STI News

MPACT® Pipe & Cable System – Installation & Spacing

Written by STI Firestop | Dec 07, 2023

Our MPACT® Pipe and Cable System is the fastest and most flexible fire and watertight sealing system for pipe and cable penetrations through fire-rated bulkheads and decks. It is easy to install and consists of a noncombustible filler blanket,  which packs easily between penetrants, and our MFS Sealant, which bonds well to marine divisions and other substrates. The system is installed within sleeves and can bridge large gaps with no pipes or cables.  This is due to how well the MFS, an advanced Hybrid Polymer Sealant, bonds to the noncombustible filler blanket.  Small gaps are also not an issue. We typically suggest a minimum spacing of 6mm (1/4 inch), to ensure that the sealant can be quickly and easily installed continuously around each cable or pipe.  This distance helps ensure that you can get the tip of the sealant cartridge nozzle into the space and seal around each individual cable or pipe.  A minimum 12.7mm (1/2 inch) thickness of sealant is required and this minimum gap increases the likelihood that the appropriate depth of sealant is installed promoting a good bond at the points of adhesion to the cables, pipes and sleeve.  That being said, this 6mm (1/4 inch) spacing is only intended as a guide to help ensure that the material is installed properly, quickly and easily.  Smaller spacing, such as 5 mm (or even less), is acceptable just as long as the filler blanket and sealant are installed properly.  It may not be as easy or quick to install the materials in these smaller gaps, but it would be no more critical from a fire resistance perspective. This would also be considered less critical from a water-tightness perspective, provided that there is a good bond, because the span between the cables or pipes is smaller.

Figure 1 – Small gap between a large steel pipe and the edge of a sleeve

 

Figure 2 – Large gaps between cables and sleeve

It is always suggested that all surfaces be cleaned and be free of any bond-breaking contaminants and loose materials.  Although it is not required, it is suggested that a light spray of water be applied over the filler blanket to enhance the adhesion and accelerate the curing process.  If using water, always dry the inner surface of the sleeve and outer surface of the penetrants prior to applying the sealant. This is to ensure that the sealant bonds directly to these substrates.  Finally, after applying the MFS sealant over the filler blanket or wrap strip, the best and easiest way to smooth out the sealant is using your hands with soapy water. We would suggest using latex gloves during this process.

Our MPACT® system can be used in A-0 through A-60 steel or aluminum bulkheads or decks.  It is approved for use with a wide range of penetrants such as steel and copper pipes, pre-insulated steel and copper tubes, cables up to 102mm (4 inch) in diameter, cable bundles up to 127mm (5 inch) in diameter and nonmetallic pipes. Intumescent wrap strip is required to be used with nonmetallic pipes.  More information on the MPACT® System and the covered applications, is listed within our Technical Data Sheet and Type Approvals. We are constantly expanding and improving the coverage of our systems, so we encourage you to check in often to find the latest and greatest.

We would greatly appreciate your feedback. Feel free to contact us at techserv@stimarine.com with any questions or comments.