buried depth of discharge pipes should meet design requirements, and they should be connected flush with the top of outdoor pipes, with a water flow turning angle of ≥90 degrees (unrestricted when the drop difference is >0.3 meters). Riser pipes should be installed along wall corners, with reserved holes when penetrating floor slabs. The distance between the outer side of the socket and the finish should be 20-50 mm, and inspection ports should be installed every 10 meters.

By following standardized operations, the water pipe system can be ensured to be safe, sealed, and durable, meeting the functional requirements of different scenarios.