Alignment Dowel Holes: Diameter tolerance H7/g6 fit

Component Specifications

Definition

Alignment dowel holes are precision-machined cylindrical features in end-effector mounting plates designed to accommodate hardened steel dowel pins. These holes provide exact positional reference and rotational orientation for mating components, ensuring repeatable alignment within micron-level tolerances during robotic tool change operations. The holes are typically arranged in specific geometric patterns (such as diamond or rectangular configurations) to prevent incorrect assembly and maintain coaxial alignment under dynamic loading conditions.

Working Principle

Alignment dowel holes function through interference fit or slip fit with precision-ground dowel pins. The holes provide geometric constraint in multiple degrees of freedom while allowing controlled clearance for thermal expansion and manufacturing variations. During assembly, dowel pins inserted into these holes create a kinematic coupling that precisely locates the end-effector relative to the mounting plate, eliminating cumulative tolerance stack-up and ensuring positional repeatability across multiple tool change cycles.

Materials

Typically machined into: Carbon steel (AISI 1045, 4140), Stainless steel (304, 316), Aluminum alloy (6061-T6, 7075-T6). Hardness: 30-45 HRC for steel, Anodized for aluminum. Surface finish: Ra 0.8-1.6 μm.

Technical Parameters

Parameter	Typical range	Notes & selection driver
Roundness	≤ 0.005 mm
Cylindricity	≤ 0.008 mm
Depth Tolerance	±0.1 mm
Perpendicularity	0.01 mm/100 mm
Surface Roughness	Ra 0.8 μm max
Diameter Tolerance	H7/g6 fit
Positional Tolerance	±0.02 mm

Ranges are indicative industry figures for RFQ preparation, not a supplier commitment. Confirm every value and standard with the legal manufacturer before ordering.

Standards

ISO 2768-mK, DIN 7172, ISO 286-2

Parent Products

This component is used in the following industrial products

End-Effector Mounting Plate

A structural interface plate that connects the robotic arm's wrist to various end-effectors or tools.

View Product Details

Engineering Analysis

Risks & Mitigation

Accumulated tolerance stack-up
Wear-induced clearance increase
Corrosion in harsh environments
Thermal expansion mismatch
Improper dowel pin installation

FMEA Triads

Trigger: Insufficient hardness or improper material selection
Failure: Hole wall deformation under cyclic loading
Mitigation: Use hardened steel (45-50 HRC) or apply surface treatments like nitriding

Trigger: Poor machining quality or tool wear
Failure: Excessive clearance causing positional drift
Mitigation: Implement statistical process control (SPC) and regular tool calibration

Trigger: Contamination or debris accumulation
Failure: Binding during dowel pin insertion/removal
Mitigation: Include cleaning protocols and protective covers in maintenance procedures

Industrial Ecosystem

Compatible With

Typical Suppliers & Equivalents

Compliance & Inspection

Tolerance

Positional tolerance: ±0.02 mm, Diameter tolerance: H7 (ISO 286-2), Geometrical tolerances per ISO 1101

Test Method

Coordinate Measuring Machine (CMM) verification, Go/No-Go gauge inspection, Laser interferometry for positional accuracy

Procurement Evaluation Criteria

A practical evidence checklist for RFQ preparation and supplier evaluation.

Technical documentation

Request current drawings, revision history, and a signed specification sheet.

Manufacturing capability

Verify equipment lists, process limits, capacity, and representative production evidence.

Inspection readiness

Confirm test methods, calibrated equipment, sampling plans, and traceable reports.

Supplier transparency

Check the legal entity, factory address, ownership, certifications, and direct contacts.

CNFX does not score or rank suppliers. Buyers must verify all claims and documents with the legal manufacturer before ordering.

Manufacturers of Alignment Dowel Holes

Manufacturer profiles associated with Alignment Dowel Holes.

Sourcing Alignment Dowel Holes from China?

Tell us your specification and target quantity — we will match it against manufacturer records and come back with the factories that fit.

Request manufacturers We manufacture this

Manufacturer listings support early research and capability understanding. They are not certification, ranking, or transaction guarantees.

Related Components

Chrome Plating

Hard chrome plating is an electroplating process that deposits a layer of chromium onto metal surfaces to enhance wear resistance, corrosion protection, and reduce friction for hydraulic cylinder piston rods.

Upper Tool (Punch)

Upper Tool (Punch) is the active forming component in metal plate bending machines that applies precise downward force to create bends in sheet metal.

Main Frame

The main frame is the primary structural component of a hydraulic press, providing rigidity and stability to withstand high compressive forces during metal forming operations.

Shaft Bearing

Precision component supporting rotating shafts in vibration motors to reduce friction and maintain alignment.

Frequently Asked Questions

What is the purpose of alignment dowel holes in end-effector mounting plates?

Alignment dowel holes provide precise positional and rotational reference for mating components, ensuring repeatable tool alignment during robotic tool change operations with micron-level accuracy.

What materials are commonly used for alignment dowel holes?

Common materials include carbon steel (AISI 1045, 4140), stainless steel (304, 316), and aluminum alloys (6061-T6, 7075-T6), selected based on strength, corrosion resistance, and weight requirements.

What tolerance standards apply to alignment dowel holes?

Alignment dowel holes typically follow ISO 2768-mK for general tolerances, DIN 7172 for geometrical tolerances, and ISO 286-2 for hole tolerance classes, with common fits being H7/g6 for precision applications.

Data Basis

Editorial classification, named public sources where available, and source-reviewed manufacturer records. See the editorial policy.

Preliminary Technical Classification

This page supports structured research, RFQ preparation, and supplier evaluation. It does not replace buyer-led supplier qualification, standards review, or technical approval.

Alignment Dowel Holes