Isobrane-FR Industrial Grade Mass Loaded Vinyl

Description

Isobrane-FR® is a high-density, halogen-free, mineral-loaded flexible noise barrier (MLV) engineered as the heavy mass layer for industrial applications such as automotive, power generation, and petroleum industry. Unlike general-purpose limp mass barriers intended for drywall partitions, Isobrane-FR is formulated for the mechanical, thermal and fire demands of oil and gas piping, LNG facilities, compressor stations, rolling stock and automotive body structures, where the barrier is installed beneath aluminium or stainless-steel cladding, or bonded directly to sheet metal using heat-resistant PSA.

The compound is a Barium Sulphate (BaSO₄) and Calcium Carbonate (CaCO₃) loaded polymer system built on halogen-free recycled polymers, at a nominal density of 2000 kg/m³, or approximately 2 kg/m² per mm of thickness. It contains no lead, no bitumen, no halogens and no odour-producing plasticiser oils, and generates no ozone-depleting substances during manufacture. The material is self-extinguishing with no flaming drips, classified UL 94 V-0 (vertical burn) and UL 94 HF-1 (horizontal burn), which suits it to enclosed plant rooms, cabins, engine bays and locomotive interiors where fire load and drip behaviour are governed.

Acoustically, Isobrane-FR works on the limp-mass principle. Its high surface density and very low bending stiffness push the coincidence dip well above the audible band of interest, so the barrier follows field-incidence mass law across the whole octave range instead of collapsing at a critical frequency the way sheet metal, gypsum or rigid composites do. Measured sound reduction index rises from Rw 21 dB at 1 mm to Rw 32 dB at 5 mm, with the 5 mm grade delivering 28.5 dB at 500 Hz and 38.6 dB at 2 kHz. Because the compound is also viscoelastic, bonding it directly to a panel adds damping as well as mass. It raises the panel’s composite loss factor, shifts resonant frequencies and converts flexural vibration energy into low-grade heat, suppressing the drumming and structural re-radiation that dominates jacketed pipe, duct and body-panel noise.

Isobrane-M – MLV for Metal Jacketing

Isobrane-M is an industry- specific version of Isobrane-FR. In a jacketed pipe or duct build-up, Isobrane-M is not a stand-alone treatment, and it is not buried in the middle of the insulation. It is installed directly beneath the metal cladding as an anti-drumming layer, after all porous insulation layers. This is the position used in acoustic lagging systems certified to ISO 15665 (Acoustics: acoustic insulation for pipes, valves and flanges), and it is the position in which Isobrane-M does two jobs at once.

The reason is the cladding itself. In an insulated pipe system the outer metal jacket, not the pipe wall, is the surface that finally radiates into the workplace, and ISO 15665 notes that the cladding may have a higher radiation efficiency than the pipe at low frequencies. Thin-gauge aluminium or stainless steel is a lightly damped, low-loss-factor shell. It rings, oil-cans and drums, re-radiating energy that the mineral wool has already attenuated, and it is excited both airborne from within and structurally through bands and standoffs. Additional wool does not address this behaviour; damping the cladding does.

Bonded or laid tight against the inner face of the jacket, Isobrane-M acts as a free-layer (extensional) damping treatment with added surface mass. The viscoelastic mineral-loaded compound strains in extension as the jacket flexes, dissipating flexural energy as low-grade heat, raising the composite loss factor of the jacket and suppressing the ring-down that would otherwise dominate the installed result. At the same time it doubles or triples the surface mass of the radiating shell, lifting its transmission loss. The porous layer beneath still provides the decoupling and absorption, so the mass-spring-mass action runs from pipe to wool to a damped, mass-loaded jacket, but the mass and damping are deliberately placed at the radiator, where they are most effective.

