1. Can they be purchased separately?
Is it possible to purchase them separately? Industry practice shows that non-standard assembly line modules can indeed be purchased individually, provided that interface standards are met. The advantage of modular design lies in unified interface standards—covering mechanical interfaces, electrical interfaces, and communication protocols—which break down supplier barriers.
Enterprises can select modules from different manufacturers based on cost-effectiveness (e.g., a conveyor module from Vendor A, a processing module from Vendor B, and an inspection module from Vendor C) and achieve seamless integration as long as they comply with the standards. Examples include: frame mounting hole spacing standardized at 50mm (aluminum profile standard); a tolerance of ±0.1mm between the functional module’s bottom locating pins and the frame’s mounting holes; unified 24V DC power supply and fixed pin assignments for aviation connectors (Pin 1: Power, Pin 2: Ground, Pin 3: “In-Position” signal); and standardized pneumatic tubing specifications. Separate procurement is feasible precisely because of these unified interface standards, rather than simply buying components haphazardly.
2.
How much can be saved?
How much can be saved by purchasing separately?
Industry comparisons highlight the cost advantages of purchasing modules individually: Ball screw modules—modular ball screw units are cheaper and have more transparent pricing than those found in complete machinery (e.g., a KK ball screw module—featuring an integrated screw and guide rail with ±0.01mm repeatability—can be acquired for just a few hundred yuan); Bus modules—bulk purchasing EtherCAT bus modules directly from the source factory costs as little as 18 yuan each, offering a clear supply chain advantage; Import substitution—domestic bus modules are directly compatible with Mitsubishi and Fanuc CNC machine tools without requiring cabinet modifications; Custom solutions—going through intermediaries for non-standard linear stage customization adds a 30% to 50% markup (for technical packaging/service fees), whereas direct sourcing from the factory eliminates this middleman margin; Labor savings—point-control bus control boxes cost only a few dozen yuan, and a single communication cable connecting to the PLC can control 64 solenoid valves, resulting in faster assembly and fewer potential points of failure—purchasing individually saves on middleman margins and integration premiums, provided you have the expertise to select the right components and handle the integration yourself.
III.
Assembly Risks
Risks associated with self-assembly.
Industry analysis identifies four potential pitfalls when assembling systems from multiple suppliers: Compatibility—when robots, vision systems, and conveyors come from different manufacturers, your engineering team is responsible for ensuring compatibility across mechanical interfaces, communication protocols, and software environments, as components from different suppliers have not been pre-verified to work together; Interface coordination—while a single manufacturer would coordinate its own interfaces, there is no one to manage the gaps between components from multiple vendors; Responsibility vacuum—issues regarding adaptation, compatibility, debugging, or malfunctions require repeated communication and potential disputes with multiple parties; Hidden costs—sourcing modules from Supplier A, linear stages from Supplier B, and electrical controls from Supplier C leads to hidden costs (coordination, debugging, rework) that often consume the savings gained from the lower purchase price—while individual purchasing does save money, one must carefully calculate whether those savings are sufficient to cover the integration costs.
IV.
Integration Responsibility
Who is responsible for integration?
Based on industry experience, separate procurement requires a clearly designated integration lead—whether an internal engineering team or an outsourced integrator—responsible for the entire lifecycle, including mechanics, electrical systems, controls, application, and maintenance. Key duties include interface coordination, system-level diagnostics, error correction management, and defining the acceptance process; a single named entity must be accountable for the integration architecture. This contrasts with a turnkey whole-line solution (single integrator), where interface management, acceptance standards, and handover deliverables are handled by one party, versus a multi-vendor assembly approach, where the manufacturer must coordinate interfaces and manage design changes themselves. Three indicators of integration capability are: delivery track record for similar processes, maturity of the process package, and clarity of acceptance standards. Regarding budget, the integration lead must control the integration setup budget; separate procurement without a designated integration lead effectively means outsourcing the engineers’ work to oneself.
V.
How to Choose
When should you opt for separate procurement versus a turnkey whole-line solution?
Industry recommendations suggest the following: Choose separate procurement if you have an in-house automation team (covering mechanics, electrical, controls, and maintenance), use off-the-shelf standard modules (e.g., ball screw modules, conveyor modules, bus modules), utilize standardized interfaces, and plan to handle future modifications or upgrades yourself. Choose a turnkey whole-line solution if you lack an integration team, face tight deadlines (requiring strict adherence to acceptance and commissioning schedules), deal with complex processes (involving vision systems, robotics, and cross-platform PLC integration), or wish to avoid disputes over accountability (preferring a single entity to take full responsibility for resolving issues). Consider the long-term perspective: while discrete components (like individual relays) may appear cheaper upfront, custom-integrated PCB modules offer fewer failures and less downtime in the long run, saving time and effort on maintenance. For flexible expansion, modular production lines allow for the free combination of standard modules (e.g., capacities of 300, 600, 1200, or 2400 kg/h) and capacity scaling based on sales demand. In short: choose a turnkey line if you lack an internal team, and choose modular components if you have the team—tailor the choice to your capabilities.
Conclusion
Can non-standard assembly line modules be purchased individually? The verdict is “Yes, provided there are standardized interfaces and a designated integration lead.” Feasibility: With unified interface standards—such as 50mm aluminum profile hole spacing, ±0.1mm positioning tolerances, 24V power supply, fixed aviation connector pinouts, and standardized pneumatic lines—equipment from different sources (e.g., a conveyor from Factory A, a processing unit from Factory B, and an inspection module from Factory C) can integrate seamlessly. Cost Savings: Modular ball-screw modules cost just a few hundred yuan, and bus modules from the source factory are as low as 18 yuan; domestic alternatives replace imports without cabinet modifications, and direct sourcing eliminates 30%–50% in intermediary markups. Risks: Issues include compatibility across multiple vendors, interface gaps, accountability vacuums, and hidden costs associated with decentralized purchasing. Integration: A clear integration lead (either an internal team or an external contractor) is essential to manage mechanical, electrical, and control systems, as well as interface coordination, system diagnostics, and acceptance testing. Selection: If you have an automation team and standardized interfaces, opt for individual module procurement; if you lack a team, face tight deadlines, or have complex processes, choose a turnkey solution for the entire line.
Industry experience shows that individual procurement tests integration capabilities rather than just cost-saving skills: when interface standards are unified and an integration lead is clearly defined, modular procurement is a powerful tool for cost reduction;
however, if either element is missing, any initial savings will likely be lost during on-site commissioning.
