Shortening clutch Grade 100

Product Overview
Grade 100 Clevis Shortening Clutch This shortening device provides a pocket that the chain seats directly into, allowing for an in-line pull related to the chain leg. Designed to attach directly to a length of chain via the engineered clevis head which prevents hook-to-chain mismatch. Features include Grade 100 alloy steel construction, tough powder coat finish, built-in latch that prevents chain disengagement while not under load, availability of replacement parts, and proof testing and certification.

Introduction
The Grade 100 Clevis Shortening Clutch is engineered for high-performance lifting applications to allow temporary shortening of chain slings without replacing the entire assembly. It improves load control and reduces inventory needs for different sling lengths.

Heat Treatment: Optimizing Material Properties
After forging each clutch undergoes precision heat treatment (quenching and tempering) as specified in EN 818-1. Process steps: austenitizing at 850-900°C; quenching in oil or water; tempering at 400-500°C. Resulting surface hardness approximately 45-50 HRC, balancing strength and toughness.

Precision Forging: Achieving Dimensional Accuracy
Manufactured through precision forging to align grain structure with load paths, eliminate internal voids, and preserve strength. Critical dimensions are precision machined to ensure: pocket geometry accuracy ±0.01 in (±0.25 mm); clevis head dimensions ±0.005 in (±0.13 mm); latch mechanism clearances ±0.005 in (±0.13 mm).

Quality Assurance: 100% Magnaflux Inspection
Every unit undergoes 100% Magnaflux (magnetic particle) crack detection before shipment to find surface and near-surface defects. All load pins are 100% individually inspected and tested for dimensional accuracy and material properties.

Design Features That Enhance Safety and Reliability

• Pocket design: engineered pocket creates a distributed bearing surface that spreads load evenly, ensures proper chain seating, prevents chain rotation, and allows in-line pull.
• Integrated clevis head: permanently attached to the clutch body to prevent incompatibility with hooks and ensure compatibility with Grade 100 chain systems.
• Built-in latch: passive safety feature that automatically engages when chain is seated and releases when chain is lifted; requires no operator action.

Performance Characteristics

• Working load limit (WLL): ranges from 3,000 lbs (for 7/32″ chain) to 35,300 lbs (for 3/4″ chain).
• Fatigue rating: 1.5 × WLL for 20,000 cycles.
• Proof load: 2.5 × WLL, 100% tested on every unit.
• Safety factor: minimum 4:1 (minimum breaking force is 4 × WLL).
• Temperature range: -20°C to +80°C (-4°F to +176°F).
• Corrosion resistance: powder coat finish.

Recommended Applications

• Adjustable sling length: temporarily shorten chain slings for different load heights.
• Load control: improve positioning and control by adjusting sling geometry.
• Inventory optimization: reduce number of different sling lengths required.
• Retrofit: add shortening capability to existing chain slings without replacement.
• High-cycle operations and safety-critical lifting applications.

Available Sizes and Specifications (parameter table)
Chain Size | Chain Ø (in) | A (in) | B (in) | C (in) | D (in) | E (in) | F (in) | G (in) | Pin (in) | WLL (lbs) | Weight (lbs) | Part Number
7/32″-1/4″ | 0.219-0.250 | 0.31 | 0.31 | 0.39 | 0.31 | 0.75 | 1.77 | 0.91 | 0.35×0.69 | 3,000 | 0.46 | CXX06
9/32″ | 0.281 | 0.37 | 0.37 | 0.39 | 0.37 | 0.93 | 2.20 | 1.14 | 0.35×0.89 | 4,300 | 1.06 | CXX07
5/16″ | 0.313 | 0.37 | 0.37 | 0.39 | 0.37 | 0.93 | 2.20 | 1.14 | 0.39×0.89 | 5,700 | 1.06 | CXX08
3/8″ | 0.375 | 0.47 | 0.47 | 0.57 | 0.47 | 1.28 | 3.07 | 1.42 | 0.51×1.24 | 8,800 | 2.47 | CXX10
1/2″ | 0.500 | 0.61 | 0.61 | 0.71 | 0.61 | 1.73 | 3.54 | 1.38 | 0.63×1.65 | 15,000 | 4.03 | CXX13
5/8″ | 0.625 | 0.75 | 0.83 | 0.83 | 0.75 | 1.97 | 4.17 | 1.50 | 0.83×2.03 | 22,800 | 6.24 | CXX16
3/4″ | 0.750 | 0.94 | 0.93 | 0.94 | 0.94 | 2.66 | 5.24 | 1.73 | 0.94×2.42 | 35,300 | 14.88 | CXX20