Typical Certified Constructions

Published ISO 15665 systems build performance by stacking MLV layers under the jacket, not by moving the barrier inward. A representative progression, using mineral wool, 1 lb/ft² (approximately 4.9 kg/m²) MLV and metal jacketing:

Target class	Porous layer	Isobrane-M position and mass	Cladding
Class A (lower duty)	Approx. 38 mm mineral wool	Not always required on small bore	0.4 mm (0.016″) aluminium
Class A / B	Approx. 100 mm mineral wool (2 × 50 mm)	1 layer under jacket. Minimum 5 kg/m²	0.4 mm (0.016″) aluminium
Class B / C	Approx. 100 mm mineral wool (2 × 50 mm)	2 layers under jacket. Minimum 10 kg/m²	0.5 mm (0.020″) stainless steel
Class C / D (most stringent)	Approx. 100 mm mineral wool (2 × 50 mm)	3 layers under jacket. Minimum 20 kg/m² total	0.5 mm (0.020″) stainless steel

ISO 15665 defines minimum insertion loss in octave bands from 125 Hz to 8 kHz across Classes A, B and C, banded by nominal pipe diameter. The standard applies to cylindrical steel pipes up to 1 m diameter and does not cover rectangular ducting, vessels or machinery. Achieved insertion loss is a property of the complete system. Wool thickness and density, jacket gauge and material, MLV mass and layer count, banding, standoff, seam sealing and valve or flange terminations all govern the result, and performance must be verified by test on the specified construction. Refer to the current edition, ISO 15665:2023, which supersedes ISO 15665:2003.

Pre-Laminated Damped Cladding

Because Isobrane-FR is corona-treated to approximately 45 dynes/cm, it can be factory-laminated directly to aluminium or stainless coil, producing a single damped jacketing sheet that is rolled, cut and banded exactly like plain cladding. This removes a separate wrapping operation from the scaffold and guarantees full-area bond, and therefore consistent damping, rather than the variable contact achieved by hand-laying. It performs markedly better on vertical runs, tanks and vessel walls where a loose barrier tends to slump, and it is a direct, non-staining replacement for bitumen-backed damped jacketing. Available as an OEM laminate. Specify substrate, gauge and Isobrane-FR thickness at enquiry.

Critical: Continuous Service Temperature and Insulation Integrity

Isobrane-FR has a continuous service limit of 70 °C and begins thermal decomposition above 120 °C. In a jacketed pipe system, the entire margin between the process temperature and that limit is provided by the insulation, and by nothing else. The barrier has no thermal protection of its own, no redundancy and no self-limiting behaviour. On a line running at 200 °C or 300 °C, the porous layer is the only thing holding the barrier below its decomposition onset. Insulation quality therefore carries a safety consequence in acoustic lagging, beyond its thermal function.

How Failure Develops

Insulation defects are rarely uniform. They are local, and they produce local hotspots at the barrier plane while the surrounding area stays cool. As a hotspot develops, Isobrane-FR will soften and lose form stability, sag or creep away from the cladding, losing both its damping contact and its uniform surface mass. It will then discolour, off-gas and smoke, and eventually char and melt. The practical consequences go beyond loss of acoustic performance:

• The failure is not visible. It develops under the cladding and usually gives no external indication until smoke or odour appears, by which point the barrier in that zone is destroyed.
• Smoke on an operating plant triggers a response. Visible smoke or fumes from lagging on a hot line will prompt investigation, alarm response and possibly a shutdown, whatever the actual fire risk.
• Molten polymer migrates. Decomposed material can run within the annulus and drip from jacket terminations onto surfaces or personnel below.
• Acoustic performance degrades unnoticed. A slumped or degraded barrier stops delivering insertion loss well before anyone observes a problem, and the system falls out of compliance with the class it was designed to meet.

Common Causes of Hotspots

• Gaps, open butt joints or unstaggered joints between insulation sections
• Crushed or over-compressed wool under banding, at supports, or where trades have stood or leaned on the lagging
• Slumping or settlement of the porous layer on vertical runs and risers, leaving a void at the top
• Missing or reduced insulation at pipe shoes, hangers, supports, elbows, tees, valves and flanges, which are the usual thin points
• Moisture ingress from failed weatherproofing or damaged cladding. Wet mineral wool conducts far more heat than dry, and the effect is progressive
• Insulation disturbed by later construction trades or maintenance and not reinstated to specification
• Insulation thickness specified for thermal or personnel-protection duty only, without checking the barrier-plane temperature
• Upset and transient conditions: steam-out, regeneration, start-up, blowdown or process excursions that far exceed normal operating temperature

