[Posted on April 16th 2014 by Bill Stewart]
Steel catenary risers are commonly used throughout the offshore drilling industry to add to the stability of a rig in regards to the waves and depth changes. It’s important to understand the actual benefits of using steel within the risers as opposed to another material.
The characteristics of steel are significant. When steel is used, you can rely on the strong metal to last within almost any environment that you place it in, including deep sea conditions.
There are various alloys that need to be considered when you look at steel catenary risers. Much of the alloys are capable of performing in various conditions. You need to be keenly aware of what kind of waters you are going into so that you can choose a rise that will provide you with all of the benefits that you require. You don’t want a riser giving out on you because of failure to choose the best one.
You have to consider such deep sea conditions as:
- Depth of water
All of these are going to affect the performance of steel catenary risers. Just as you need to have anchor analysis, analysis needs to be conducted with the risers as well. The benefits are abundant due to the steel construction, though there are still variables that need to be calculated before you can take your rig out into the deep waters.
Once you understand the mechanics of catenary risers, it will be easier to figure out exactly what you need. You will be able to obtain help with this based upon what the analysis comes back as.
Whether you have engineers on your team or not, you have to consider what you are dealing with. You cannot take the benefits of steel for granted when you go out on a rig simply because there are other factors that are going to work against you.
Various accidents have occurred on the oil rigs because of a failure to understand the water pressure, the depths, the temperatures and other factors. Especially when there are more rigs going into deep waters and even into the Arctic, you have to figure out what that means in terms of preparing the rig – and the steel catenary risers are a big part of the equipment that you need to take with you.
When you take the time to have a significant amount of analysis run, you can have definitive numbers to help you with a rig design. You can factor in worst-case scenarios, too, so that you can make adjustments once you are out on the water if the temperature is colder or if the depths are deeper than you initially anticipated. This will ensure that you maximize on the benefits and avoid an accident or other issues.