Overview
ISO 6485:1980 defines an internationally recognized procedure for the volumetric rating of tractor-scrapers used in earth-moving machinery. This standard provides a consistent method to approximate the volume of materials contained within the bowl of open bowl scrapers by measuring the inside dimensions and accounting for representative heaps on top of the bowl. The primary purpose of this volumetric rating method is to enable uniform comparison of scraper capacities under standardized conditions rather than to specify actual operational capacities.
Developed by ISO Technical Committee ISO/TC 127 on Earth-moving Machinery, this standard ensures that manufacturers, operators, and engineers have a reliable and repeatable procedure to assess and communicate scraper bowl volumes for design, purchasing, and operational planning.
Key Topics
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Scope and Application
ISO 6485:1980 applies exclusively to open bowl scrapers and defines how to measure the struck (inside bowl) volume and the top (heaped) volume based on fixed dimensional boundaries. It includes specifications for positioning bowls, closing aprons, and accounting for various geometric features.
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Volumetric Measurement Procedure
- Position the scraper bowl with the floor as horizontal as possible.
- Fully retract the ejector and close the apron tightly to minimize gaps.
- Define the struck volume within the interior surfaces of the apron, cutting edge, bowl floor, ejector, and sides.
- Establish boundary planes using a 1:1 slope (45°) from top apron edges and mean lines for calculating volume boundaries.
- Add the top volume by projecting planes of 45° slope above the struck volume to account for heaped soil typically retained during operation.
- Ignore local features such as gussets or apron arms in volume calculations.
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Expression of Ratings
- Volumes under 10 m³ are reported to 0.1 m³ precision.
- Larger volumes are expressed to 0.5 m³ precision.
- Published ratings must be within ±3% of volumes determined by the ISO method.
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Definitions and Components
- Defines "open bowl scraper" and key components such as the apron, ejector, cutting edge, floor, and bowl sides to standardize measurement.
Applications
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Equipment Specification and Comparison
Enables manufacturers and buyers to compare scraper bowl volumes uniformly, facilitating informed decisions when selecting earth-moving machinery for construction, mining, and civil engineering projects.
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Design and Performance Evaluation
Provides engineers and designers with standardized volumetric references for scraper bowls, aiding in optimizing load capacities, power requirements, and operational efficiency.
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Operational Planning
Helps fleet managers and contractors estimate material handling capacities of tractor-scrapers under consistent conditions for project scheduling and cost estimation.
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Regulatory and Certification Use
Serves as a reference method in procurement, certification, and compliance assessment for earth-moving machinery capacities across different countries and markets.
Related Standards
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ISO 7133: Earth-moving machinery - Tractor-scrapers - Terminology
Defines the vocabulary used in tractor-scraper equipment, complementing ISO 6485 by standardizing terms used in volumetric rating.
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ISO 6016: Earth-moving machinery - Symbols for operator controls and other displays
Relevant to operators who need clear understanding of scraper controls impacting volumetric efficiency.
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ISO 9001: Quality Management Systems
While not scraper-specific, it supports manufacturers in maintaining consistency related to standards such as ISO 6485.
Keywords: ISO 6485, tractor-scraper volumetric rating, earth-moving machinery, open bowl scraper volume, scraper capacity measurement, earth-moving equipment standards, volumetric measurement procedure, scraper bowl volume, construction machinery standards.
