Are the casings of industrial fans and pump bodies suitable for metal 3D printing?

一, Technical adaptability: How metal 3D printing can get around the problems that come up in traditional production
1. Moulding of complicated shapes all at once
Fans and pump casings often need complicated shapes, like built-in flow channels, heat sinks, and installation interfaces. Traditional technologies need modular manufacture and assembly, but metal 3D printing (such as selective laser melting SLM technology) can provide integrated molding of internal flow channels and external shells through a single printing process. For instance, after 3D printing the cooling pump casing for a nuclear power plant, the flow channel system that used to need 12 parts was combined into one part. This cut the weight by 40% and the fluid resistance by 15%, and it also got rid of the risk of stress concentration that comes with traditional welding methods.
2. Improving the performance of materials
The casing needs to be able to withstand corrosion, high temperatures, and a lot of pressure in an industrial setting. Metal 3D printing may employ high-performance materials including stainless steel, nickel-based alloys, and titanium alloys. It can also increase performance and refine grains by controlling the process parameters. The tensile strength of printed parts made from Inconel 718, a nickel-based alloy, can still achieve 1000MPa at a high temperature of 650 °C. This is far higher than the 800MPa of traditional castings, which is what petrochemicals, gas turbines, and other sectors need.
3. Lightweight and Topology Optimization
Metal 3D printing can do "on-demand shaping" thanks to topology optimisation design software. For instance, one type of fan casing uses a lattice structure to occupy the area that doesn't need to support weight. This cuts the weight by 35% while keeping the stiffness. Fluid dynamics modelling also helps to improve the structure of the heat dissipation channel, which lowers the equipment's working temperature by 8 °C and raises its energy efficiency by 5%.
4. Fast iteration and making things to order
It usually takes 3 to 6 months to make a mould, but metal 3D printing can do it in just 48 to 72 hours, from design to sample. A certain company that makes pumps and valves has cut the time it takes to make the shell of a new seawater desalination pump from 90 days to 21 days using 3D printing technology. They have also been able to quickly customise different pump body specifications to meet the needs of offshore platforms and other situations.
二, Analysis of a Typical Case: The Practical Path from Laboratory to Industrialization
Case 1: A big step forward in making nuclear power main pump casings without mould
Southern Additive Technology uses heavy-duty metal 3D printing to make the main pump casing for a nuclear power station that will produce a million kilowatts of electricity. The old way of doing things takes 180 tonnes of steel ingots and puts them through several forging and heat treatment steps, which can take up to six months. 3D printing, on the other hand, makes 50-ton parts directly with one machine, cutting the cycle time down to 50 days and increasing the use of materials from 15% to 95%. The printed parts passed tests for tensile strength, impact toughness, and other measures. They were better than the forgings and met the specifications for nuclear safety level one equipment.
The "Intelligent Manufacturing" Revolution of Ship Propulsion Pumps is Case 2：The Huazhong University of Science and method team created the "Micro Casting Forging" 3D printing method, which effectively makes the casing of a big ship pump jet thruster by combining metal casting and forging processes. This technology gets beyond the problems that standard methods have with equipment size. It makes components 30% stronger, increases production accuracy from 0.5mm to 0.1mm, and gets rid of all defects like pores and cracks. Right now, relevant technologies have been used on domestic aircraft carriers, LNG carriers, and other major national equipment.
Case 3: "Rapid customisation" of pumps for oil drilling
Master Drilling, a South African company that makes mining equipment, needs to quickly repair the planetary gear set solar gear on the drilling rig. A standard casting technique would take three months to deliver. With Desktop Metal's Studio 3D printing system, the printing, degreasing, sintering, and heat treatment of gears can be done in just three weeks using metal powder technology that sprays glue. The gear's surface hardness goes up to 64 HRC after plasma nitriding, which is much harder than the 45 HRC of parts that are forged in the usual way. The cost goes down by 60% and the delivery time goes down by 80% at the same time.
三, Trends and problems in the industry: from validating technology to using it on a large scale
1. Growth of the Material System
Right now, metal 3D printing materials include common industrial materials including stainless steel, aluminium alloys, titanium alloys, nickel-based alloys, and more. They are slowly adding new materials like high-entropy alloys and amorphous alloys. For instance, a company has created a high-entropy alloy for 3D printing that is 200% more resistant to oxidation at a high temperature of 600 °C than standard nickel-based alloys. This alloy can be used in very harsh conditions, like turbine discs in aviation engines.
2. A big step forward in multi-material printing technology
Gradient transition or composite printing of multiple metal materials is possible with directed energy deposition (DED) technology. A rocket nozzle, for instance, has an inside aluminium bronze cooling channel and an exterior Inconel 625 heat-resistant coating. The thermal conductivity is enhanced by 40% and the material strength reaches 1200 MPa, which meets the thermal protection needs of spacecraft. This is done by printing in layers and heating the material.
3. Making the quality control system more consistent and better
The quality traceability, process monitoring, and non-destructive testing methods for metal 3D printing are getting better and better thanks to the emergence of standards like API 20T and ISO/ASTM 52900. For instance, a company has created a machine vision fault detection system that can find problems in real time, such as powder agglomeration and an unstable melt pool during the printing process. This system can also improve the accuracy of defect recognition to 99.5%, which ensures quality for large-scale production.
4. More competitive prices
The cost of buying metal 3D printers has gone down by more than 50% since Bolite and Huashu High tech started making them in the US. At the same time, optimising the powder recycling process (for example, by utilising an inert gas circulation system) can cut material costs by 30%. When the batch size is more than 500 pieces, the total cost of 3D printing small, complicated pump body casings is about the same as that of traditional methods, according to calculations.