International manufacturer Roxtec designs and manufactures pipe and cable safety seals for a range of industries including maritime and shipping. One new product Roxtec has developed, following feedback from the shipbuilding industry, is its SPM seal. Here Roxtec UK’s marine and offshore director John Kayes discusses how the Roxtec SPM seal is already dramatically speeding up installation time and slashing costs in shipyards, while also ensuring the safety of ships and crew.
The big challenge when running pipes or cables through a fireproof or watertight bulkhead is to make a secure seal. Traditionally, the only fool-proof way was to insert the pipe into a tight-fitting and then weld it to the bulkhead itself. This proved a time-consuming operation with all the risks of high-temperature welding in a confined environment. The process was equally difficult to reverse should the pipe need replacing. After receiving a lot of feedback from its customers, Roxtec has developed a much quicker and easier solution which has not only dramatically reduced installation times, but also enhanced the safety of the through-bulkhead seal.
The product is the Roxtec SPM seal and is a remarkably simple device that holds the pipe in place by use of a metal and rubber sandwich. No welding is required. A gasket of EPDM (Ethylene Propylene Diene Monomer) rubber is held between two flanges of marine grade 316 stainless steel. The seal is slid over the end of the pipe, then the pipe is pushed into an oversized aperture on the bulkhead. The SPM seal slides forward to fill the aperture, and then a series of bolts are tightened to distort the gasket to form an interference fit. Full tightness is indicated when the blue-coloured rubber is squeezed through a set of inspection holes.
The comparatively low cost and simplicity of the Roxtec SPM seal is making the product very successful. For example, a recent notable order was for the £200m polar research ship RRS Sir David Attenborough, where specialist safety seals were installed in key areas including the engine room, power generators and external lighting. Here they will provide protection from multiple hazards. Meanwhile, Roxtec continues to push forward with an extensive range of new products and practices to help to speed up the installation of pipes and cables.
“We are very responsive to customer feedback,” said John Kayes, Marine and Offshore Director for Roxtec UK. “The SPM seal, for example, came about as a request from a major Italian shipbuilder. They had originally been using an earlier type of seal but they asked if the fitting process could be accelerated even further. This led our Swedish-based R&D team to look more closely at the design of the single pipe seal solution and develop the SPM version.”
Mr Kayes said the new seal is proving ideal, as it slashes costly man-hours, especially during scheduled maintenance stops where time is money.
“A key innovation of the SPM seal is how it removes the need for welding,” he said. “All you need to do is cut a circular hole in the bulkhead to a prescribed diameter, clean it up, remove and sharp edges and you are good to go. The opening can even be slightly irregular as there is sufficient flex in the gasket. This greatly simplifies installation, maintenance work and even repairs at sea. As an example, by switching from traditional techniques to the SPM seal, engineers at a Brazilian shipyard recently cut installation time by a remarkable 88 per cent, slashing installation costs by a half.”
Mr Kayes describes another project, in which an A-60 fire bulkhead required more than 100 penetrations with a high degree of complexity. A job that had been assessed as requiring five people, including a painter, a total of 100 hours using welding techniques was reduced to just two people and 12 hours using SPM seals.
Looking ahead
Mr Kayes said Roxtec’s approach is rooted in innovation and one key area is the fire-resistance of its products. He said Roxtec recently completed work on a brand-new fire test facility at its headquarters in Karlskrona, Sweden.
“The new lab allows a test object such as part of a bulkhead to be built and then put through a series of realistic scenarios,” he said. “The data is captured by advanced diagnostics. As a bonus, visitors and classification societies can be invited to witness the tests from an observation room.”
Another key innovation is the new Roxtec Transit Registry, a digital resource that logs all the onboard pipe and cable penetrations to allow the customer to keep track of them.
“The registry is an innovation we offer as part of our package of safety services,” he said. “It enables systemised control of the quality of all transit installations, from initial installations to the latest upgrades and additions. You can see an overview and precise locations of all the pipe and electrical penetrations on board and find all the documents and logged activities for each one. Everything you need is in one easily accessed system.”
Roxtec’s products are found widely in the commercial and naval sector vessels worldwide (see: Roxtec naval). Its cable and pipe seals are used to protect ships and people from multiple hazards including fire, flooding, the risk of explosion and electromagnetic disturbances. Key benefits include durability, reliability and flexibility. Meanwhile, in the offshore sector Roxtec’s seals are an industry standard and are used in a broad range of oil and gas infrastructure, in some of the biggest projects in the world, including on drill ships, FPSOs, jack-up rigs, offshore support vessels and semi-submersible rigs.
