A stockroom full of parts and a plant that still stops for a missing item is the usual result of sourcing that grew order by order. The parts exist; the plan does not, and the gap shows up in the items nobody classified.
(Last modified date: November 12, 2026)
A sourcing map is what closes that gap. It is built in a fixed order, and this article follows that order from the wear points to the reporting that keeps the map current.
Why a sourcing map beats a parts list
A parts list records what has been bought; a map records what the plant wears, how fast, and what happens when it is not available.
That difference matters because the two documents answer different questions. A list tells a store what to reorder. A map tells a planner which items need two sources, which can be held for a season, and which are worth standardising across sites.
The map also exposes the items that nobody owns. Every plant has a few wear points that are bought ad hoc, usually by whoever notices the problem, and those are the ones that stop production when the supplier is out of stock.
Mining plant wear parts: what the map has to cover
The map covers three things.
Where the wear occurs, what it costs when it is not available, and how the item will be obtained and held.
Those three correspond to the physical plant, the operational consequence and the sourcing arrangement. Working in that order prevents the common failure where a supplier arrangement is chosen for a category of item before anybody has established how critical that category is.
The map is also the document that survives staff changes. A plant that has the wear points recorded, with their consumption and their criticality, can hand the sourcing position to a new planner; one that relies on a storekeeper’s memory cannot.
Mobile vs fixed mining plant: how wear parts sourcing differs
| Factor | Mobile plant | Fixed plant |
|---|---|---|
| Typical machines | Loaders, excavators, dozers, haul trucks, graders | Crushers, screens, chutes, conveyors, pumps |
| Typical wear parts | Teeth, adapters, cutting edges, end bits, track parts | Liners, blow bars, rotor tips, screen media, belt-cleaner blades |
| How parts are identified | OEM or aftermarket part numbers per machine model | Plant drawings, liner layouts, site-specific dimensions |
| Usual channel | Dealers and aftermarket distributors | Liner and wear-parts manufacturers, local fabricators |
| Stocking logic | Fleet-wide kits by model | Shutdown kits by plant area |
The decision path is therefore two maps, not one: mobile parts follow the machine model, fixed-plant parts follow the plant drawing. Cutting edges for mobile plant are covered in loader bucket cutting edges; carbide options for both are in tungsten carbide wear parts for mining and crushing and on the carbide inserts page.
Mapping wear points by plant area
Mapping starts with the physical plant, divided into areas that can be walked and inspected.
A working division is: extraction and loading, haulage, primary crushing, secondary and tertiary crushing, screening and conveying, stockpile and load-out, and the mobile fleet. Within each area, the wear points are listed by position rather than by part number, so the map describes the plant rather than the catalogue.
Each entry needs four facts: the position, the wear mechanism, the consumption rate and the replacement method. The last two are the ones that decide the sourcing arrangement, and they are the ones most often missing from existing records.
Consumable versus capital items
The first split on the map is between items that are consumed routinely and items that are replaced as projects.
Consumables are replaced on a cycle or on measurement: liners, tips, edges, screen panels and similar. They need a predictable supply route and a stock position. Capital wear items are major components whose replacement is planned, budgeted and often requires the plant to be stopped for a period. They need a different route: a qualified supplier, a lead time confirmed in advance and an installation plan.
Treating the two the same produces one of two failures. Consumables bought through a capital process arrive late and expensively; capital items bought as consumables are ordered without the planning the installation needs.
Criticality classification
Criticality is what decides how much effort each item is worth, and it is assessed from the consequence of not having it.
The assessment combines two questions: how much output is lost while the item is unavailable, and how quickly it can be obtained. An item that stops the plant and takes weeks to obtain is critical. An item that slows one machine and is available locally is not, whatever its price.
| Class | Consequence of unavailability | Sourcing implication |
|---|---|---|
| Critical | Plant or fleet stopped, long lead time | Two qualified sources, buffer stock, documented specification |
| Important | Reduced output, moderate lead time | One qualified source with a stated response, stock at a set level |
| Routine | Localised impact, short lead time | Consolidated ordering on a normal replenishment cycle |
| Non-critical | No immediate operational effect | Buy on requirement rather than holding stock |
The classification is the part of the map that gets argued about, and it is worth arguing about. An item placed in the wrong class either consumes capital it does not need or creates a risk nobody has planned for.
Standardising across sites
Standardisation reduces stock and simplifies purchasing, and it only works where the duty is comparable.
Two sites running similar machines on similar material can share a specification, and the benefit is a smaller stock position and simpler ordering. Two sites on different material should not, even when the machines are identical, because the wear mechanism differs and the specification that suits one will underperform on the other.
