When requesting a quotation for mechanical and piping detailing, clients often send a general arrangement and a deadline but omit the information that determines the actual drawing-office workload. A reliable estimate needs the piping systems, available design information, drawing deliverables, existing-site constraints and engineering approval responsibilities to be defined.
This practical checklist is intended for mine owners, EPCM teams, plant maintenance groups and industrial contractors preparing a mechanical or piping detailing RFQ. WOM supports piping and mechanical drawing packages from Pretoria for project teams throughout South Africa and on selected Southern African projects.
1. Define the physical workfront and discipline boundary
State whether the package covers a new pump station, plant pipework, a brownfield tie-in, mine services, equipment replacement or a modification to an existing route. Identify the start and end points of each pipe run, its relationship to equipment and structures, and the limits of the drawing-office appointment.
- Project, workfront, location and current design stage (concept, tender, issued for detail, or construction).
- Line tags, service description, nominal sizes and the approximate number of runs or spools.
- Equipment, nozzles, pipe supports, valves, instruments, access requirements and structural/civil interfaces within scope.
- Brownfield tie-in locations, isolation windows, survey information and known site constraints.
- Clear exclusions, such as pipe-stress calculations, engineering design, procurement, field verification or fabrication supervision unless separately agreed.
2. Supply the correct source drawings and specifications
A model does not resolve missing engineering decisions. State which input documents are approved, which are preliminary and who may authorise changes.
- P&IDs and line list: service, line numbers, valves, instruments, connectivity and design basis supplied by the responsible engineer.
- Equipment vendor drawings: dimensions, nozzle positions and orientations, required operating and maintenance clearances.
- Piping specifications: pipe class, material, pressure rating, fittings, branches, joints, valves and special requirements.
- Existing arrangement information: plant GAs, civil/structural backgrounds, survey data, point clouds or coordinated models where available.
- Client drawing standards: title blocks, drawing numbers, line tags, revision conventions, orthographic styles, isometric styles and report templates.
3. Agree which drawing and data outputs the workshop or site actually needs
Plant 3D can support orthographic views and material lists, while piping isometrics and their BOM formats must be configured to the project’s agreed standards. The correct output package depends on how the fabricator or installer will use the information.
| Output | What to define in the RFQ |
|---|---|
| 3D model and coordination | Model boundary, reference coordinates, agreed software/file exchange formats and clash-review responsibilities. |
| Piping general arrangements | Plans, elevations, sections, dimensions, line identification, tie-ins and access/maintenance interfaces. |
| Orthographic details | Detailed arrangements, sections, equipment connections, pipe support positions and related BOM requirements. |
| Piping isometrics | Which lines require isometrics, split rules, dimensions, weld and joint information and fabrication stage. |
| Material take-off / BOM | Pipe, fitting, flange, valve and support reporting requirements; supply responsibility and unit conventions. |
| Support and mechanical details | Details for agreed support types, pump/base arrangements, anchor interfaces and equipment installation information. |
| Issued drawing pack | PDF/DWG versions, document register, review status, revision history and final handover method. |
Confirm whether spool drawings, weld lists, cut lists or vendor-specific files are required. These are not automatically included simply because a 3D model is supplied.
4. Specify interfaces and constraints that affect the programme
For operating plants and underground workfronts, piping often intersects multiple packages. The quotation should identify which organisation supplies approved nozzle data, equipment layouts, steelwork, anchor and support design, electrical/instrumentation space reservations, and safe-access requirements.
Particularly useful inputs include known maintenance envelopes, lifting/removal paths, shaft or tunnel restrictions, work-at-height access requirements, changeover windows and expected tie-in verification. If survey information is missing, identify the point at which site verification must occur.
5. Define the review, approval and construction release process
Identify the responsible engineer, checker and client reviewers; the RFI route; required hold points; and the intended approval cycle. Set meaningful milestones by workfront, such as initial layouts, model coordination, issued GAs, detailed isometrics, materials reporting and final revision close-out.
Important: drawing-office detailing follows approved engineering criteria. Process design, pressure design, pressure testing requirements, pipe-stress design and professional engineering sign-off remain with the appropriately appointed responsible parties unless explicitly included in the contract and performed by qualified professionals.
6. Minimum information to send WOM for a piping detailing quote
- Project name, operating site and the relevant workfronts.
- Available P&IDs, line list and piping/material specifications.
- Plant or equipment GAs, nozzle drawings and existing-site reference information.
- Approximate number of lines, nominal bore range, and the required 3D/2D deliverables.
- Support, structural and civil interface responsibilities.
- Client CAD/document standards, drawing register and revision status.
- Programme, priority workfronts, review periods and site access assumptions.
Related WOM experience and services
Explore WOM’s Mechanical & Piping Detailing service or our SMPP detailing capabilities. For a relevant mining infrastructure example, review the Karowe Underground Pump Station project, which included WOM’s drawing-office contribution within the TDS Projects Group engineering team.
For a broader multidisciplinary package, use our mining and industrial SMPP detailing scope checklist.
Ready to get a price? Request a mechanical and piping detailing quotation. Send supporting P&IDs, GAs, specifications or drawing registers by email to info@wordofmouthtrading.com, quoting your project reference.