With rapid advances in aerospace, automotive, and medical manufacturing, demand for complex precision machining is rising.
Amid rising demand, five-axis CNC machining has become key for high-precision, efficient manufacturing. Its advantages lie in multi-axis coordination and the ability to complete complex surface machining in a single setup.
Traditional three-axis machining struggles with complex parts having deep cavities, irregular surfaces, and precise holes.
Multiple setups increase positioning errors and reduce precision and efficiency. Pump bodies’ complex structures, deep cavities, intersecting holes, and intricate surfaces make machining difficult.
A specific pump body model (Figure 1) consists of three parts: base shell, worm gear, and upper cover.
Engineers use multi-axis machining for the base shell, as six irregular blade slots need five-axis processing.
Deep holes and five-axis angle drilling require high precision and reaming. The upper cover features a thin-walled, hollow structure with abundant curved surfaces and complex spatial angles.
The part has complex angles and tight tolerances, e.g., a 73±0.025 mm diameter, 0.015 mm parallelism, and a Ra0.8 μm roughness.
Using lightweight, easily machinable but deformation-prone 6061 aluminum alloy, this design challenges traditional clamping methods.
Despite advances, research on multi-feature pump bodies remains limited, highlighting the need for better processes and programming.
This paper utilizes UG to study the machining of five-axis pump bodies and develop end-to-end solutions.
The study addresses toolpath, coordinates, cutting, and fixtures to improve five-axis machining precision and reduce deformation.
The innovations of this paper are:
First, propose a five-axis machining method using structural feature recognition for efficient path planning.
Second, integrate the UG CAM module to optimize five-axis programming, improving efficiency and accuracy.
Third, it creates a replicable, scalable five-axis machining solution via simulation and verification.
These findings guide CNC machining of complex parts, advancing five-axis technology in high-end manufacturing.
Analysis of Pump Housing Component Structure and Technical Requirements
This version uses “Figure 1(b)” as the subject and converts the phrase into an active form. Multiple locations require five-axis rotational symmetrical machining with stringent dimensional accuracy.
Six irregular blade slots necessitate five-axis simultaneous machining, imposing specific tool edge length requirements.
Two deep cavity and four five-axis angle-controlled drilling operations require high precision and reaming.
Thus, the bottom housing requires high-precision equipment and flexible five-axis toolpaths. Engineers schedule the bottom housing for two-sided machining on Machine A.
The pump body upper cover (Figure 1a) has complex features and requires multi-axis machining. High geometric accuracy is required, with tolerances of ±0.05 mm and a surface roughness of Ra 0.8 μm.
The aluminum alloy’s poor heat dissipation, low strength, and deformation risk make machining difficult. Conventional clamping fails to meet requirements, causing low efficiency and complex processes.
Multiple operations and workstations must coordinate to complete roughing, finishing, inspection, and other stages. Optimizing machining, clamping, and programming is crucial for enhancing efficiency and quality.
Figure 1 shows a standard worm gear machined and used for assembly; its manufacturing is not analyzed.
Pump Housing Machining Process Planning
The pump assembly requires three components and standard bearings for assembly. The process analysis and optimization are as follows:
- The worm gear is a standard part used only for assembly and has been mass-produced.
- The pump housing base (Figure 2a) is the primary component, processed on high-precision equipment A.
First, perform five-axis CNC machining on the bottom surface.
Then, reassemble for five-axis machining on the front surface and leave it in place until the top cover’s inner surface is machined.
- The upper cover is scheduled for end cap internal machining on Machine B, as shown in Figure 2(b);
- After removing the internally machined upper cover, Technicians assemble it onto the pump body top using M6 bolts.
No re-centering is required; only height data needs to be set to complete all external machining processes for the upper cover part;
- After 90% of machining, secure with M5 screws, remove M6 bolts, and finish the last 10%, cutting total time to ~20 minutes (Figure 2c).
Pump Body Machining Sequence Planning
The base shell blank is 90×90×60 mm aluminum alloy, machined on a Renick dual-swing table five-axis center. First, machine the 60×60 mm bottom platform, octagonal contours, countersunk holes, and numeric markings.
