Three concepts, three separate questions
The three are often confused, but they answer different questions.
- OEM number: the number given by the company that manufactures the part. Warranty and technical documents are tied to this number.
- An equivalent is a part from another manufacturer or brand that does the same job. Its size and connection fit, but its life and price may be different.
- A cross-reference is the same part being referred to by different codes: the manufacturer number, the supplier catalogue code, your own old internal code. These are not different parts, they are names of the same part.
Same card or separate card
You decide the number of cards. The cases below show the typical choices:
- Same part, different code (supplier code, old internal code) → same card. Write the old code in a field that will show up in search.
- Approved equivalent, small price difference, no warranty or safety impact → can be the same card; but the cost becomes the average of the two prices (calculation below).
- Large price difference between the equivalent and the OEM → separate card; the brand field is written differently.
- The equivalent has a short life or affects the warranty → separate card; it shows up separately in the consumption report.
- The equivalent is approved only for a specific machine group → separate card and a compatibility row only for that group.
How two prices on the same card shift the cost
In Reper Axis, if no price has been entered by hand on the work order line, consumption is posted at the card's weighted average cost. If two different brands are kept on the same card, the average works regardless of which part was fitted to the machine.
Example (the figures are assumptions): in stock there are 10 OEM filters at 1,500 TL and 10 equivalent filters at 900 TL, on the same card. The average is (10 × 1,500 + 10 × 900) ÷ 20 = 1,200 TL. When twenty filters are fitted, the total cost comes to 24,000 TL and is the same as the real total (15,000 + 9,000); but looking at the work orders one by one, the machine that got the OEM was charged 300 TL too little and the machine that got the equivalent was charged 300 TL too much. The total is right, the machine and project breakdown is wrong.
If the price difference is small, this shift may be ignored; as the difference grows, a separate card protects the cost comparison per machine.
Who decides on using an equivalent
Using an equivalent is a technical responsibility: the maintenance engineer or the workshop manager decides in writing which alternative is accepted, according to the machine type and working conditions. These four pieces of information are written in the card's note: which brand, on which machines, who approved it, on what date.
On a machine still under warranty, an equivalent part can affect the warranty; an equivalent is not fitted without the manufacturer's written condition. If an urgent need arises in the field, the person who makes the decision writes the reason in the work order note; the next day the decision is entered in the card note.
Not losing the old code in search
The mechanic usually asks for the part by the number he has memorised or by its short name. Part search scans the code, name, OEM number and barcode fields. Writing the code at the end of the part name ("... (old: HF-220)") or putting the manufacturer number in the OEM No field opens up a place for the search to find.
When selecting a part on a work order, a search made in the context of the machine brings compatible cards forward. Carry the equivalent information with the card note and the brand field.
A clean-up once a year
List the cards that have seen no movement in the last twelve months and make the unnecessary ones inactive. A card that has movements cannot be deleted, it is made inactive; this preserves the recorded history. If there are several cards doing the same job, open the Part Consumption Report by part and see which one is really used; the unused card is made inactive and the note of the remaining card is updated. For other arrangements on the stock side, see the spare parts inventory tracking guide.