Required Design Procedure

1. Calculate the temperature at the barrier plane. It is a function of process temperature, insulation thickness, wool conductivity at mean temperature, pipe diameter and ambient conditions.
2. Use the worst-case sustained condition, not the normal operating condition. Steam-out and regeneration cycles are the most common cause of MLV failure in service. A line that normally runs at 60 °C may see 180 °C for several hours during cleaning. If the barrier cannot survive that cycle it will not survive the plant.
3. Design to a margin. We recommend a calculated barrier-plane temperature not exceeding 60 °C under worst-case sustained conditions, leaving approximately 10 degrees margn against the continuous limit to absorb installation tolerance, wool settlement and ambient variation. Treat the 80 °C intermittent figure as a short excursion allowance, not a design condition.
4. Add ambient and solar gain for outdoor installations, particularly on dark or stainless cladding in hot climates, and in enclosed, poorly ventilated plant spaces.
5. Where the margin cannot be demonstrated, increase the insulation thickness. If thickness is constrained by package space, contact Nankarrow before specification. A custom grade, a different barrier position or an alternative construction may be appropriate.

Required Installation Procedure

• Insulate in two or more layers with staggered longitudinal and circumferential joints, so that no joint forms a continuous thermal path to the barrier.
• Butt all sections tightly. Do not leave gaps to be closed later, and do not fill gaps with offcuts of a lower-density material.
• Use the specified wool density and band tension. Do not over-tighten bands. Compression reduces the effective thickness and the acoustic decoupling at the same time.
• Maintain insulation continuity at supports, shoes, hangers, elbows, tees, valves and flanges. These locations fail thermally and acoustically for the same reason.
• Fit support rings or spacers on vertical runs to prevent settlement of the porous layer.
• Complete weatherproofing and vapour sealing before the system is exposed. Moisture ingress will degrade both thermal and acoustic performance progressively.
• Protect installed lagging from following trades, and reinstate to full original specification after any inspection, NDT or maintenance access.

Verification

A thermographic survey after start-up and before final acceptance is strongly recommended on all Isobrane-FR used in jacketing systems in hot service. It is the only practical way to find local hotspots before they consume the barrier, it is inexpensive relative to re-lagging, and it validates the installation rather than the calculation. Repeat the survey after any significant maintenance intervention that has opened the cladding. Where a plant has recurring steam-out or regeneration cycles, survey during or immediately after a cycle rather than during steady-state running.

Isobrane-FR’s temperature rating is a property of the material, not of the installation. Nankarrow can confirm the material limits and supply grades for specific operating conditions from −40 °C to 80 °C. Responsibility for the insulation design, thickness calculation and installation quality that keep the barrier within those limits rests with the system designer and installing contractor. Where there is any doubt about the achievable margin, contact us before the construction is fixed.

Rail, Locomotive and Automotive Applications

In vehicles, Isobrane-FR is used in two mechanically distinct roles, and specifying it correctly means knowing which problem is being solved. Confusing the two is a common cause of treatments that add weight without moving the measured result.

1. Heavy Layer in a Mass-Spring Trim Part (airborne)

Automotive dash insulators, floor systems and tunnel covers are classically built as a mass-spring barrier system, in which the mass element is a layer of high-density impervious material known as the heavy layer, and the spring element, or decoupler, is a layer of elastic material such as foam or uncompressed felt. Isobrane-FR serves as that heavy layer. It is thermoformable, so it can be moulded to the three-dimensional contours of a firewall, floor pan or wheel arch, and its corona-treated surface bonds reliably to PU foam, shoddy felt and PET fibre decouplers without primer. This supports absorber-barrier-absorber (ABA) constructions in which a fibrous layer is added over the barrier for cavity absorption.

Two design cautions apply. First, the decoupler must remain uncompressed. A heavy layer clamped hard against the panel loses the spring and reverts to a simple mass, forfeiting most of the insertion loss the system was designed to deliver. Second, in an ABA build-up the absorber sits on the barrier and contributes absorption rather than mass. The insulation function is still set by the heavy layer’s surface density.

