4 Strategies for Sealing Wall Penetrations
As a hygienic processor, you work to ensure your plant environment is kept safe, secure, and clean. One complication with maintaining sanitary standards is piping that penetrates through walls, exposing your facility to dust and dirt, and providing a breeding ground for bacteria and pests. Without the right tools, closing gaps that occur can become a difficult and costly problem.
This article is a general education tool for mechanical and electrical contractors, process designers and engineers, production managers and anyone else who has a stake in ensuring that their processing environment is clean and safe.
Before we discuss strategies, let's first define what a piping penetration is.
What is a Piping Penetration?
A Penetration Consists of Three Components
1. Barrier
A structural barrier of some type through which a hole is cut to allow a penetrant (such as a pipe or tube) to pass through.
Some common examples in the processing environment
- Walls
- Ceilings
- Floors
- Electrical panels and enclosures
- Mechanical control panels
- Jacketed tanks or vessels
2. Penetrant
The object that runs uninterrupted through the hole in the barrier, from one side to the other.
This includes
- Process piping and tubing
- Electrical conduit
- Tube-in-tube floor transitions
- Electrical wire and cable
- Hydraulic hoses
- Refrigeration pipe and tubing
- Structural supports and plastic drains or vents
3. Sealing Device
The element that blocks the open area around the penetrant to seal off one side of the barrier from the other.
Examples include
- Temporary seals like putties, sealants or caulks
- Older, more traditional solutions like metal escutcheon wall plates
- Modular mechanical systems
- Newer technologies such as flexible boots
Why is it Important to Seal Penetrations?
In all processing facilities, employee and product safety are the foremost concerns. And a major component in maintaining a safe processing environment is to control the conditions in and around the processing area.
Any unsealed gaps in walls, floors, and ceilings become pathways that allow airborne particles, moisture, and pests to travel from one area to another where they can contaminate the product and create health hazards for employees.
Sealing all of the penetrations in a process setting is an important step in producing a safe product and maintaining a healthy work environment.
What is the Proper Solution?
Penetration Type Determines Sealing Solution
The demands of each application vary widely, so sealing solutions vary depending on a number of factors.
- Sealing new piping
- Sealing around existing piping
- Sealing around wire, cable, tubing or hose
- Fire, pressure or NEMA rating requirements
- Openings in walls, ceilings, or floors
- Openings in thin sheet metal or plastic
- Seals exposed to cleaning solutions or harsh environments
- Seals located outdoors where they are exposed to sunlight and temperature extremes
- Tube-in-tube floor or wall transitions
With these various applications in mind, there are four primary strategies for sealings, each with their own positives and negatives.
4 Sealing Strategies
1. Putties, Sealants, & Caulks
In process piping environments, these options are more of a temporary quick-fix than they are an actual sealing device. Their ability to conform to any shape in order to fill a void makes them a tempting choice to seal penetration gaps.
However, putties, sealants, and caulks merely cover - they do not provide a legitimate seal around the piping surface.
Their inability to remain pliable over time, their inability to withstand movement and vibration, and the mess associated with their application also make them a poor choice.
Pro: (Temporary) quick-fix with the ability to conform and fill most voids.
Con: Do not remain pliable over time to maintain the sanitary seal.
2. Escutcheon Plates
For many years the traditional solution for covering piping penetrations in walls, floors, and ceilings has been to use stainless steel escutcheon plates, also known as wall plates or beauty plates.
They temporarily cover the gap in the opening and provide a decorative trim to the penetration. They are a common and inexpensive solution for covering gaps, but they have proven to be ineffective for most processing facilities.
Most escutcheon plates are installed by applying caulk or sealant to the back of the plate and pressing it against the barrier. They typically remain in position for a brief period until, over time, the caulk or sealant inevitably dries out and loses its adhesive qualities.
Combined with the movement and vibration of process piping,the plate soon separates from the wall, exposes the gap it was meant to cover, and begins to slide down the piping.
Although escutcheon plates are relatively inexpensive and may be a short-term solution to covering piping penetrations, they do not provide a hygienic, permanent seal between the piping and the wall or ceiling. Their design can’t compensate for piping misalignment, pipe slope, movement or vibration.
