The food and beverage industry is fast paced and places huge pressure on equipment. Time matters, and downtime matters even more, adding significant cost to the business. As a result, manufacturers are continually looking for processes which deliver advantage and save both time and money.

Research in the food industry shows that on many production lines, annual downtime exceeds 400 hours with a consequent knock-on effect on productivity, efficiency and profit margins. Contributing factors include intensive operations and high operating speeds and temperatures, all of which can lead to wear and tear and equipment break-down. For example, non-stick surfaces – so essential to many operations including bakeries – deteriorate with use, leading to inefficient production and increased downtime for cleaning. Equally, the use of corrosive and ‘sticky’ ingredients such as eggs, fats, vinegars and sugars can compromise equipment. At best they need constant washdown. At worst, they cause breakdown and failure. When dealing with edible products there’s also the important matter of health and safety and the need for FDA-approved solutions. To help offset these challenges, the use of specialist coatings to protect the equipment and enhance its operational performance is therefore commonplace. 

The benefits of coating

By offering wear resistance and high release – among other benefits – the use of surface coatings throughout the production cycle extends equipment service life while reducing downtime, waste and contamination. This in turn leads to higher product quality and lower unit costs. The advantages are therefore significant, and coating has a central role to play in production efficiency. But what are they key factors to consider?

When selecting a coating – and even a process for its application – a number of factors need to be considered. 

There’s the specific application challenge that needs to be solved – typically a question of corrosion or wear and tear through friction. The material to be coated is also a major factor, as are the conditions in which the equipment is operating. The presence of moving parts – and what kind – impact on the thickness of coating needed. There’s also the question of cleaning and preparing the surface as well as the curing process – all of which will vary according to the nature of the engineering challenge. Every combination of product and application type demands a specific treatment in order to fully develop the coating’s properties. Failure to get this right will compromise performance and results. 

There are also key commercial considerations, including determining objectives (e.g. reducing mean time between failure or accelerating repair times) and weighing up the cost benefits of any coating. Cost benefit is an important factor because while coatings undoubtedly prevent wear and corrosion, they also involve an up-front investment. This should be viewed in terms of the ‘total cost of ownership’ where the overall investment is balanced against the hidden costs of repairs, spares, downtime and failure, and the consequent loss of production. As an example of this, one of Surface Technology’s customers used a biscuit-cutting blade which needed replacing every two hours, forcing regular line closures. A coating developed by Surface Technology doubled the cost of the blade, but also extended its life to eight hours, with an overall 50% saving. Additionally, as the blade only needed to be changed at the end of shifts, higher production runs were achieved, along with less waste and lower cost of ingredients. As the more durable, higher-cost options more than pay for themselves in better performance and longer life, coatings can also be highly beneficial for smaller cookware items – not just large pieces of equipment.

Understanding the exact nature of the challenge is therefore key to the selection of coatings, and the best results will be achieved by engaging with the surface specialist as early as possible, preferably during the equipment design stages. 

What coatings are available? 

A wide range of surface coatings are available to food manufacturers, each designed to tackle a particular manufacturing or engineering challenge. For example, there are anti-corrosive coatings, and coatings to reduce friction and wear through abrasion, erosion, adhesion or surface fatigue. There are dry-film lubricants, non-stick ceramics and powder coating solutions, along with multi-layer and combination coatings which address numerous specific issues. Many of these coatings are patented, with unique properties developed for specific applications. For example, Surface Technology’s Armourcote 1530 is an anti-friction, reinforced, PTFE coating designed to enhance stainless steel surfaces with low level friction characteristics while also protecting against surface wear – making it a suitable solution for food applications with surface release problems.

Surface Technology is a leader in the field of applying Fluoropolymer-based (non-stick) coatings to food processing equipment such as rollers, chutes, guides and moulds. These and other ‘easy-release’ coatings provide a rapid return on investment by boosting quality, reducing scrap and driving down cleaning costs between cycles. In the case of one of Surface Technology’s customers – a major international manufacturer of baked foods – this cost benefit was measured in terms of a 90% reduction in time, and a 75% saving in cost. The company's UK production lines were regularly shutdown in order to recoat equipment that had been corroded by potato starch. Parts were sent to the US on a 12-week turnaround, causing delays and expense. Surface Technology identified an FDA approved double reinforced, high release, high wear coating with excellent non-stick properties which could be applied in the UK, cutting the 12-week turnaround to just 7 days.

In addition to the coatings themselves, there are the means of application depending on the coating and the thickness and finish required. Examples include thermal, plasma and flame spraying as well as a wide variety of plating techniques and high velocity oxygen fuel (HVOF), which provides a hard face and is especially suited to providing protection against erosive or abrasive wear, corrosion, fatigue, oxidation and high temperatures. Some of these methods require the removal of parts and a longer curing process, others can be applied quickly and in-situ. Equally, some are more suited to high value equipment, others for volume applications – and so in developing the optimal solution, it makes sense to work closely with a specialist supplier.

From coatings and applications, through to operating conditions and desired outcomes, it’s clear that many factors need to be considered. So, it’s important that your coatings supplier has a proven track-record, with easy access to in-depth technical support and advice and they should offer a broad spectrum of services and coatings to ensure you get the right solution – not just the only solution they provide.