2. Free-Layer Damping Bonded to Sheet Metal (structure-borne)

Bonded directly to a body panel, floor pan, door skin, wheel arch liner or equipment enclosure with heat-resistant PSA, Isobrane-FR functions as an extensional damping treatment with added mass. It raises the panel’s composite loss factor, shifts resonances out of the excitation range and suppresses the boom and ring excited by engine or traction equipment, road and rail inputs and structural vibration. In this role it is a direct alternative to butyl and bitumen-based deadening sheet, with the advantage that it is bitumen-free, halogen-free, lead-free and free of odour-producing plasticiser oils. That is relevant to cabin odour, fogging and interior air quality qualification, where bitumen products are often difficult to sign off.

Mass Budget as a Governing Constraint

At approximately 2 kg/m² per mm, Isobrane-FR is dense by design, and in vehicles that density has to be managed. Full-coverage application is rarely the right answer. Treat the dominant transmission paths, typically the firewall, footwell, tunnel, wheel arches and floor over the bogie or drive unit, with die-cut Isobrane-FR parts, and use lighter fibrous absorbers elsewhere. Where package space is tight, the OEM density range up to 2400 kg/m³ delivers the same surface mass in roughly 17% less thickness, which is often the difference between a part that fits under trim and one that does not.

This constraint is tightening rather than easing in electric vehicles. Removing the combustion engine removes the broadband masking that concealed road, tyre, wind, HVAC and driveline noise, and exposes tonal motor and inverter content. Barrier performance in the mid and upper bands therefore becomes more audible, not less, even as mass budgets shrink against range targets. Targeted high-density barrier combined with tuned absorption generally outperforms uniform thin coverage.

Fire Performance and Rail Qualification

Rail and locomotive manufacture is the largest single market for Isobrane-FR, and the product is supplied into rolling stock programmes on the strength of its standard fire classification. Isobrane-FR is certified UL 94 V-0 (strict vertical burn, no flaming drips, Report 20613JY), UL 94 HF-1 (strict horizontal burn, after-flame time 3 seconds or less, Report 20613JY1) and FMVSS-302 self-extinguishing. This is the qualification against which the material is approved and repeat-ordered by rail customers. V-0 with no flaming drips is the behaviour that carries most weight in a vehicle context, because a barrier that drips burning polymer onto a floor or into an underframe cavity will propagate a fire whatever its own burn rating.

The formulation supports that rating through its base chemistry rather than by additive alone. Isobrane-FR is halogen-free, bitumen-free and lead-free, with no odour-producing plasticiser oils. In a fire this produces substantially less acid gas and dense black smoke than bitumen-backed or halogenated barrier products, and it aligns with the direction rail fire codes have taken, in which halogen-free FR grades have become the default material choice for compliant rail components.

Batch-Level Testing and Traceability

Rail customers routinely conduct their own incoming fire and physical testing on every delivered batch, and Isobrane-FR is manufactured and documented to support that workflow. Supply under an ISO 9001 quality system includes lot numbering and full batch traceability, certificates of analysis and conformity issued per batch, retained production samples held against each lot for re-test or dispute resolution, and formulation lock. Once a grade is approved for a programme, the recipe, filler system and process parameters are held constant, so that batch-to-batch fire and mechanical results stay inside the window the customer originally qualified. Where a customer’s incoming test protocol has specific sample geometry, conditioning or reporting requirements, these can be written into the supply agreement so that certification arrives with the material.

This matters because mineral-loaded compounds are only as consistent as their filler dispersion and process control, and a formulation that is not held constant can drift across lots. Independent batch verification by the customer, supported by retained samples held by the manufacturer, gives both parties a reference point if a result is ever queried.

Other Fire Standards on Request

Where a project specification calls for a route other than UL 94 or FMVSS-302, additional targets can be evaluated as an OEM programme:

• EN 45545-2: applicable to European rolling stock. It is not a single pass or fail rating. Materials are classified by where they are used, covering interior, exterior, furniture, electrotechnical and mechanical product groups, with each group assigned a requirement set from R1 to R26. Three hazard levels, HL1 to HL3, apply according to the vehicle’s operating context, and compliance is assessed across flame spread, heat release rate, smoke density and toxic gas emission. EN 45545 does not certify a product; it qualifies material and component performance, and OEMs use supplier test reports to demonstrate whole-vehicle compliance. The applicable R-set and hazard level are determined by the car builder for the specific location on the specific vehicle, and testing is arranged against the nominated combination.
• NFPA 130 and associated flame-spread and smoke-density methods, commonly specified for North American transit.

