Metal bellows are metal pipes and connecting pipes made of galvanized or non-galvanized low-carbon steel strips with spiral folded joints.
Used for drilling holes in post-tensioned prestressed concrete structures or components.
Metal pipes can be selected as seamless pipes or corrugated pipes according to the designed strength. The purpose of pre-embedded metal in the post-tensioning method is to leave space for placing steel tendons.
The use of bellows can reduce channel friction and reduce losses.
ID | 50 | 60 | 65 | 75 | 90 | 100 | 105 | 115 | 125 | 130 |
---|---|---|---|---|---|---|---|---|---|---|
OD | 55 | 65 | 70 | 80 | 95 | 105 | 110 | 120 | 130 | 135 |
Deviation tolerance | ±0.50 | |||||||||
Thickness of standard steel strip | >0.3 | |||||||||
Thickness of reinforced steel strip | >0.32 | >0.4 | >0.6 |
Note:
Short Axis | Length | 24 | 24 | 24 | 24 | 24 | 24 | 24 | 24 |
---|---|---|---|---|---|---|---|---|---|
Deviation tolerance | +3/0 | +3/0 | |||||||
Long Axis | Length | 55 | 65 | 75 | 95 | 55 | 65 | 75 | 95 |
Deviation tolerance | ±1/0 | ±2/0 | |||||||
Thickness of steel strip | 0.3 |
Type | Min center distances(mm) | support distances up to(m) | Type | Min center distances(mm) | support distances up to(m) |
---|---|---|---|---|---|
T13-04 | 90 | 1 | T15-04 | 108 | 1 |
T13-07 | 108 | 1 | T15-07 | 117 | 1 |
T13-12 | 117 | 1 | T15-12 | 162 | 1 |
T13-15 | 162 | 1 | T15-15 | 180 | 1 |
T13-19 | 162 | 1 | T15-19 | 180 | 1 |
T13-22 | 180 | 1 | T15-22 | 189 | 1 |
T13-25 | 189 | 1 | T15-25 | 207 | 1 |
T13-27 | 189 | 1 | T15-27 | 207 | 1 |
T13-31 | 189 | 1 | T15-31 | 207 | 1 |
Min support distance conform to the standard of public construcation commission.
Corrgated plastic duct ase usually used at the project of un-bonded bridge or outer post-tensioning design.
The beneficial parts for plastic duct than steel duct are the lower production cost, stronger durability, and last for environment consideration.
the less consume for steel material, the better for our earth.
ID | OD | Thickness |
---|---|---|
50 | 56 | 3 |
55 | 61 | 3 |
60 | 66 | 3 |
65 | 71 | 3 |
70 | 76 | 3 |
75 | 81 | 3 |
80 | 86 | 3 |
85 | 91 | 3 |
90 | 96 | 3 |
95 | 101 | 3 |
100 | 106 | 3 |
105 | 111 | 3 |
110 | 116 | 3 |
115 | 121 | 3 |
120 | 126 | 3 |
125 | 131 | 3 |
130 | 136 | 3 |
ID | OD | Thickness |
---|---|---|
41 | 45 | 2 |
46 | 42 | 2 |
55 | 61 | 2 |
60 | 33 | 2 |
72 | 78 | 2 |
90 | 96 | 2 |