With all textiles such as nets, belts, etc., these are subject to degradation in functionality and thus in service life by the application itself. This is usually due to mechanical stress or climatic influences such as temperature, humidity or UV radiation. Knowledge of the degree of damage to high-strength textiles caused by the influences described is considered relatively insufficient.
The “ResCoTex” research project presented here has focused on load securing with lashing straps. The aim of the research project was to improve the degradation behavior of high-strength textiles for load securing using resource-saving technologies. Preferably, energy- and water-saving, UV-curing coating systems should be used for this purpose, report Petra Franitza and Marian Hierhammer from the ‘Sächsisches Textilforschungsinstitut e.V.’ (STFI) and Pieter Heyse as well as Frederik Goethals from ‘Centexbel’, Gent/Belgium. In addition, they aimed to develop suitable laboratory methods with which the material-related ageing behaviour of high-strength textiles during their life cycle can be simulated in the laboratory.
There is a good reason for focusing on load securing elements such as belts: Germany is the number one transit country in Europe. This is why transport chains of different modes of transport are often used here (combined transport). In order to avoid personal injury and/or damage to property, it is therefore also a legal requirement to secure the load during transport. Despite standardised Euro pallets and special packaging units, the variety of cargo items in terms of type, geometry, size and mass poses a challenge for safe load transport. This is why the advantages of flexible technical textiles in the form of belts, ropes and nets are used here.
Developing Laboratory Methods For Durability
In order to be able to objectively evaluate achievable effects, the research project concentrated on the development of suitable laboratory methods with which the material-related ageing behaviour of safety textiles during their life cycle can be tested and estimated.
In order to gain a better understanding of the effects in practice, a test method had to be developed which allows a very realistic investigation of mechanical parameters of lashing belts. Based on the database obtained, criteria/recommendations regarding the service life, at least for product comparisons, are to be developed in order to create an understanding for the development of innovative, safe products on the market.
Weathering must be assessed as a further factor influencing the ageing behaviour of high-strength textiles. Temperature, humidity, irrigation and above all UV radiation (opto-chemical) are parameters that can considerably reduce the performance of webbing. In order to achieve this, suitable methods, test cycles and ageing times had to be found in the development phase, which allows a graded stressing and thus an evaluation. An artificial ageing procedure (global UV tester) and a procedure for a natural ageing procedure were selected.
A global UV tester can be used for artificial ageing. Parameters such as temperature, humidity, rain and UV radiation can be varied within limits. For cyclical and graded stress these parameters and the storage time were varied.
In their article in ‘melliland Textilberichte 4/19’, the researchers summed up that both natural and artificial weathering have their advantages and disadvantages and yet both are justified. The natural variant always reproduces true conditions, whereas the artificial one always has the same conditions, which makes it easier to compare the results of different products.
The decisive argument, however, is the test time, which is the same for artificial weathering speaks. Usable results require outdoor periods of two years and more. In contrast, results can be achieved with artificial weathering after only 5-10 weeks.