Mechanical Spiral Wound Pipe Lining (SPL) Technical Services

Mechanical Spiral Wound Pipe Lining (SPL) technology, also known as MSW (Mechanical Spiral Wound). This is a rehabilitation method where profile strips are introduced into the original pipe and spirally wound to form a continuous liner, after which the annular space between the liner and the host pipe is filled.

Through continuous R&D and innovation, Qingyuan Technology has evolved four distinct construction methods: Steel-Plastic Composite Reinforced (MSW-ST), Self-Propelled (MSW-MT), Expansion Method (MSW-EX), and Tight-Fit (MSW-TF/RO). These can be applied to different scenarios based on the specific operating conditions.

Technical Benefits and Features:

1、Large Diameter Compatibility: Suitable for DN200–DN5000 pipes (reinforced concrete, steel, plastic, etc.).

2、 Live-Flow Operation: Suitable for installations with water levels up to 70cm and flow velocities up to 1m/s.

3、Small Footprint: Utilizes existing manholes for access; no large excavation or extensive working pits required.

4、 Operational Flexibility: Construction can be interrupted and resumed at any time. Minimal Traffic Impact: PVC profiles can be cut or reconnected easily, allowing for flexible scheduling and phased construction to minimize social and traffic disruption. (Ideal for emergency repairs, rain, or temporary road reopening)

5、Structural Reinforcement: Forms a "pipe-within-a-pipe" with grouting to reinforce aging infrastructure.

6、 Stable Quality: Prefabricated profiles from the factory combined with onsite mechanical winding ensure consistent quality.

7、Seismic Resistance: The mechanically wound pipe possesses an inherent seismic resilience.

8、Cost-Effective: Superior to open-cut methods, saving on both investment costs and project duration.

Qingyuan Technology has independently developed and implemented the Steel-Plastic Composite Reinforced (Stationary) Mechanical Spiral Wound (MSW) trenchless rehabilitation technology. This method allows for onsite fabrication of liners in various diameters and specifications to rehabilitate target pipes. This technology was developed through in-depth research into material formulation, equipment/mold improvement, and the optimization of PVC profiles and steel strip structures. This process involves using PVC profiles with a double-locking mechanism to wind a new pipe inside the old one in a spiral form. Grout is then injected into the annular space between the host pipe and the liner to form a high-strength composite structure. Application: Suitable for large-diameter pipe rehabilitation. Diameter Range: DN600mm – DN2600mm.

Equipment Components: Stationary mechanical winding machine, hydraulic power unit, U-PVC profile decoiler, profile feeding device, steel strip pressing equipment, grouting equipment, power generators.

The stationary mechanical pipe-fabrication machine is introduced into the roadside manhole through a component-based assembly process. Factory-prefabricated U-PVC profile strips and steel bands are transported to the construction site and fed into the manhole. Driven by a hydraulic power unit, the pipe-fabrication machine operates within the manhole to spirally wind these materials into a brand-new, continuous pipe inside the existing pipeline designated for rehabilitation. Finally, a grouting treatment is performed to fill the annular space between the existing host pipe and the newly formed one, creating a high-strength composite pipe system that achieves the intended objective of structural reinforcement and full rehabilitation.

Within the host pipe designated for rehabilitation, a self-propelled winding machine is constructed and deployed. The PVC profile strips, which are prefabricated at the factory and transported to the construction site, are fed into the working shaft and then conveyed to the machine. Through the operation of this self-propelled unit, the profiles are spirally wound into a brand-new internal pipeline. A specific annular gap is intentionally maintained between the new liner and the host pipe; by injecting grout into this space, a high-strength composite structural system is formed in combination with the original pipeline. The self-propelled machine can be customized to match the shape of the pipe. Application: DN1200–DN5000 for circular, egg-shaped, rectangular, and irregular-shaped pipes.

Within the host pipe to be rehabilitated, a self-propelled machine is erected and deployed. The PVC profile strips are prefabricated at the factory and transported to site, then fed into the manhole. The self-propelled unit winds these profiles into a brand-new pipeline. This specific machine operates in close contact with the inner wall of the host pipe during construction, thereby eliminating the need for subsequent grouting. This method is suitable for circular pipelines with a diameter range of DN1000–DN1800.

Within the host pipe, a stationary winding head is used to wind specialized PVC profile strips into a liner with a diameter that is initially smaller than that of the original pipe. A stainless steel wire is pre-embedded within the locking mechanism (interlock). Once the winding process is complete, the steel wire is pulled from inside the pipe to cut the temporary lock. The resulting inherent spiral expansion stress then forces the pipe to expand until it fits tightly against the inner wall of the host pipe. Suitable for the rehabilitation of circular pipelines with a diameter range of DN300–DN600mm. This rehabilitation method does not require any grouting treatment.