Confirm the required test schedule at enquiry stage so that the correct grade is quoted from the outset.

Service Temperature in Vehicle Applications

The 70 °C continuous limit places Isobrane-FR on the cabin side of the firewall, not the engine-bay side. Underhood ambient temperatures routinely exceed the continuous rating, and heat-soak after shutdown is more severe than the running condition. On rail underframe equipment, confirm the local ambient adjacent to traction converters, resistors and braking equipment. The −40 °C intermittent floor suits cold-climate rolling stock. The upper intermittent figure of 80 °C should be treated as an excursion allowance rather than a design condition, and dark interior surfaces in a parked vehicle under solar load can approach it. Where sustained higher temperatures are unavoidable, ask about custom grades rather than accepting a marginal design.

Typical Vehicle Applications

• Automotive: dash insulators and firewall barriers, floor and tunnel systems, carpet backing, wheel arch liners, boot and parcel shelf partitions, door cavity barriers, moulded and die-cut NVH components.
• Commercial vehicle: cab floors and rear walls, engine tunnel covers, sleeper cab partitions.
• Rail and locomotive: floor constructions over corrugated steel decking, cab and saloon wall and ceiling panels, underframe and roof-mounted equipment enclosures, traction converter and HVAC unit housings, gangway and vestibule treatments, locomotive engine compartment bulkheads on the cool side.
• Supply formats for these markets: die-cut and CNC-profiled parts to drawing, thermoformed 3D components, and laminates with PU foam, PET fibre, shoddy felt or decorative fabric facings.

Vehicle interior and exterior noise targets are typically set against ISO 3381 (interior noise of railbound vehicles), ISO 3095 (exterior noise of railbound vehicles) and, in the EU, the TSI Noise requirements. As with jacketing, Isobrane-FR contributes mass and damping to a system. The achieved cabin level depends on the full build-up, sealing and flanking paths, and should be verified by measurement.

Key Features

• Mineral-loaded, halogen-free formulation. Mineral filled polymer at approximately 2000 kg/m³, free from lead, bitumen, halogens and odour-producing oils.
• Limp-mass acoustic behaviour. Low bending stiffness places coincidence above the band of interest, and performance tracks field-incidence mass law from 50 Hz to 5 kHz.
• Combined mass and damping layer. The viscoelastic compound raises composite panel loss factor when bonded to sheet metal, controlling resonance and panel drumming.
• Self-extinguishing with no flaming drips. UL 94 V-0 (Report 20613JY), UL 94 HF-1 (Report 20613JY1) and FMVSS-302.
• Corona-treated surface. Approximately 45 dynes/cm (45 mN/m) surface energy for reliable PSA wet-out, lamination and composite assembly without primers.
• Wide service envelope. −30 °C to 70 °C continuous, −40 °C to 80 °C intermittent (−22 °F to 158 °F and −40 °F to 176 °F).
• Chemical and moisture resistance. Resistant to water, oil, grease, mineral oil, weak alkalis and weak acids, with water absorption below 0.1%.
• Mechanical strength. Approximately 2.2 MPa tensile strength, 98 N/mm tear strength and elongation above 50%, withstanding banding, handling and thermal cycling on plant.
• Thermoformable. Can be formed into moulded parts, elbow and tee covers and 3D-contoured automotive components.
• Laminatable. Supplied plain or faced with fabrics, foams, polyester fibre, foils or adhesive backing.

