YDC Types Stressing Hydraulic Hollow Core Jack Multi Strand Post Tensioning Jack

Features of Hydraulic Core Hollow Jack​

1. YDC Types Stressing jack is a general-purpose prestressed through-heart jack, which is used for tensioning operations of various steel strand anchorages. Widely used in post-tensioning large buildings, structures, prestressed concrete bridges, rock anchoring, hydraulic structures, foundation anchoring, and other major projects.
2. The main parts of the jack are made of high-strength steel, which has the characteristics of compact structure, lightweight, small volume, short axial length, and short reserved tension length of steel strand, which can save steel strand material. And the hoisting is flexible, durable, easy to operate, and easy to maintain.
3. YDC type jack is a kind of feed-through jack, which is a multi-purpose prestressed tensioning equipment. It is easy to operate, mainly used for single-hole tensioning, and can also be used for long and short preloading. Tensioning and troubleshooting, and suitable for high-strength steel wire bundles and strands of various specifications.

Diagram of Hydraulic Core Hollow Jack

1, positioning nut 2, plug 3, ring 4, cylinder 5, piston 6, heart sleeve 7, ring 8, oil nozzle 9, sealing plate 10, compression ring

Installation of Post-Tension Jack and Anchorage

1. The steel strand shall be threaded into the reserved gallery of the structure, and the exposed length of the steel strand at the tensioning end is required to be 200-250mm longer than the working length of the jack. The steel strand must be cut with a thin disc grinder without loose ends or "rough ends" to avoid difficult perforation.

2. Cover the end of the steel wire bundle of the working anchor plate, push it to the anchor base plate, and align it with the spigot.

3. Installation of working anchor clips: before installing clips, use steel rings to clamp each pair of clips together, then push them into the taper hole of the anchor plate along the steel strand, and then push them until they do not move.

4. Installation of limit plate: the limit plate is designed according to the working anchor plate and matched with the hole of the anchor plate.

5. Installation of jack: first bind the end of the steel strand bundle with a wire pin, then lift the jack and put it on the steel strand, and put the support opening of the front cover of the jack on the outside of the limit plate. At this time, the jack can be coaxially aligned.

6. Install the tool anchor on the support lip at the end of the piston.

The jack is used in combination with the supporting oil pump. The tensioning oil circuit of the oil pump is connected to the jack tensioning cavity nozzle, and the calibrated pressure gauge is also connected to the oil circuit. The return oil circuit of the oil pump is connected to the return oil nozzle of the dry catty top, and the safety valve of the oil circuit is adjusted to 10MPa to ensure safety.