Leaf chain anchor bolts are a crucial part of a chain assembly – if they are not designed without considering all the relevant factors then they may not conform to industry standards or they may even fail. Here are the main considerations when designing an anchor bolt for use with a leaf chain.
Leaf chain is a type of chain found most commonly on telehandlers and forklift trucks. In both applications it plays a crucial role. Failure of a leaf chain component can result in catastrophic consequences – leading to a loss of production with associated financial implications or even worse, serious injuries to an operator.
Whatever the role of a leaf chain, it will inevitably wear, and this wear, if unchecked, will lead to failure. It is vital to take steps to prevent as much wear as possible and essential to monitor leaf chain wear so problems can be addressed before a major incident occurs. You should be aware that as well as measuring leaf chain wear to avoid any potential financial loss, it is also a legal requirement.
The Machinery Directive, Directive 2006/42/EC, is a European Union directive that is intended to ensure a certain level of safety in machinery and machine parts that are sold in the European Union. The directive, therefore, covers forklift trucks and other similar lifting equipment.
As leaf chain specialists we are often asked to consider how these standards and guidelines apply to leaf chains used in these types of machinery.
Some years ago, a number of forklift manufacturers started to factory-fit leaf chain with plastic guides. These guides were added to prevent wear on hydraulic cylinders or to control guide hoses which were routed through or near the mast of the forklift.
Leaf chain with plastic inserts is now available in a variety of pitch sizes and lengths and are found typically fitted to forklift trucks manufactured by Linde, Boss, Komatsu, Still, Toyota, Cesab, Hyundai and Jungheinrich.
When it comes to forklift trucks and other materials handling equipment that uses fixed leaf chains, the saying “A chain is only as strong as its weakest link” is not entirely true, as another weak point is potentially the anchor – where the chain is attached to the lift system.
A key part of that anchor assembly is the leaf chain anchor pin – sometimes called a clevis pin. They often get overlooked, but they play a key part in safely joining the leaf chain to the chain anchor bolts, therefore securing it into the lift system.
Installed and maintained correctly, the hard-working leaf chain on your forklift or telehandler will give many years of service. But any industrial chain will suffer from wear or potential environmental damage and should be periodically inspected.
To carry out a leaf chain inspection, you need to know certain facts about the chain, facts which are not discernible from a visual inspection. Knowing the part number can help, but that doesn’t tell the whole story.
A telescopic handler (telehandler) is a widely used and hugely versatile piece of equipment on a job-site.
But just like any other piece of substantial construction equipment, how well a telehandler can do its job is dependent upon the quality of its component parts.
In this blog post we describe six key industrial chain product solutions that each play a role in ensuring the safe operation, consistent performance and long service life of a telehandler boom.
Some applications like drilling rigs, piling rigs and port equipment experience very high temporary loads. These high loads are generated by the harsh environment, dirt and debris. When drilling and piling, an additional factor is the inconsistency of the ground structure that’s being worked through.
When choosing a leaf chain, you should consider a number of other factors in addition to the chain’s strength, as these factors will affect the chain’s durability.
The tensile strength of a leaf chain derives from the number of link plates which are used in the lacing, the more plates there are, the greater the tensile strength.
For example, moving from BL634 to BL644, which is just one extra link plate, will increase the tensile strength from 75.6 kN to 97.9 kN (figures from ISO 4347) a 25% increase.
The harshness of the operating environment in ports or harbours, together with the requirement for long operational shifts, can place huge demands on leaf chain.
And for empty container handlers, which are often required to stack up to eight containers high (or heights of more than 20 metres), the extreme working conditions are some of the most challenging of all.