Cathodic protection strip zinc alloy sacrificial anode

Strip zinc alloy sacrificial anodes are primarily used in high-resistivity environments, such as the protection of pipelines within casings, temporary cathodic protection of pipelines, protection of storage tanks and pipe networks, and grounding grids for strong electrical interference protection. Their installation method is relatively simple, and compared to impressed current cathodic protection, the installation of sacrificial anodes is more convenient.

The usage method of strip zinc alloy sacrificial anodes mainly includes the following steps:

1. Preparation:

   • First, uncoil the zinc anode strip and avoid sudden bending in low-temperature environments to prevent breakage. Cut it to the specified length according to design requirements.
   • Check the surface of the zinc anode strip for oil stains and remove any debris with a cloth or sandpaper.
   • Use tools such as a hacksaw and pliers to expose 20 mm of the iron core at both ends of the zinc strip, polish it with sandpaper, and then cover it with a heat-shrink tube.
   • Strip 20 mm of the copper core of the cable, sleeve the iron core and the copper core of the cable with a copper tube, and compact it with a hydraulic lead press.
   • Check the conductivity at the connection point to ensure the contact resistance is no greater than 0.01Ω.
   • Seal the joint and tighten it with a heat-shrink sleeve.

2. Installation Steps:

   • According to design requirements, lay the zinc strip anode alongside the pipeline or wrap it around the pipeline, and connect the cable as required.
   • If space permits, the minimum distance between the zinc anode and the pipeline should ideally be within 3 meters to meet the spacing requirements.
   • When using a magnesium strip to protect the tank bottom plate, a galvanized flat iron can extend from the center of the storage tank to the outer side of the tank bottom plate, and the iron core of each loop of the magnesium strip can be welded to the flat iron.

3. Maintenance and Inspection:

   • Regularly check the output current of the anode and replace it promptly after the anode is depleted.
   • Check whether the goods qualification certificate and packing list are complete, and whether the anode lead wire is intact and undamaged.
   • Check whether the anode is centered in the filler bag, excavate the anode pit at the designated location according to design requirements, and place the anode in the pit.
   • Open, clean, weld the lead wire, and seal the pipeline coating; guide the cable to the test station; soak the anode with clean water, and then backfill.