Silo and Gaylord Tracking

This topic is part of the SG Systems Global bulk material, plastics resin and ingredient traceability glossary.

Updated December 2025 • Bulk Storage Traceability, ERP/MES/WMS Integration • Plastic & Resin, Ingredients & Dry Mixes, Food, Chemicals

Silo and Gaylord tracking is the controlled, system-based traceability of bulk materials from intake containers (trucks, railcars, big bags) into storage silos, then out again into day bins, blenders, presses or mixers – including any interim Gaylords, IBCs or totes. Instead of a silo being treated as an anonymous “white pipe” and Gaylords as generic boxes on the floor, each movement is recorded and linked to specific material lot assignments, batch-to-bin traceability, warehouse locations and production orders in MES and WMS.

“If you can’t answer ‘which lots are actually in silo 3 right now and what did they ship in?’, you don’t have bulk storage – you have a very large, very opaque mystery hopper.”

1) What Silo and Gaylord Tracking Actually Means

Silo and Gaylord tracking is the structured proof that:

• Every bulk truck, railcar, big bag or pallet of bags is uniquely identified and linked to a supplier lot.
• Transfers into silos are recorded with source lot(s), quantities, timestamps and destination silo IDs.
• Draw-offs from silos to day bins, Gaylords, IBCs or lines are tracked to specific orders or batches.
• Gaylords / totes are not generic – each has a unique ID, location and content lot history in the system.

It is not just writing “resin delivered to silo 2” on a clipboard. It uses barcodes, automation and materials consumption recording to tie the physical flow of powder, pellets or liquids to a coherent digital genealogy that can be queried when something goes wrong.

2) Why Silo and Gaylord Tracking Matters

In bulk-material plants – plastics, milling, dairy, chemicals – silos and Gaylords are often the biggest blind spot in traceability. Without Silo and Gaylord tracking, typical problems include:

• Wide recall scopes because you cannot tell which supplier lots were still in a silo when a defect was discovered.
• Inability to link field complaints back to specific resin, flour, sugar or chemical deliveries.
• Arguments between operations, purchasing and QA over “what was actually in the bin” last week.
• Overly conservative quarantines because the safest answer is “hold everything touched by that silo.”

Regulators, brand owners and major retailers increasingly expect credible end-to-end lot genealogy. If the story falls apart at the first silo or Gaylord, the rest of the traceability narrative will not be trusted either.

3) Relationship to Intake, Bin and Line-Level Traceability

Silo and Gaylord tracking sits between intake traceability and line-level consumption:

• Intake: GS1-128 raw material intake labelling and receiving checks create the initial lot records.
• Silos / bulk storage: Material is transferred into storage silos or tanks, often mixing multiple deliveries and lots.
• Gaylords / day bins: Material is staged in intermediate containers for molding, blending or dosing.
• Lines / batches: Material is consumed on specific work orders and recorded via consumption recording or loss-in-weight feeders.

Good Silo and Gaylord tracking makes these layers coherent. It closes the gap between “we know what the supplier sent” and “we know what each line actually ran.” Without it, silo and day-bin behaviour becomes guesswork, particularly during changeovers and partial empties.

4) Core Building Blocks – IDs, Sensors, WMS/MES and SOPs

Effective Silo and Gaylord tracking normally includes:

• Unique IDs: Clear IDs for silos, tanks, Gaylords, totes and key transfer routes.
• Sensors / signals: Level, weigh cells or flow meters feeding basic movement data into SCADA or data historians.
• WMS/MES logic: Rules for which lots can be loaded into which silo, and how usage is allocated to jobs.
• SOPs: Procedures for loading, changeovers, purges and cleaning, aligned with the system logic.

Without these building blocks, attempts at Silo and Gaylord tracking tend to degenerate into spreadsheet patches and heroic memory – neither of which holds up during recalls, audits or staff turnover.

5) What Needs to Be Tracked – In, Within and Out of Silos

A realistic Silo and Gaylord tracking regime covers three directions of movement:

• Into silos: Which truck/bag lots were loaded, how much, when and via which intake points.
• Within silos: How lots may be layered, mixed or displaced over time, including residual “heels”.
• Out of silos: Where material goes – to which Gaylords, day bins, lines or batches – and in what sequence.