Pro: Inexpensive, short-term solution that provides decorative trim to penetration.
Con: Over time plates will separate from the wall and lose their hygienic seal.
3. Modular Mechanical Seals
This seal design incorporates a series of elastomer segments or links that are bolted together to form a ring around the penetrant. The ring slides into the opening and, when tightened, expands to fill the gap.
Modular mechanical seals are often used to provide a rigid, watertight seal around pipe penetrations in concrete foundations and structural openings where a hygienic seal is not required.
Each mechanical seal must be assembled using elastomer links, pressure plates, and bolts. Some designs can offer fire-rated or pressure-rated options, but their non-hygienic design precludes their use in food, dairy, beverage, and pharmaceutical environments without being covered by an external seal designed for sanitary settings.
Once installed, the rigid design holds the piping securely and doesn’t allow movement. This feature is an advantage in some utility, drain, or sewer applications but would create stresses in most process piping installations due to thermal expansion and contraction.
Note: If not allowed to flex slightly, piping is subject to material fatigue and potential failure in joints and connections.
Pro: Provides rigid, watertight seal around penetrations.
Con: Non-hygienic design precludes their use in food, dairy, beverage, and pharmaceutical environments without additional seal.
4. Pipetite Flexible Boots
An effective alternative to escutcheon plates is a type of sealing device that incorporates an elastomer boot to seal around the piping. The flexible boot can be trimmed to size in the field to maintain an air-tight seal around the piping.
Unlike a rigid metal escutcheon plate, a flexible design maintains a secure seal around the piping despite pipe slope, misalignment, or movement. The elastomer boot also dampens piping vibration and absorbs noise.
Installation of flexible boot seals is much easier than escutcheon plates due to a self-sealing base that fastens securely to walls, floors, and ceilings using a pre-drilled stainless steel mounting ring with screws. With this design, there is no need for caulks or sealants, and with a mounted base, the boot will not separate from the wall, floor or ceiling.
Pro: A permanent, flexible, and easy-to-install design maintains secure seal despite slope, misalignment, or movement.
Con: Greater initial expense than other solutions.
Next Steps
As a hygienic processor, you work to ensure your plant environment is kept safe, secure, and clean, and the problem of maintaining high standards with piping thatpenetrates through walls needs an effective solution.
That’s where Pipetite® comes in.
Pipetite is designed to completely seal around pipe and tube as it passes through walls and floors. Unlike metal wall plates or escutcheons, Pipetite is flexible, so it stays in place and maintains a seal despite pipeline vibration and movement.
Pipetite products are constructed of hygienic silicone material in compliance with Food and Drug Administration (FDA) specifications. Silicone rubber is resistant to cracking, weathering, extreme temperatures, and water. Even after testing equivalent to 158 years of outdoor use, Pipetite remains waterproof and shows no sign of degradation. Contributing to Pipetite's durability is a temperature rating of -40° to 500°F. Pipetite retains its flexibility indefinitely, regardless of the conditions.
Central States Industrial (CSI) stocks Pipetite in two different warehouses around the US, allowing customers to be reached on-demand. Pipetite is also stocked in several styles and sizes to fit different applications. For a complete overview, visit store.csidesigns.com.
A Guide to Wall Penetration
This technical guide is a general education tool for mechanical and electrical contractors, process designers and engineers, production managers, and anyone else who has a stake in ensuring that their processing environment is clean and safe.
ABOUT CSI
Central States Industrial Equipment (CSI) is a leader in distribution of hygienic pipe, valves, fittings, pumps, heat exchangers, and MRO supplies for hygienic industrial processors, with four distribution facilities across the U.S. CSI also provides detail design and execution for hygienic process systems in the food, dairy, beverage, pharmaceutical, biotechnology, and personal care industries. Specializing in process piping, system start-ups, and cleaning systems, CSI leverages technology, intellectual property, and industry expertise to deliver solutions to processing problems. More information can be found at www.csidesigns.com.