Post-tensioning is a method of reinforcing (strengthening) concrete or other materials with high-strength steel strands or bars, typically referred to as tendons. Post-tensioning applications include office and apartment buildings, parking structures, slabs-on-ground, bridges, sports stadiums, rock and soil anchors, and water-tanks. In many cases, posttensioning allows construction that would otherwise be impossible due to either site constraints or architectural requirements.
Although post-tensioning systems require specialized knowledge and expertise to fabricate, assemble and install, the concept is easy to explain. Imagine a series of wooden blocks with holes drilled through them, into which a rubber band is threaded. If one holds the ends of the rubber band, the blocks will sag. Post-tensioning can be demonstrated by placing wing nuts on either end of the rubber band and winding the rubber band so that the blocks are pushed tightly together. If one holds the wing nuts after winding, the blocks will remain straight. The tightened rubber band is comparable to a post-tensioning tendon that has been stretched by hydraulic jacks and is held in place by wedge-type anchoring devices.
Products of Iron castings for Post Tension System
CFS specialises in the design and supply of iron castings for the application of post tension system. Our iron castings can meet or exceed the requirements of the Post Tension Institute and International Building Code. Below are the main iron castings we can supply:
Monostrand Anchor Castings for Unbonded Post Tensioning Application
Flat Slad Anchor Castings & Wedge Blocks for Bonded Posting Tensioning Application
Materials of Iron Castings Used for Post Tension System
Ductile iron: Also known as ductile cast iron, nodular cast iron, spheroidal graphite iron, spheroidal graphite cast iron and SG iron, is a type of graphite-rich cast iron .While most varieties of cast iron are brittle, ductile iron has much more impact and fatigue resistance, due to its nodular graphite inclusions.
Grey iron: Or gray cast iron, is a type of cast iron that has a graphitic microstructure. It is named after the gray color of the fracture it forms, which is due to the presence of graphite. It is the most common cast iron and the most widely used cast material based on weight. Gray iron is a common engineering alloy because of its relatively low cost and good machinability, which results from the graphite lubricating the cut and breaking up the chips. It also has good galling and wear resistance because the graphite flakes self lubricate. The graphite also gives gray iron an excellent damping capacity because it absorbs the energy and converts it into heat.
Why Casting?
- Casting is a process that molten metal flows into small ant section in the molten cavity. Hence any complex shape metal parts can be easily produced for post tension system.
- Due to the special features of iron material, any cast iron alloys can be casted.
- Casting is an ideal method is by producing both small and large quantities.
- Due to small cooling rate from all directions, the properties of casting are same in all directions.
- Any size of anchors or wedge blocks can be casted in iron for post tension system.
- Casting is the often cheapest and most direct solution of producing components for bonded or unbonded post tension system with desired mechanical properties.
Why CFS for Post Tension Castings?
- CFS can offer great quality assurance for your iron castings used in post tensioning. We have a district quality control system to inspect both material, dimensional tolerances and mechanical properties. NDT will be operated to protect castings from damage.
- Our precoated sand casting process is the most precision casting method for producing such iron castings. This will greatly reduce machining operations and save cost.
- With value added machining service, we can supply machining as well after casting. So our customers can enjoy price advantage and short lead time.
Contact us now if you are sourcing a reliable supplier for such products.
