1. Calculate the theoretical elongation value of the steel strand: the tension is conducted by the method of controlling the stress and elongation with double control and upper arch degree check, and the actual elongation value should be within + / - 6% of the error of the theoretical elongation value.
2. Check and verify the tensioning jack and oil pressure gauge before construction. When the jack is used more than 6 months or 200 times, or abnormal phenomena occur during operation, it should be checked again after maintenance.
3. Check the anchor plate and channel. The channel should be free of moisture and debris.
4. Installation of anchor and jack: install anchor, clamp, limit plate, jack, tool anchor and adjust the position of jack, so that the tension action line of jack coincides with the axis of prestressed steel strand.
5. Set up the tension platform and protective plate. To make the iron frame, place the iron frame close to both ends of the beam before tensioning. The jack and chain are suspended on the iron frame, and the protective plate is installed at 1.5-2.0m away from the jack. The material is steel formwork, the width and height are more than 2 meters, to prevent the anchor clamp from popping and hurting people.