PC Wire & PC Strand Installation Instruction
No.1 Storage
Prestressed Concrete Steel Wire & Strand should be stored in dry warhouse. Please put them on the sleeper if stored in the open air of working filed and cover the awning cloth or rain-proof shed, and forbid the Wire & Strand touched the wet ground directly. Make the storage time as short as possible, and anti-rust packing should be used if in the special environment. The free rust on the surface of the product will not make any bad influence in the actual using,but it will affect the mechanic function of the product if the rust change into some holes which could be see by eyes.
No.2 Hoisting
The prestressed concrete steel wire and strand should be hoisted orderly and make
some room between two parts. Parallel hoisting the unbonded prestressed stand
adopting three button holes of coir rope, and forbid hoisting it directly by the steel cable. Pls use forklift or the appropriative lifing crane for lifting the steel wire or strand rolls to prevent the product unreel once the steel strip are broken off .
No.3 Use
1. Any way of heating to make the prestessed steel deformed is forbidden in using to avoid the mechanical function of the prestressed steel wire or strand are reduced.
2. Forbid to weld in use, because the tensilestrength of the welding spot is much
lower than that of the prestressed steels, and the spot is easy to break off when the steel
is stretched.
3. Cutting the presstressed steel products should use the toothless saw(grinding wheel saw). Electric cutting can injurethe surface of steel easily, and make part of the terminal
hot at the same time, which will reduce the function.
4. When the prestressed steel wire adopts the circulating reinforcement, its bending radius is not less than 3 times the diameter of the steel wire.
5 The strand in rolls and without wheel packing should be unreeled from the inner tapping line in the vertical condition.The
strand unreeled shaped as spring and unbend directly. The unreeled direction: the spire
direction of the unreeled spring should be conformity with the lay direction of the strand,
otherwise the unreeled strand will twisted or the strand twisted together.
6. The twist direction of strand is left commonly. It should be noted in the contract if
used in right twist direction, otherwise it will make a bad influence in the cooperation
with the anchorage.
7. The quality of the prestressed steel wire upset head is not directly related to the quality of the steel wire itself. The excessively high strength will not be good for the quality of the upset head. Therefore, when you use the upset head to anchorage, pls state it in the order.
No.4. Inspection and Acceptance
1. Prestressed steel's inspection and acceptance should be made according to the national standard. The inspection equipment should be national legal instruments and conform to the regulation of the inspection standard.
2. If quality problems occur during acceptance inspection, please pay attention to whether the following items meet the requirements.
(1)Whether to use the updated international standard and test ways to inspect and accept.
(2)Whether the tonnage of the testing machine is proper or not, or the measurement equipment is accurate , or steel fracture is cutting by the grinding wheel saw or not,
or use the nominal area to calculate the strength or not.
(3)Whether the bending tester's bending bayonet conform to the national standard and
regulations; Whether the surface of bayonet meets the standard in terms of smoothness, clearance height and bending Angle.
(4) The elongation of the pc wire & strand shall be measured by a sharp, standard engraved distance tool and shall not damage the surface of the pc wire & strand.
(5) Whether the pc wire or strand itself has serious rust or artificial surface damage caused by storage
No.5 Unreeling
Before used, prestressed steel must be unreeled by the unreeling machine.
