Products · Wedges
Anchor wedges and master wedges.
Wedges are what actually hold the strand. A set of three case-hardened segments seats in each hole of the anchor head and bites the strand as the jack releases it.
How a wedge locks the strand
Each strand passes through a tapered hole in the anchor head. A three-piece wedge, held together by a circlip, sits around the strand in that hole. When the jack lets go, the strand pulls back a few millimetres, the wedge is drawn into the taper and its serrated bore grips the strand. That small movement is the wedge draw-in recorded on the stressing record.
Anchor wedges are sized to the strand they grip: 12.9 mm wedges for 12.7 mm strand on AT 13 heads, and 15.2 mm wedges for 15.2 mm strand on AT 15 heads. They are used once and stay in the structure.
Master wedges are a different part
Master wedges sit in the gripper of the multi-strand jack, not in the structure. They are larger and longer, through-hardened, and built to survive hundreds of stressing cycles before the teeth wear and they are replaced.
Need it installed and stressed as well? TYROS crews do that too: post-tensioning stressing services.
TYROS wedge families
| Wedge | For | Segments | Material | Hardness |
|---|---|---|---|---|
| 12.9 mm anchor wedge | 12.7 mm strand (AT 13 heads) | 3-piece | Case-hardened alloy steel (20MnCr5 / 20CrMnTi) | Surface 58–62 HRC, tough core |
| 15.2 mm anchor wedge | 15.2 mm strand (AT 15 heads) | 3-piece | Case-hardened alloy steel (20MnCr5 / 20CrMnTi) | Surface 58–62 HRC, tough core |
| Master wedge | 12.9 mm and 15.2 mm | 3-piece | Through-hardened EN36 / 20MnCr5 nickel-chrome steel | 58–60 HRC through, longer body |
Wedges questions.
Asked by designers and contractors before ordering.
What is the difference between 12.9 mm and 15.2 mm wedges?
The size is the strand they grip. 12.9 mm wedges are for 12.7 mm strand (AT 13 heads); 15.2 mm wedges are for 15.2 mm strand (AT 15 heads).
Can anchor wedges be reused?
No. Anchor wedges are one-time use and stay in the anchor head. Master wedges in the jack are the reusable ones.
How many wedges does one anchorage need?
One three-piece set per strand: 12 sets for a 12 AT 15 anchorage, 19 sets for 19 AT 13.
The rest of the AT anchorage
- Anchor cone for post-tensioning
- Anchor head for post-tensioning
- Spiral reinforcement for post-tensioning
- HDPE sheathing duct for post-tensioning
See all five models together on the AT anchorage system page.
Send us the tendon schedule. We'll send back the anchorage.
Anchorage specifications, anti-burst reinforcement details and the stressing methodology — for every contractor, on every job.
Need the tendons stressed too? See our post-tensioning stressing services.