The aim is not to reach perfect mathematical purity; bulk systems are inherently messy. The aim is to have a defensible model of which supplier lots could plausibly have contributed to which finished lots, not just “everything since the last full empty and clean.”

6) Silo and Gaylord Tracking in Plastics & Resin

In plastics and resin handling, Silo and Gaylord tracking often focuses on:

• Linking resin lots, masterbatch lots and additive lots to specific silos and Gaylords.
• Distinguishing between different resin grades, melt flows, colors and regulator statuses (e.g. medical, food contact).
• Tracking transfers to IBCs and drums for drying, conditioning or dedicated runs.
• Feeding accurate lot information into BMR, DHR and customer-specific traceability reports.

Because resin issues can surface late – warpage, stress cracking, contamination – being able to reconstruct “which resin lots flowed through silo A into press 14 that day” is critical for targeted containment and credible root cause analysis.

7) Gaylords, Totes and Day Bins – Not Just ‘Overflow’

Gaylords and totes are often treated informally: “extra resin from silo 3” or “line clean-out.” For traceability, that is not good enough. Robust Silo and Gaylord tracking treats them as:

• Individually identifiable containers: Each Gaylord or tote has a unique ID and barcode.
• With content history: Source silo, lots, dates and any mixing or top-off events are recorded.
• With location control: Their positions in the plant (staging, drying, line-side) are managed in WMS.

When a problem emerges, the question is not “where did we have Gaylords yesterday?”, but “which Gaylords with which lots fed which jobs, and where are the remnants now?” That is only answerable if Gaylords are part of the same traceability model as silos and lines, not an afterthought.

8) Roles & Responsibilities – Receiving, Operations, QA, Planning

Silo and Gaylord tracking cuts across several teams:

• Receiving / warehouse: Scan and create intake lots, assign them to silos or Gaylords correctly and apply labels.
• Operations: Follow SOPs for loading, changeovers and purges, and confirm movements in MES/WMS.
• QA / food safety / regulatory: Define risk-based rules – which products can share silos and which require segregation.
• Planning / scheduling: Sequence usage to minimise mixing complexity and unnecessary residuals.

When everyone assumes that “somebody else” is updating silo and Gaylord records, nobody does. Clear ownership and simple, enforceable workflows are non-negotiable if the data is to be relied upon during incidents and recalls.

9) Integration with ERP, MES, WMS, SCADA and Historian

In a connected plant, Silo and Gaylord tracking is spread across multiple systems:

• ERP: Holds supplier information, material masters and purchase orders.
• WMS: Manages physical locations, Gaylord IDs and bin and zone topology.
• MES: Links silo and Gaylord usage to work orders, batches and lines via consumption recording.
• SCADA / historian: Captures levels, flow, alarms and sometimes quality-relevant parameters like temperature and humidity.

The goal is that these systems share a consistent view of “what is where.” When ERP, WMS, MES and the physical silos disagree, traceability will default to the most pessimistic assumption – everything that might have been affected is treated as affected, even if most of it was never actually in the problem silo or Gaylord.

10) Silo and Gaylord Tracking for Recalls and Investigations

When a material-related issue emerges – contamination, wrong grade, off-spec performance – Silo and Gaylord tracking directly influences the scale of the response:

• Clear history allows you to define a focussed recall window, limited to batches actually fed by the affected silo/Gaylords.
• Weak or missing records force “global” holds and recalls that are more disruptive and expensive.
• Good genealogy allows you to approach suppliers with precise data on which deliveries caused downstream effects.

Regulators and customers care less about rhetorical commitments to traceability and more about whether you can pull up – quickly – a cohesive, time-stamped picture of how suspect material moved through your silos, Gaylords and lines into finished lots.

11) KPIs and Continuous Improvement for Silo and Gaylord Tracking

You can measure the strength of Silo and Gaylord tracking using KPIs such as:

• Percentage of bulk loads accurately assigned to silos with correct lot IDs.
• Number of “unknown” or “unassigned” consumption events from silos in MES/WMS.
• Frequency of discrepancies between silo inventory in the system and physical levels.
• Recall scope size (lots, time windows) before vs after improvements in tracking.
• Number of deviations or audit findings tied to bulk storage and Gaylord handling.

These metrics help distinguish between plants that simply have silos and big bags, and plants that use them as controlled, traceable inventory locations within a wider QMS and MES environment.

