ISO 1328-2:2020 Gear Accuracy Standards Update

Summary: The 1995 and 1997 ISO 1328 editions have been retired; ISO 1328-1:2013 together with ISO 1328-2:2020 now underpin acceptance for gear exports. Quotations still hinge on mapping accuracy grades among DIN 3961~3967, AGMA 2015 and GB/T 10095. With September’s Shanghai trade fair drawing nearer, requests for precision-ground gears are increasing. PinyiGear finishes ground teeth to the tolerance class stated on the drawing; cylindrical gear verification covers the module range and outside diameters stated on the drawing.

1. Market and Exhibitions: A Dense Second-Half Schedule, Rising Precision-Part Enquiries

1.1 Show Calendar

The China International Industry Fair runs in Shanghai each September and acts as the focal point for transmission-part and gear sourcing questions. Hannover Messe occupies Germany’s spring calendar; European purchasers typically commit orders after that event wraps up. Regional machinery and transmission shows cluster into the year’s latter half as well, and gearbox manufacturers alongside robotics businesses commonly open buying windows around those dates.

1.2 How Demand Is Shifting

Robot joint reducers, wind-turbine gearboxes and electric drive systems are all being specified at progressively higher accuracy grades. Harmonic reducer circular splines and flexsplines, planet gears and ring gears display a shared buying pattern: low volume per batch, strict accuracy, short lead time. Plants operating a full grinding-and-metrology chain are the natural fit. Purchase orders citing DIN 4~6 grades now represent a larger slice of business; during quotation the trio of module, pressure angle and helix angle gets fixed first, and only afterward do grade and pricing come up.

2. Standards Update: Revised ISO 1328 Moves Export Acceptance to the New Editions

2.1 ISO 1328-1:2013 and ISO 1328-2:2020 Replace Earlier Editions

Definitions plus allowable magnitudes for tooth flank deviations appear in ISO 1328-1:2013, which succeeded the 1995 text. Radial composite deviations are handled by ISO 1328-2:2020, the replacement for the 1997 text. Globally, these two documents constitute the most widely recognized accuracy foundation for gear commerce. When a drawing specifies “ISO 1328-1:2013 / ISO 1328-2:2020”, acceptance relies on the tolerances from those current editions.

2.2 Mapping Grades Across DIN, AGMA, GB and ISO

DIN 3961~3967 is the reference European buyers cite (DIN 3962 deals with pitch, profile and helix tolerances). North American purchasers use AGMA 2000-A88 Q grades, or AGMA 2015 aligned with ISO 1328, while the domestic market works to GB/T 10095. Approximate correspondence is tabulated below.

Establishing which grade system governs, before debating tolerance figures, eliminates considerable correspondence.

3. Policy and Compliance: Acceptance Basis Follows the Destination Market’s Standard System

3.1 Market-Specific Standard Systems Require a Consistent Report Basis

North American shipments are documented to AGMA; European shipments to DIN or ISO; Japanese shipments to JIS B 1702. A single production run can be described under multiple systems, but an inspection report may cite only one basis, and selecting the wrong one delays acceptance. Nailing down the customer’s acceptance standard at quotation stage is much easier than producing a supplementary report post-shipment.

3.2 Material and Heat Treatment Standards Travel Together

Gear steel selection follows GB/T 3077. Behavior of the two most frequently used grades:

• 20CrMnTi, carburized and quenched: core hardness 30~42 HRC, tensile strength not less than 1080 MPa
• 42CrMo, quenched and tempered: 269~321 HB

For export parts, the material grade is mapped to the destination market (20CrMnTi ≈ AISI 4320, 42CrMo ≈ AISI 4140), and a material certificate accompanies each consignment, reducing verification effort at customs and on the buyer’s side.

4. Technical Progress: Grinding and Inspection Parameters Continue to Rise

4.1 Grinding as the Default Operation for High-Precision Gears

Where carburizing and quenching produce hard tooth surfaces, grinding is in practice the finishing route. Gears ground to the ISO 3~5 band show surface roughness of Ra 0.2~0.4 µm; helix tolerances come from DIN 3962, with values normally applied for grades 5~7 lying in the 6~16 µm range. Gearbox noise, and the consistency with which load is shared, depend directly on grinding accuracy grade. PinyiGear grinding and batch production follow the tolerance class stated on the drawing; turning, grinding and hobbing parameters are set per the drawing and process review.

4.2 Inspection Capability Matching the Accuracy Demanded

Before dispatch, a full-item check on a gear measuring center covers profile, helix, cumulative pitch and gear runout; mating gears are then re-verified on a meshing tester. PinyiGear inspection ranges:

• Gear type Cylindrical gears: M0.5~20
  • Size limits: per the maximum outside diameter and face width stated on the customer drawing
  • Other: workpiece 300 kg
• Gear type Bevel gears: M1~16
  • Size limits: max. diameter 500 mm
  • Other: pitch cone angle 5°~90°
• Gear type Worm gear sets: M0.5~16
  • Size limits: —
  • Other: 1~6 starts

Hardness testing covers HRC 20~67, HV 10~1000, roughness Ra 0.01~20 µm. Reports are issued against the standard edition shown on the drawing; for export parts, the grade system in use must be stated explicitly.

5. Related PinyiGear Recommendations

PinyiGear serves gearbox and reducer manufacturers, robotics and automation businesses, high-end equipment OEMs and traders in precision transmission parts, providing:

• Precision ground gears: cylindrical and bevel gear module ranges and grinding accuracy per the values stated on the drawing (Precision Gear Products)
• Standards and selection support: inspection reports to DIN/ISO/AGMA/GB, KISSsoft strength verification (Gear Product Center)
• Full-item inspection: gear measuring center plus meshing tester for pairing, report delivered with the goods

Further technical material is available on the PinyiGear website, or contact the technical team.

Date: August 28, 2026 | Sources: ISO 1328, DIN 3961~3967, AGMA 2000/2015, GB/T 10095 standards