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THE MOST RELIABLE METHOD FOR
ISOLATING YOUR PIPELINE SYSTEM
FOR REPAIR OR MAINTENANCE
Installation Steps
- Pipe is ultrasonically tested.
- Pipe reinforcing rings are positioned on the pipe, straddling the area to be plugged, and welded in place (Fig.1).
- The pipe holding section is placed in position on the pipe, and secured by welding (fig.2) on any pipe axis.
- Pipe notching equipment is positioned on the pipe holding assembly. Notching can be safely accomplished because axial loads on pipe are transferred through the pipe holding assembly.
- Assembly of the PLIDCO® Shear+Plug is completed by positioning the blind plate housing on the pipe holding section (Fig. 3). Nuts on the through-bolts are securely tightened and the complete assembly is pressure tested.
- The hydraulic cylinder is actuated, thrusting the shear blade through the pipe and pushing the coupon into the coupon receptacle housing, allowing retrieval of the entire coupon (Fig.4).
- The blind plate is indexed. Thrust bolts on the downstream side are tightened, which push the blind plate against the housing wall forming a metal-to-metal seal. The test valve is opened to release downstream pressure and make sure the plug-off is complete.
- While scheduled work is in progress, the coupon receptacle housing is removed - permitting retrieval of the coupon. The first completion cap is welded to the pipe holding assembly. Then the Shear + Plug is reassembled, with the first completion cap in position between the coupon receptacle housing and the pipe holding section.
- Upon completion of the scheduled work, the pipeline is put back on stream. Thrust bolts are loosened; the blind plate is retracted into its receptacle housing.
- After the blind plate is retracted, the retraction cock valve is closed. The Shear + Plug is then disassembled and the second completion cap is welded to the pipe holding assembly (Fig. 5). The pipe holding section remains on the pipe.
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Figure 1
Figure 2
Figure 3
Figure 4
Figure 5
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