Trail

Part number family

ROYCO 756 DR 55GL

LANXESS CORPORATION · HYDRAULIC FLUID,PETROLEUM BASE

One manufacturer designation, every identity it carries: 1 stock number, 5 variants in the maker's own range.

Purchasable unitnone recorded
You are here · Part numberROYCO 756 DR 55GL
Stock number →9150-01-621-8614
Specificationnone recorded

Codified — the stock numbers

The codification catalogue keys on the item of supply — each stock number opens the catalogue's own family, with approved sources and order of use.

NSN9150-01-621-8614FLIS

Also on this specification — related, not interchangeable

Other designations qualified to the same line. A different size or class on one document is a NEIGHBOUR, not a substitute — ABS5093B25 (25 mm) and ABS5093B485 (485 mm) share a specification and are not swaps for each other. Each names the line that vouches for it.

Nothing else is published on these lines yet — coverage grows with each qualified-products cycle.

The maker's own variant family — different dimension

A different variant is not a substitute unless your specification allows it. Where a variant is qualified to a specification line, its family page holds the graded, cited view; "family only" means no qualification edge is recorded.

ROYCO 756 — 5 variants · LANXESS CORPORATION · the full range →

ROYCO 756 MIL-PRF-5606 Type MIL-PRF-5606 ROYCO756 MIL-PRF-5606 ROYCO 756 DR 55GL family only ROYCO 756A family only ROYCO 756A-20L family only
Staying inside the regulation — routes from candidate to approved

Codification and qualification say who vouches for a part — they are not installation eligibility. Under EASA Part-21, eligibility flows from the approved design (type design / IPC) or an approved change; under Part-145, acceptance needs an EASA Form 1 or, for genuine standard parts, conformity traceable to the officially recognised standard (145.A.42).

  1. Classify the part. Is it a GENUINE standard part? If the IPC/CMM references only a public specification (AN/MS/NAS/SAE-AS/ISO/EN) with no OEM source-control drawing, buy at source with conformity traceable to that standard.
  2. Check for an approved alternate. The IPC/CMM/vendor list may already carry an alternate part number or vendor code — an already-approved alternate needs no new approval.
  3. Ask the design approval holder. Request the source-control data, written equivalence, or addition of the alternative source to the approved data. Document a refusal.
  4. Raise a design change. Via a Part-21J DOA (or EASA/ADOA): a 21.A.95 minor change adding the alternate to the approved data, backed by an identicality/equivalence file — dimensions, material, class, load rating, lubricant/seal, corrosion protection, acceptance criteria. Critical applications escalate to major change/STC.
  5. FAA-PMA / BASA path. Where the product is also FAA-certificated: PMA parts reach EASA aircraft under the BASA/TIP (non-critical directly; critical via EASA-validated STC).
  6. Production, release, traceability. Approved parts are produced under a POA, released on an EASA Form 1 (marked EPA where applicable), with EN/AS 9120-grade traceability into Part-145/CAMO acceptance.

Stage 1(a): we assemble the equivalence/identicality starter file — the cited evidence this graph holds, shaped for your DOA or compliance department to take forward. See pricing.

Regulatory explainer, not legal advice: paragraph numbers, derogations and the BASA/TIP revision change — verify against the current consolidated Regulation (EU) 748/2012, the EASA Easy Access Rules and the current TIP, and engage your DOA and competent authority early.

This crosswalk identifies candidate equivalents with cited evidence. It is not an airworthiness approval. Substitution decisions remain subject to your organisation’s procurement and engineering approval process and the governing maintenance data (AMM/CMM/SRM/CML/OMAT).