Blue painted U-shaped forged steel clevis with two mounting holes per prong, isolated on a white background

Mining Chains

Round Link Double Bolt Shackle

A round link double bolt shackle designed for connecting parallel chains in mining and material handling systems. It features two outboard bolts and a padless design to maintain alignment and distribute load evenly across twin chains. Built to DIN 22253 and MT/T71-1997 standards, it connects double scraper conveyors and transfer machines in coal mines using high-alloy steel with Cr, Ni, Mo elements and multiple heat treatments for fatigue resistance and mechanical strength. Available in C level and B level strength

Material: High quality alloy steel Manufacturing standards: ISO, DIN, BS, MT, etc. Strength level: C level, B level Test
Catalogue Family: Mining Chains
Certificates: EN 10204 3.1 material test certificate on request

Upload Drawing via WhatsApp Download Mining Chains PDF

CAD files are supplied on request via WhatsApp or email rather than published for open download.

Key Benefits

What Round Link Double Bolt Shackle Gives You

Padless design maintains chain alignment and prevents misalignment under dynamic load
Two outboard bolts provide balanced load transfer across parallel chains
High-alloy steel with Cr, Ni, Mo content ensures high fatigue life and impact resistance
Multiple heat treatment processes improve mechanical properties and service life

Complies with DIN 22253 and MT/T71-1997 standards for mine conveyor chain systems
Reduces chain wear and joint failure by distributing load evenly across both chains
Suitable for high-stress environments in coal mines and heavy-duty conveyors

Application Scenarios

Where Round Link Double Bolt Shackle Is Used

Connecting twin scraper conveyors in underground coal mines where chain alignment and load balance are critical
Linking transfer machines in mining operations where dual chains carry heavy material loads
Maintaining stable chain tension in high-speed conveyor systems with repeated start-stop cycles

Replacing worn or damaged chain connectors in existing mining conveyor systems
Integrating into new mine cart connection systems requiring reliable, padless jointing

Who It Is For

Buyers This Product Is Built For

Mining equipment manufacturers building scraper conveyors and transfer machines
Coal mine operators maintaining and upgrading conveyor chain systems
Rigging and material handling suppliers sourcing mine-specific chain connectors

Industrial maintenance teams replacing failed chain joints in high-stress environments
Contractors specifying durable chain connectors for long-life mining applications

Problems It Solves

Problems This Product Removes

Chain misalignment caused by loose or missing pad plates in traditional connectors
Uneven load distribution across twin chains leading to premature wear and breakage
Connector failure under repeated dynamic loading due to low fatigue resistance

Inconsistent performance when using non-standard or non-compliant chain links
Difficulty sourcing a single supplier for both mining chains and their matching connectors
Lack of traceability and material verification in low-grade chain hardware

Technical Features

Padless round link design with two outboard bolts for balanced load transfer
High-alloy steel body with Cr, Ni, Mo elements for enhanced strength and fatigue life
Multiple heat treatment processes to improve mechanical properties
Complies with DIN 22253 and MT/T71-1997 standards for mine conveyor chains

Available in C level and B level strength ratings
Test load of 2:1 applied during production to verify structural integrity
Designed for use with double scraper conveyors and transfer machines in coal mines

Specifications

Round Link Double Bolt Shackle Specifications

Values published in the Kailipu catalogue for this item. Anything not listed is available on request.

Application	Mine cart connection, twin scraper conveyor, transfer machine
Material	High quality alloy steel with Cr Ni Mo elements
Strength Level	C level, B level
Test Load	2:1
Standards	DIN 22253, MT/T71-1997
Design Type	Round link double bolt shackle, padless
Chain Compatibility	Double-sided chains, high-strength mine circular chains

Materials

Materials And Finishes

High-alloy steel with chromium, nickel, and molybdenum for improved strength and wear resistance
Multiple heat treatment processes to enhance fatigue life and impact resistance
Steel selected for compatibility with sprockets and high-stress conveyor environments

Manufacturing Process

How This Product Is Made

1Forging of round link blanks from high-alloy steel

2Multiple heat treatment stages to achieve desired mechanical properties

3Machining of bolt holes and thread profiles

4Assembly of two outboard bolts with locking features

5Final inspection for dimensional accuracy and surface defects

6Test load application at 2:1 ratio before release

7Marking for strength level and traceability

Quality Control

Quality Control On Every Batch

Test load applied at 2:1 ratio to verify structural integrity
Dimensional tolerance check against DIN 22253 and MT/T71-1997
Visual and surface inspection for cracks or defects

Material verification through chemical composition analysis
Traceability marking for strength level and batch number
Third-party inspection accepted before shipment

Customisation

Customisation Options

Custom strength level marking for C level or B level
Private label and OEM marking available

Custom packaging configuration for bulk or retail shipment
Custom bolt finish or coating on request

Compare

How It Compares With The Alternatives

An honest read on where this pattern wins and where another one would serve you better.

Alternative	Honest Trade Off
Pad-type chain connector	The padless design eliminates the risk of pad misalignment and reduces joint wear, but requires precise chain alignment during installation
Single bolt shackle	Double bolt design provides better load balance and stability for twin chains, but is heavier and more complex to assemble
Standard carbon steel shackle	High-alloy steel version offers superior fatigue life and strength in mining environments, but at a higher material cost

Use Guide

How To Use And Inspect Round Link Double Bolt Shackle

Ensure both chains are properly aligned before connecting the shackle
Tighten both outboard bolts to the specified torque before loading
Inspect the shackle for deformation or bolt looseness after each shift or heavy use
Do not exceed the rated strength level (C or B) under dynamic or shock loading
Replace the shackle if the body shows signs of cracking or the bolts are damaged
Verify chain pitch and sprocket compatibility before installation