An extract from Underwater Welding - A Welder's Mate
Wet-stick welding is one of the methods used in underwater repair and construction. As the name implies, the process is carried out with both the diver and welding electrode exposed to the water, suffice to say that all commercial wet welding operations shall be carried out by trained and certified commercial divers. In reviewing this process, one must understand the elements involved and the controlling factors, which are essential to a satisfactory outcome. For myself, the two main criteria that I would like for you to appreciate in reading this book are:
- Establishing the common criteria involved for the successful application of the process.
- Recognition of the quality levels possible.
Once you have come to appreciate these particular points, I believe you will have taken the first steps towards eliminating any old and out of date misconceptions about the application of the process and recognise its true potential.
The American Welding Societies underwater welding specification, AWS D3.6-99 (latest edition) describes the wet-welding process as one in which the diver and the welding arc are exposed to the water, without any physical barrier. This particular standard was prepared in response to the needs for a specification that would allow users of underwater welding to conveniently specify and produce welds to a predictable performance level. A consideration that has been overlooked by many. The standard has principally four categories for underwater properties and soundness requirements, namely “A”, “B”, “C” and “O”.
Since 2002 we in Britain now have our own specifications, BSEN ISO 15618-1. Entitled Qualification Testing of Welders for Underwater Welding, with part 1 covering wet welding.
To my mind, one of the difficulties one finds with the wet welding process is that it has not, until recently, been able to establish a niche, due in part to its poor early performance. In the UK this is probably due mainly to the offshore industry. Which, due to the particularly harsh environments involved has had little need for its use and has to some extent unwittingly placed wet welding into a ‘back seat” position.
A major advantage of wet-welding over hyperbaric welding, is its simplicity and low cost, with having no need for masses of expensive equipment or manpower. Although as I mentioned, the process has been around for quite some time, but it‘s only since the early 1980s that a specification was available.
Recently, however it‘s true to say there has been a greater awareness for the process, together with a willingness to take a closer look. Of course, no one will deny that wet-welds are plagued by rapid quenching from the surrounding water and do consequently suffer from lowered mechanical properties from those of surface or hyperbaric welds. However, one must take a balanced view and establish the criteria required for a given application before condemning the process outright. It is without doubt a most versatile and cost effective method of producing acceptable welds underwater, providing you understand and work within its limitations.
A misconception one often finds when discussing wet welding is people‘s interpretation of the term quality, or should I say, lack of it. This is perhaps not too surprising when you consider that it was only in 1983 that the AWS published the first recognised specification. A fact that eludes many people even today. The process is quite simply surrounded by confusion and contention. It is at times regarded as a simplistic approach, while on other occasions it can be regarded as being too complicated, with little being known of its capabilities. It would seem then, to be cheap and cheerful, yet complex at the same time. This cheap and cheerful approach regards the process as very much a temporary make do method, while on other occasions the process is burdened with complications such as welding procedures, welder qualifications and training, etc. All of which seem to be regarded as unnecessary, pointless, expensive and time consuming. It does seem to beg the question, trick or treat? Well, as with any welding process, thought must be given to the controlling factors. Without due consideration to these, it becomes clear why the process has often fallen short of the mark.
These controlling factors include:
- Proper consideration as to the process‘s capabilities.
- Sufficient thought as to its execution.
- A basic understanding of the process and performance levels.
- Availability of suitably trained and qualified personnel.
Without due consideration to these points, it becomes clear why the process has often fallen short of the mark. One of the most common pitfalls I have found when discussing wet welding, is an automatic credit system which seems to be awarded to surface or hyperbaric welders. This has directly led to many wetwelding operations being well below standard and has all to often contributed to undermining its capabilities, especially by those who would have ordinarily have considered themselves to be very capable welders.
It has been shown that without adequate training, surface or hyperbaric welders are, initially at least, in no stronger position than non-welders to carry out wet welding. Although clearly, after a basic introduction to the techniques involved can prove to be excellent wet welders.
There is clear evidence that welds produced by wet welding, which have received proper consideration are able to match desirable and predictable performance levels. I have come to recognise that on occasions there may be some confusion that exists between the term quality of weld and actual welding quality.
My interpretation is simple; weld quality is the actual examination of the weld, in relation to a code or standard. Welding quality, however, is a more encompassing criteria, which results from controlling all the relevant parameters involved in the execution and production of welding. Its aim is the achievement of a satisfactory quality of workmanship throughout.
Throughout this book you will be presented with information based upon fact and where relevant, evidence supporting the true picture of the quality levels offered by wet welding, when carried out competently. All I would ask of you whilst reading this book, is not to allow any misconceptions which you may have previously understood, dilute the evidence presented, before reaching your own conclusions. I hope you too will come to agree the process is worthy of recognition within its own right.
I have also included some information on my two latest products, namely the Hammerhead wet-spot welding process and the Swordfish non-exothermic cutting rods.