12) Common Failure Modes and Red Flags

Weak Silo and Gaylord tracking tends to leave visible clues:

• Silos treated as generic capacity – operators cannot say which materials or lots they contain at any given time.
• Gaylords labelled “regrind” or “resin” with no lot, source or date information.
• Ad hoc top-ups of silos and Gaylords with no system updates or segregation checks.
• Large, frequent inventory adjustments on bulk materials with no clear explanations.
• Investigations that conclude with “we can’t be sure what was in that silo at the time.”

Auditors, customers and regulators recognise these patterns instantly. They suggest that bulk storage is being run as an operational convenience, not as a controlled part of the traceability chain, and they often correlate with broader weaknesses in intake, contamination control and changeover management.

13) Links to Flowability, Bridging and Process Reliability

Silo and Gaylord tracking intersects with the physics of bulk handling:

• Flow problems such as silo rat-holing and bridging can leave old material trapped for long periods.
• Dust, fines and segregation effects described by powder flowability index and particle distribution can cause non-uniform withdrawals.
• Conditioning via temperature and humidity control may change material properties over time.

Good Silo and Gaylord tracking does not make these challenges disappear, but it ensures that when flow issues create quality or safety risks, you have the data to identify which lots and time windows were potentially affected – and which were not.

14) Digitalisation & Industry 4.0 – Sensors and Models

In an Industry 4.0 environment, Silo and Gaylord tracking can be enhanced with:

• Continuous level measurement and mass-balance models to approximate lot percentages in each silo over time.
• Automated updates to WMS/MES whenever valves, diverters or load-out points are switched.
• Dashboards showing “what is in each silo now” with lot, grade and supplier information.

But digitalisation amplifies fundamentals: automating a confused or informal manual process simply produces a faster, prettier version of the same ambiguity. The foundation remains clear silo IDs, simple rules, disciplined data capture and alignment between SOPs and the system logic.

15) FAQ

Q1. Do we really need full Silo and Gaylord tracking for low-risk materials?
A risk-based approach is acceptable, but even “low-risk” materials can cause major disruption when off-spec or contaminated. At minimum, you should know which supplier lots are in which silos and Gaylords at any given time and where that material was used. The level of detail and automation can be scaled to risk and cost, but having no structured tracking at all is hard to defend in audits and recalls.

Q2. Is it realistic to know exact percentages of each lot in a silo?
Not perfectly. Most sites use reasonable models based on level, density and filling/emptying patterns. The goal is not mathematical perfection; it is a defensible, documented method that lets you identify a credible set of affected lots for any recall or deviation. Being explicit about the assumptions in your silo model is better than pretending the silo is either “pure” or “unknowable.”

Q3. How does Silo and Gaylord tracking interact with regrind and returns?
Regrind and returned material should be treated as lots in their own right, with clear IDs, sources and usage rules. If regrind is reintroduced into silos or Gaylords, those movements must be captured in the same genealogy. Otherwise, regrind streams can quietly break traceability and complicate root cause analysis when defects are traced back to material history.

Q4. Where should we start if we currently treat silos as ‘black boxes’?
A practical starting point is to focus on one high-impact material (for example, a critical resin grade or allergen-bearing ingredient) and one or two silos. Introduce simple intake scanning, silo IDs, basic usage rules and a manual or semi-automatic method to allocate usage to jobs. Once that model works, expand to more silos, more materials and deeper integration with MES, WMS and SCADA.

Q5. Does Silo and Gaylord tracking always require new hardware?
Not always. Many improvements can be made using existing level sensors, manual confirmations and better workflows in WMS and MES. Over time, additional instrumentation – weigh cells, flow meters, valve position feedback – can refine the model and reduce manual steps. The critical change is usually procedural and system design, not hardware alone.

Related Reading
• Bulk Handling & Flow: Silo Rat-Holing and Bridging | Powder Flowability Index | Fines and Coarse Particle Distribution | Powder Conditioning – Temperature & Humidity Control
• Traceability & Inventory: Material Lot Assignment | Batch-to-Bin Traceability | Warehouse Locations, Bin & Zone Topology | Traceability & End-to-End Lot Genealogy | Batch & Lot Traceability for CPG Manufacturing
• Systems & Governance: Warehouse Management System (WMS) | MES – Manufacturing Execution System | Manufacturing Data Historian | Quality Management System (QMS) | Deviation / Nonconformance (NC) | CAPA