Complete two cavity and four five-axis deep drilling operations, then perform reaming and chamfering. Disassemble, flip, and clamp the part with the 60×60 mm platform at the bottom.
Align the part at the bottom-center and set the coordinate system origin there. Machining covers all front-side features of the bottom shell, including six blade slots and M4 threads (Figure 3).
The upper cover blank (75×75×25 mm aluminum) is machined on a dual-swivel five-axis center (Equipment B).
Use a D12 flat-bottom end mill for roughing the upper internal and external contours. Switch to a D6 flat-bottom end mill to finish the bottom surface and walls using depth contour milling.
Drill M5 holes, tap threads, chamfer C0.5 edges, and finish internal curves with an R3 ball-nose end mill.
Total internal machining on the top cover takes about 15 minutes (Figure 4).
After machining, mount the part on Device A, measure the height for coordinate compensation, and continue (Figure 5).
After assembly, use a D12 end mill for roughing the top cover exterior, avoiding M6 bolts on the bottom wall. Use a D6 chamfer tool for M5 holes, then a D10R1 end mill to finish the external curves of the end cover.
Next, finish the six holes with a D6 flat-bottom end mill, then secure the upper cover with M5 screws. Remove the M6 bolts and perform rough and finish machining on the M6 bolt areas.
Program toolpaths carefully, chamfer the ϕ8 holes, and complete all machining of the upper cover.
Conclusion
This study demonstrates a comprehensive approach to five-axis CNC machining for complex pump body components, addressing the challenges of deep cavities, irregular surfaces, thin walls, and high-precision hole patterns.
By integrating structural feature analysis, process planning, fixture strategies, and UG-based toolpath programming, the proposed workflow ensures high positional accuracy, reduces deformation, and minimizes multiple setups.
Key achievements include unified coordinate system setup for single-setup, multi-directional machining, modular toolpath reuse to cut programming time by over 40%, and optimized five-axis finishing that reduces machining time while maintaining precision.
Flexible toolpaths, controlled tool axis orientation, and allowance management enhance surface quality and stability.
The methodology provides a replicable, scalable solution for multi-feature parts, offering theoretical and practical guidance for advancing intelligent, high-precision CNC machining in aerospace, automotive, and medical manufacturing.
FAQ:
Five-axis CNC machining enables multi-axis coordination, allowing precise machining of deep cavities, irregular surfaces, and intersecting holes in a single setup, reducing positioning errors and improving efficiency for complex pump bodies.
UG software integrates CAM modules for optimized toolpath planning, structural feature recognition, and simulation-based verification, improving programming efficiency, machining accuracy, and reducing trial-and-error during production.
Three-axis machining requires multiple setups for deep cavities and irregular surfaces, which increases positioning errors, reduces precision, and fails to meet modern manufacturing demands for high-accuracy, complex parts.
Upper covers feature thin walls, curved surfaces, complex spatial angles, and tight tolerances (e.g., ±0.05 mm, Ra0.8 μm). Combined with deformation-prone aluminum alloys, these features challenge clamping, stability, and surface quality.
By enabling simultaneous machining of six irregular blade slots, deep cavities, and angle-controlled holes, five-axis machining ensures high positional accuracy, precise reaming, and efficient single-setup processing.
Flexible five-axis toolpaths, controlled tool axis orientation, modular fixture strategies, and allowance management minimize part deformation while maintaining surface quality and dimensional accuracy.
Reusing modular toolpaths cuts programming time by over 40%, standardizes operations, reduces errors, and allows scalable machining solutions for multi-feature pump body components.
A unified coordinate system enables single-setup, multi-directional machining, ensuring consistent alignment across complex features, reducing setup errors, and improving overall precision.
Internal machining of the upper cover takes approximately 15 minutes, while careful sequencing of roughing, finishing, tapping, and chamfering ensures all features are completed efficiently without rework.
The approach provides a replicable, scalable solution for complex, high-precision parts, improving manufacturing efficiency, reducing errors, and advancing intelligent CNC machining across industries requiring multi-feature, precision components.
