Component Grading Criteria: Reusable, Repairable & Mandatory Scrap Rules

Introduction

Once parts are fully disassembled, cleaned and inspected (including mandatory NDT screening for safety-critical items), every component must be assigned a formal grade. Component grading criteria is not a subjective judgement by workshop technicians. Under the REMAN ROAD Standard, fixed measurable criteria separate parts into three categories: Reusable, Repairable, and Mandatory Scrap.

This component grading gate sits right after NDT and dimensional verification, before reassembly. It prevents a common reman shortcut: putting fatigued, overstressed or dimensionally drifted components back into service. Consistent grading is the foundation of repeatable, auditable certified reman.

General pre-grading prerequisites

All components must complete these checks before grading decision:

• Full visual inspection for corrosion, pitting, scoring, deformation and thread damage
• Dimensional check against OEM drawing tolerances
• Mandatory NDT (MPI / UT / RT) for load-bearing, safety-critical components
• Functional testing where applicable (valves, hydraulic assemblies, injectors)
• Review of prior damage history: overload, collision, heat damage, improper prior welding

No component can be marked reusable or repairable without passing the required inspection suite.

Grade A – Reusable Component

A reusable part can be installed directly into the reman assembly, with no corrective rework, only standard cleaning.

Qualification criteria

• Dimensional measurements fall fully within OEM allowable service tolerance; no wear beyond the wear limit
• NDT inspection returns zero crack-like indications, no subsurface laminations or material discontinuities
• Surface corrosion is light, only superficial surface rust, no deep pitting that reduces wall thickness
• No evidence of overheating, discoloration from excessive heat, or prior overload deformation
• Threads, sealing surfaces, mating faces are intact; no galling, deep scoring or impact damage
• Prior repairs, if any, were completed under formal approved procedures and documented

Restrictions

Safety-critical structural and powertrain components cannot be declared reusable just because they “look fine”. NDT clearance is mandatory for frame sections, crankshafts, steering knuckles, axle housings, fifth wheel mounts and suspension brackets.

Labeling requirement

Reusable parts are marked with a traceable grade tag, linked to the VIN component log.

Grade B – Repairable Component

Repairable parts have non-conformities that can be corrected using approved engineering procedures. After rework and re-inspection, they may be reclassified as reusable.

Qualification criteria

• Deviations are limited and repairable within the component’s design envelope
• No cracks in critical load paths; only allowable defects such as minor surface pitting, shallow scoring, out-of-tolerance surface dimensions or non-critical thread damage
• Dimensional drift can be corrected by machining, metal spraying, bushing installation or approved precision welding
• Any weld repair must follow REMAN ROAD approved WPS (Welding Procedure Specification), with post-weld stress relief where required
• After repair, the component must pass full re-testing: dimensional check + repeat relevant NDT
• The repair is permanently documented, with repair location, procedure and inspector signature saved in the asset dossier

Explicit limits on repairable items

Repair is not allowed to extend design limits. You cannot build up material to compensate for deep fatigue cracks, or repair multiple clustered crack indications on high-stress zones. Repairs on crankshaft fillets, steering knuckle load zones and frame main rail tension zones carry the strictest review and require Level III NDT sign-off.

All repair work must have a formal approval record before work starts. Verbal ad-hoc field repairs are prohibited.

Grade C – Mandatory Scrap

Mandatory scrap means the component must be discarded and cannot be repaired or reused under any circumstance, regardless of workshop preference or cost pressure. This is a hard stop rule in REMAN ROAD.

Mandatory scrap triggers

• NDT detects any crack, planar discontinuity or fatigue propagation path in safety-critical load-bearing zones
• Permanent bending, twisting or plastic deformation beyond the published straightening tolerance
• Deep corrosion pitting that reduces wall thickness below the minimum design dimension
• Heat damage, overheating or thermal fatigue that alters base material metallurgy (blue/hardened zones, burnt bearing journals)
• Multiple overlapping prior unapproved weld repairs on structural components
• Cracked crankshafts, cracked steering knuckles, fractured kingpin housings
• Thread stripping or damage on high-load fastener holes that cannot be restored by approved thread repair
• Cast components with shrinkage porosity or hot tears in load paths
• Parts with evidence of repeated overload, impact or accident damage that compromises material integrity

Once marked mandatory scrap, these components are quarantined and marked to prevent accidental reintroduction into the rebuild pipeline. They are tracked in the scrap log for audit purposes.

Component-specific grading examples

• Crankshaft: Minor journal scoring within machining allowance → Repairable; fillet crack detected by MPI → Scrap
• Frame rail: Minor non-critical surface corrosion → Reusable; fatigue crack at suspension bracket interface → Scrap
• Steering knuckle: Light surface rust → Reusable; subsurface crack detected by UT → Scrap
• Axle housing: Minor external pitting, wall thickness above minimum → Reusable; twisted or cracked flange → Scrap
• Suspension hanger: Single small non-critical weld defect repairable per WPS → Repairable; multiple clustered cracks → Scrap

Post-repair re-grading rule

All repairable parts, once reworked, restart the full inspection cycle. They are not automatically approved. Repaired components must pass dimensional verification and the same NDT method that originally flagged the defect. Only after successful re-inspection can they be upgraded to Grade A Reusable. If re-inspection still fails, they move to mandatory scrap.

Traceability and record keeping for grading

Every component grading decision is logged to the vehicle VIN:

• Component part number and serial ID
• Inspection results (dimensional report, NDT report reference)
• Final grade: Reusable / Repairable / Scrap
• If repairable: WPS number, repair date, inspector
• If scrapped: scrap reason and quarantine log reference

Auditors can cross-check which parts were reused, repaired or replaced during the reman build. Missing component grading records invalidate certification.

Common grading violations prohibited under REMAN ROAD

• Upgrading a scrap component to repairable to save procurement cost
• Skipping NDT for structural parts and grading them as reusable based only on visual check
• Performing repairs without formal WPS approval
• Reusing parts that have exceeded design cycle limits, even with no visible defects
• Hiding scrap components and reintroducing them into other rebuild cores
• Failing to re-test repaired components before reassembly

Closing

Reusable, repairable and mandatory scrap grading rules create clear guardrails for component reuse in certified remanufacturing. Reusable parts meet all specifications without intervention; repairable parts may be restored under controlled, auditable engineering processes; mandatory scrap parts are permanently removed from the supply chain to eliminate latent failure risk.

This three-way classification is a core control of the REMAN ROAD Standard. It ensures that every part going back into a reman heavy truck has verified material integrity, protecting fleets from the unpredictable downtime and safety hazards caused by reckless reuse of fatigued components.