CASE STUDY
CUSTOMER AND APPLICATION.
The customer that required our solution is a world leader in the manufacturer of wood fibre insulation board. Utilising production techniques that have been developed over time and are unique to their business. The principals are similar to plywood production but are unique in respect to manipulating the fibre to create the correct characteristics.
A well-established process, so not exclusive in this case, is the employment of hot ponds. The objective of which is to season the timber and make it suitably workable to facilitate conversion. The process employs a series of chain strands to carry the product through water tanks.
ORIGINAL CHAIN.
The original chain selection was a US standard welded steel chain according to B29-16. A product well known to John King Chains through their US manufacturing plant in Birmingham, Alabama.
The chain is of a robust and simple construction with a bush circumferentially welded to the cranked link plates of the chain. The chain bearing pin have substantial hot rivets for maximum tensile strength and impact resistance. John King Chains have developed uprated material and heat treatment standards to ensure that the performance of their chain surpasses all competitors.
Originally John King Chains were not selected for OEM supply. The consequence of commercial advantage overriding quality and technical considerations. The original chain installed worked for a period of time before developing substantial operational problems. The chain became solid with free movement being almost totally impaired, leading to failure.
EXPLORATORY.
The customer requested the assistance of John King Chains to understand the issues and make a recommendation for future proofing the issue.
During the site inspection a high degree of contamination in water contained in the tanks was revealed. Samples were taken and the water was subsequently analysed by a test laboratory. The water was confirmed to have a high level of polluted, but the material content although diverse was found to be relatively innocuous and not particularly high in individual contaminants. It was of an acidic nature, but not at a level where corrosion resistant materials were recommended.
It was clear that the polluted water was coating the chain (p1) and entering the critical clearances between the pin and bush, and inner and outer plates where it had solidified.
The level of contamination could be seen in the debris stripped from the chain and deposited in the return U rail (p2). This resultant seizure has proven to be profound. The cycle of emersion and subsequent drying may have proven to be more dramatic during warm summer months, although this is conjecture.
JOHN KING CHAINS PROPOSAL AND SOLUTION.
It was considered that the original chain selection was legitimate. The oversight however was the consequences of the ongoing impact of cyclic emersion into heavily contaminated water and subsequent drying on the return strand.
It was the clear opinion that by increasing the clearances within the two areas between ‘pin and bush’ and ‘inner and outer link plates’ would have a positive impact.
To achieve this the chain pitch was adjusted so that the running pitch and the gearing relationship between chain and sprockets was maintained. Oil ways were also introduced to allow for pre lubrication and periodical ongoing lubrication during service.
The lubrication chosen was from the John King Chains range of chain oils and greases type JKO1437M. This revolutionary chain oil offered all the best qualities to work effectively in a wet and hostile environment.
The hybrid welded steel chain supplied proved to be highly successful and the problem was overcome with long term trouble free running the outcome.
A pleasure to behold – John King Chains operating successfully.
We asked John King Chains to help us and they provided a solution.
We were pleased to work with a business that were able to establish the nature of the problem and deliver a permanent solution
The Chief Engineer