Dimension Reference Guide
A: Pocket width (opening dimension); B: Pocket depth (bearing surface dimension); C: Pocket length (bearing surface length); D: Clevis head width; E: Clevis head height; F: Overall length; G: Latch projection; Pin: Pin diameter × length.

Material Specifications
Material Grade: High-tensile alloy steel (ASTM A952 Grade 100) Carbon Content: 0.35-0.45% Chromium Content: 0.5-0.8% Nickel Content: 0.3-0.6% Molybdenum Content: 0.15-0.25% Sulfur Content: ≤ 0.035% Phosphorus Content: ≤ 0.035% Surface Hardness: 45-50 HRC Tensile Strength: ≥ 1,800 MPa (260 ksi) Yield Strength: ≥ 1,400 MPa (200 ksi) Elongation: ≥ 8% Impact Toughness: ≥ 40 J (30 ft-lbs) at 0°C

Dimensional Tolerances
Pocket Width (A): ±0.01 in (±0.25 mm); Pocket Depth (B): ±0.01 in (±0.25 mm); Pocket Length (C): ±0.01 in (±0.25 mm); Clevis Head Width (D): ±0.005 in (±0.13 mm); Clevis Head Height (E): ±0.005 in (±0.13 mm); Overall Length (F): ±0.01 in (±0.25 mm); Latch Projection (G): ±0.005 in (±0.13 mm); Pin Diameter: ±0.005 in (±0.13 mm); Pin Length: ±0.01 in (±0.25 mm).

Performance Specifications
Working Load Limit: as specified per size; Proof Load: 2.5 × WLL (100% proof load tested individually); Minimum Breaking Force: 4 × WLL (4:1 safety factor); Fatigue Rating: 1.5 × WLL for 20,000 cycles; 100% Magnaflux crack detection; 100% pin inspection; Surface Finish: powder coat (blue); Temperature Range: -20°C to +80°C.

Standards and Certification
Manufactured and tested to comply with ASTM A952, EN 1677-1, EN 818-1, and DIN 17115. Certifications include material certification (mill test reports), proof load test reports, Magnaflux inspection reports, dimensional verification, and compliance documentation.

Maintenance and Replacement
Inspect before each use for visible damage, cracks, corrosion, and latch operation. Clean regularly, apply light oil in humid environments, and store dry. Replace immediately if showing damage, cracking, or permanent deformation; do not attempt repair.

Technical specifications

• Product: Grade 100 Clevis Shortening Clutch
• Material: High-tensile alloy steel (ASTM A952 Grade 100)
• Surface hardness: 45-50 HRC
• Tensile strength: ≥ 1,800 MPa
• Yield strength: ≥ 1,400 MPa
• Elongation: ≥ 8%
• Impact toughness: ≥ 40 J at 0°C
• Working load limits: 3,000 to 35,300 lbs depending on size
• Proof load: 2.5 × WLL (each unit tested)
• Minimum breaking force: 4 × WLL
• Fatigue rating: 1.5 × WLL for 20,000 cycles
• Temperature range: -20°C to +80°C
• Finish: Powder coat
• Inspections: 100% Magnaflux crack detection; 100% pin inspection
• Standards: ASTM A952, EN 1677-1, EN 818-1, DIN 17115