There is no single universal role that “sends” the work order. In regulated and complex manufacturing, work orders typically originate in planning systems and are dispatched through a defined process rather than by an individual acting alone.
Typical sources of work orders
In most plants, work orders are generated and released from one or more of the following:
- ERP / MRP system: Creates and releases production orders based on demand, MRP runs, and planning rules. Common in larger, multi-site organizations.
- MES (Manufacturing Execution System): Receives orders from ERP/MRP, breaks them into operations, and dispatches work to specific lines, cells, or machines.
- Standalone scheduler or planning tool: In brownfield environments, a separate planning or finite-capacity scheduling tool may generate or sequence work orders, which are then pushed to MES or sent as printed packets.
- Manual/planner-driven process: A Production Planner, Master Scheduler, or Production Control role may manually create and release work orders in the system, sometimes supplemented by spreadsheets or email.
Who is responsible for releasing or dispatching them?
The responsible function is usually one of:
- Production Planning / Master Scheduling: Owns work order creation and release timing based on capacity, material, and due dates.
- Production Control / Operations Planning: Manages day-to-day release, holds, and rescheduling of orders.
- MES / Dispatching function: Automatically dispatches work orders and operations to specific work centers or operators once they are released and preconditions are met (materials, tools, approvals).
- Cell or Area Supervisor: In some plants, the supervisor triggers release of work to the floor from a queue of pre-created orders.
In regulated environments, this is usually defined in procedures, with clear role-based permissions inside ERP/MES and audit trails of who created, modified, or released each work order.
Dependencies and constraints in regulated environments
Who can send or release a work order is constrained by:
- Approval and change control: Work orders often reference controlled routings, BOMs, and work instructions. Release typically requires that all referenced documents are approved and current.
- System integration: In a brownfield stack, orders may be created in ERP, transformed by integration middleware, and routed into MES or local systems. Failures or mismatches here can create duplicate or missing orders.
- Validation and traceability: Regulated plants require traceability of who approved what and when. Automated or interface-driven work order release must be validated and logged.
- Material and tooling readiness: Some sites block work order release until inventory, tooling, and NC programs or test sequences are verified as available and correct.
How this coexists with legacy and mixed systems
In many brownfield environments, there is a hybrid model:
- ERP creates a high-level production order.
- MES or a legacy shop-floor system splits this into operations and sends work orders or operation tickets to specific work centers.
- Supervisors or planners may still print, annotate, and manually hand out work orders where terminals are limited or systems are not fully adopted.
Full replacement of legacy work order processes (for example, moving all creation and dispatch into a new MES) can be risky and slow in aerospace-grade or similar environments, due to validation effort, integration debt, and the need to maintain continuity for long-lived programs. Many plants phase in new dispatching tools while keeping ERP as the system of record for work order creation.
What you should define explicitly
To avoid ambiguity and audit issues, your site procedures should clearly answer:
- Which system of record creates the work order (ERP, MES, or other).
- Which roles may create, modify, release, or cancel work orders, and under what conditions.
- How work orders are communicated to operators (screens, printed packets, travelers).
- How changes or rework are controlled, documented, and re-issued without breaking traceability.
Without this clarity, plants often experience misaligned priorities between planning and operations, duplicate orders, or undocumented changes, which are high-risk in regulated audits.