The map is what makes the decision evidence-based. Where the consumption and the failure modes of an item are recorded per site, the comparison shows whether the item is genuinely common, and where it is not, the map should say so rather than forcing a single part number on both.
Supplier base design
The supplier base follows from the criticality classes rather than from a general preference for single or multiple sourcing.
The sequence below is the order that keeps the qualification effort proportionate to the risk.
- List the critical items and qualify two sources for each.
- Qualify one source for important items, with a stated response commitment.
- Consolidate routine items onto a small number of suppliers to reduce administration.
- Keep non-critical items outside the programme entirely.
The second item is where most programmes fail in practice. A response commitment is only meaningful if it is supported by stock, capacity or a distributor arrangement, and the map should record which of those supports it.
Inventory and lead time strategy
Inventory is the other half of the sourcing decision, and it is set from consumption and lead time rather than from habit.
The position for each item is a function of how much is consumed per period and how long it takes to replace. An item with high consumption and long lead time needs stock; one with low consumption and short lead time does not, however important it is.
- Record consumption per item per period, from the plant’s own records.
- Record the replacement lead time for each source, including the realistic figure rather than the quoted one.
- Set the stock level from the two figures, and state what triggers a reorder.
- Review the levels at the start of each operating period rather than annually.
The fourth item keeps the position aligned with the plant. A stock level set for one production rate is not automatically right when the rate or the material changes.
Performance reporting
Reporting is what turns the map into a management document rather than a filing exercise.
Four measures are enough, and each points to a different action. Consumption per tonnage produced shows whether the wear rate is changing; the interval achieved per item shows whether a specification change worked; stock cover in weeks shows whether the position is funded at the right level; and the number of unplanned replacements shows whether the criticality classification is correct.
- Report consumption per tonnage for the items in the programme.
- Report the achieved interval for items where a specification was changed.
- Report stock cover in weeks by class.
- Report unplanned replacements, and review the class of any item that produces one.
The fourth measure is the one that improves the map over time. Every unplanned replacement is either a classification error or a supplier performance issue, and both are correctable once they are visible.
Where the map breaks down
Four failures account for most sourcing map problems, and none of them is a data problem.
The patterns below are worth checking against an existing plan before it is extended.
- Wear points that nobody owns, typically bought ad hoc when they fail.
- Criticality classes that were set from opinion rather than from downtime records.
- Response commitments with no stock, capacity or distributor arrangement behind them.
- Standardisation applied across sites whose duty is not comparable.
Reviewing the map each year
The map is reviewed once a year, and the review is driven by what happened rather than by the calendar.
The inputs are the four performance measures, any change in the plant or the material, and any supplier change during the year. The output is a short list of adjustments: an item reclassified, a stock level changed, a second source qualified or a specification revised.
Keeping the review short is what makes it happen. A map that is rewritten each year is a project; one that is adjusted against evidence is a document that stays current. Material and test standards that specifications can reference are published by ASTM International and the American Society of Mechanical Engineers, and equipment conventions come from SAE International with industry practice documented by the Association of Equipment Manufacturers.
How those records are kept matters as much as what they contain, since a sourcing plan is only as good as the measurements behind it; measurement practice is published by the National Institute of Standards and Technology, and model contract terms for the supply arrangements the map describes by the International Chamber of Commerce.
FAQ
How should a mine organise wear parts sourcing?
By mapping the wear points first, classifying them by criticality and consumption, and only then designing the supplier base and the inventory position around those classes. Starting from a parts list produces a stockroom rather than a plan.
What is the difference between a consumable and a capital wear item?
A consumable is consumed on a predictable cycle and is replaced as routine maintenance. A capital wear item is a major component whose replacement is planned and budgeted. They need different sourcing routes, different lead times and different approval paths.
Should all sites use the same specification?
Only where the duty is comparable. Standardising on a common item reduces stock and simplifies purchasing, and it also means some sites run a specification chosen for a different application. The map should show which items are genuinely common.
How many suppliers should a mine use for wear parts?
Enough to cover the critical items from more than one source and few enough to keep the qualification and documentation effort proportionate. Two qualified sources for critical items, with a wider base for commodity items, is the usual shape.
What should a wear parts sourcing plan measure?
Consumption per tonnage produced, the interval achieved per item, stock cover in weeks and the number of unplanned replacements. Those four show whether the plan is working, and each points to a different corrective action.
Can one supplier cover wear parts for both mobile and fixed mining plant?
Sometimes, but the parts are identified differently: mobile plant by machine part number, fixed plant by site drawing. Map both before consolidating suppliers.
Send the wear points and the consumption records you already have, and SENTHAI will help classify them and specify the items that need a qualified source.