How to achieve integrated molding of pipeline parts through metal 3D printing?

一, The technical principle is to build things digitally from powder to pipeline.
To make a solid object in three dimensions, metal 3D printing uses high-energy beams (laser or electron beam) to melt metal powder and stack it on top of each other. For example, the main steps in the Selective Laser Melting (SLM) process are
3D modelling and cutting: Import the CAD model of the pipeline pieces into the slicing software. Then, create layer thickness data that ranges from 0.02 to 0.1 mm and plan the path for the laser scan.
Powder coating and laser melting: The powder coating machine evenly spreads metal powder over the workbench while being protected by inert gas. The high-energy laser beam then selectively melts the powder along the path to create a single-layer cross-section.
Layer by layer stacking and design for support: The workbench goes down in layers, repeating the process of laying down powder and melting it. Adding soluble support structures creates the suspended pieces, which eventually leads to the creation of entire pipeline components.
This technique can handle materials like stainless steel, titanium alloys, nickel-based alloys, and others, and it can satisfy the needs of diverse working circumstances for corrosion resistance, high temperature resistance, and strength. For instance, Cangzhou Longtaidi Pipeline Technology Co., Ltd. uses 3D printing welding technology to melt 3mm thick nickel-based alloy on the inside of carbon steel pipes. This makes bimetallic composite pipes that can handle high pressure and corrosion, which are used in oil and gas extraction.
二, Main benefit: Getting over the four main problems with conventional handicraft
1. Geometric degrees of freedom: exact building of complicated shapes
Tool availability and mould design limit traditional methods, which makes it hard to make complicated pipelines with sharp curves at different angles, spatial spirals, and cross-sections that aren't straight. Also, metal 3D printing can do:
Designing conformal flow channels: For instance, a company in Nanjing printed parts for chemical reactors that had spiral cooling channels built in. These channels improved heat transmission by 40% and kept the temperature from changing by more than ± 2 °C.
Put together: In the past, you had to solder together different pieces of a pipeline system. Now, you can print the whole thing. A maker of medical equipment has combined 12 separate parts into one using 3D printing of microfluidic chips. This has cut down on leaks by 90% and cut the time it takes to put things together from 8 hours to 1 hour.
Lightweight structure: A lattice structure made with topology optimisation, which makes it lighter without losing strength. The aerospace titanium alloy pipeline has a hollow interlayer that was made with 3D printing. This makes it 35% lighter than standard forgings.
2. Production efficiency: the time it takes to switch from weeks to days quickly
The traditional way to make pipelines involves five steps: "design mould development casting/forging machining assembly." This procedure can take up to four to six weeks. And metal 3D printing speeds up the delivery process a lot by using a three-step closed loop of "digital model printing post-processing":
Fast iteration: A certain maker of car parts used 3D printing to make exhaust manifolds and finished five rounds of design optimisation in three days. This cut exhaust back pressure by 18% and boosted power by 8%.
Small batch economy: If you require less than 500 customised pipelines a year, 3D printing costs 40% less per piece than traditional methods, and you don't have to pay for moulds.
Production on demand: Through 3D printing, a nuclear power plant makes emergency cooling pipes on-site. This process takes only 72 hours from design to installation, which is 90% faster than the usual procurement period.
3. Material use rate: from "reducing material waste" to "near nett forming"
The use rate of typical machining materials is usually less than 45%, while "additive" manufacturing is how 3D printing is done:
Correct powder control: The inaccuracy in the thickness of the powder layer can be less than 0.05 mm with SLM technology, and the material use rate can be over 85%. Compared to typical forging methods, the stainless steel pipes made by a certain company use 62% less raw materials.
Using gradient material: By using numerous nozzles to print together, you can change the qualities of the material on the same part. A specific aviation engine's combustion chamber is made of a nickel-based alloy and ceramic composite construction. This makes it 200 °C more resistant to high temperatures.
Re establishing barekamp: Unmelt-bound powder can be Town donations and used again. A closed-loop powder management system has helped one company cut its material waste rate to less than 5%.
4. Quality reliability: from controlling things based on expertise to using data
The 3D printing process may keep an eye on important factors in real time to make sure that quality stays the same:
Watching the molten pool: High-speed cameras and infrared sensors capture data on the temperature and size of the molten pool in real time. The laser power and scanning speed are automatically adjusted. The company that prints the pipeline pieces keeps the porosity at 0.1%, which is the norm for aviation grade parts.
Detection online: Integrated ultrasonic flaw detection module that can find flaws inside the object while it is being printed. This method has helped a certain chemical pipeline raise its non-destructive testing qualification rate from 92% to 99.5%.
Following data: Every product gets its own digital ID card that keeps track of all the process data, including the powder batch, printing parameters, and post-processing technologies. This meets high certification standards like ISO 13485.
三, Use case: Disruptive practices in many fields
1. The energy sector: The lightweight revolution of high-pressure pipelines
Bimetallic composite pipes made with 3D printing can handle a lot of pressure-up to 140MPa-30% more than regular seamless steel pipes. The hollow structure design also cuts down on weight by 40% and the load on drilling platforms. After being used in a certain offshore oil field, the daily output of a single well went up by 15%, and the costs of running and maintaining it went down by 22%.
2. The chemical industry makes pipelines that are resistant to corrosion to order.
3D printing can make Hastelloy C-276 pipes that can handle strong acids and bases. These pipes are 100 times more resistant to chloride ion corrosion than 316L stainless steel. This method has helped a certain chemical company prolong the life of the reactor supporting pipeline from 3 years to 15 years, cutting down on the number of times it needs to be shut down and maintained by 80%.
3. In the medical field, making personalised pipelines with exact measurements
The 3D-printed titanium alloy vascular stent may be made to fit the patient's CT data, with an inner diameter error of no more than 0.05 mm. This solves the "size mismatch" problem that comes with regular stents. A clinical instance demonstrated that personalised stents had a 67% lower rate of restenosis than regular stents. The 1-year survival percentage of patients also went up to 98%.