Product Specifications: Standard Range

Thickness	Surface Mass	Standard Sheet Size	Sheet Weight	Thermal Conductivity (k)	Thermal Resistance (R)	Rw / STC
1 mm	2 kg/m²	1 m × 2 m	4 kg	0.49 W/m·K	0.002 m²K/W	21 / 21
2 mm	4 kg/m²	1 m × 2 m	8 kg	0.49 W/m·K	0.004 m²K/W	24 / 24
3 mm	6 kg/m²	1 m × 2 m	12 kg	0.49 W/m·K	0.006 m²K/W	26 / 26
4 mm	8 kg/m²	1 m × 2 m	16 kg	0.49 W/m·K	0.008 m²K/W	30 / 30
5 mm	10 kg/m²	1 m × 2 m	20 kg	0.49 W/m·K	0.010 m²K/W	32 / 32

Operating temperature range for all grades: −30 °C to 70 °C continuous, −40 °C to 80 °C intermittent. In hot service the insulation layer alone provides the margin to this limit. See the design and installation procedure above. Thermal resistance is calculated as t/k and is negligible. Isobrane-FR is an acoustic layer, not a thermal insulant, and thermal design must be carried by the mineral wool or blanket in the build-up.

Material Properties

Material type	Heavy mass flexible barrier (mineral-loaded MLV), halogen-free recycled polymer base
Filler system	Barium Sulphate (BaSO4) and Calcium Carbonate (CaCO3)
Density	Approx. 2000 kg/m³
Surface mass	Approx. 2 kg/m² per mm thickness
Shore hardness	Approx. 88A
Tensile strength	Approx. 2.2 MPa
Elongation at break	Greater than 50%
Tear strength	Approx. 98 N/mm
Surface energy	Approx. 45 dynes/cm (45 mN/m), corona-treated
Water absorption	Less than 0.1%
Thermal conductivity	0.49 W/m·K
Thermal decomposition onset	Above 140 °C
Chemical resistance	Water, oil, grease, mineral oil, weak alkalis, weak acids
Colour and texture	Black, smooth. Leather and geometric embossing available
Environmental compliance	Lead-free. RoHS-compliant and LEED-contributing grades available. No ozone-depleting substances in manufacture

Fire Properties

Test Method	Index	Report No.	Description	Result
UL 94	No flaming drips	20613JY	Strict vertical burn test. Complies	V-0
UL 94	After-flame time 3 s or less	20613JY1	Strict horizontal burn test. Complies	HF-1
FMVSS-302	Burn rate 102 mm/min or less	Available on request	Horizontal burn test for motor vehicle interior materials. Complies	Self-extinguishing
Operating temperature range				−30 °C to 70 °C continuous; −40 °C to 80 °C intermittent

UL 94 HF-2, EN 45545-2 and other fire-rating targets can be evaluated for OEM programmes. Where a project calls for ASTM E84 or EN 13501-1 classification, contact Nankarrow before specification so that the correct grade and test route can be agreed.

Manufacturing Tolerances

Parameter	Specification
Length tolerance	±2%
Width tolerance	±2% mm
Thickness tolerance	±5% mm
Weight tolerance	±0.5 kg/m²
Additional barrier weights	Available depending on MOQ
Supply note	Supplied untrimmed. Some surface coverings may overhang the ordered usable width

Engineering and Installation Notes

• Install against the cladding, not inside the wool. Isobrane-FR is positioned as the outermost layer beneath the metal jacket, in full contact with it, so that it damps the radiating shell as well as adding mass. Burying the barrier mid-insulation forfeits the damping function and typically under-performs the same mass installed under the jacket. Only at the most stringent classes is an additional interlayer used, and then in addition to the under-jacket layers rather than instead of them.
• Maximize contact area. Damping is a strain-dependent mechanism and only works where the barrier is coupled to the metal. Hand-wrapped barrier that bridges, tents or slumps away from the jacket delivers mass but little damping. Bond with heat-resistant PSA, or specify factory-laminated damped cladding, wherever consistent loss factor matters, particularly on vertical runs, tanks and vessels.
• Respect the thermal limit. The under-cladding position is the coolest point in the build-up, which is what makes a 70 °C material viable on hot process lines, but the insulation is the only thing providing that margin. Never place Isobrane-FR in contact with the pipe wall, and follow the design, installation and verification procedure set out above.
• Do not compress the porous layer. Over-tight banding collapses the decoupler and short-circuits the mass-spring-mass action. Use the specified band tension, spacing and standoff.
• Seal every seam. A barrier is only as good as its weakest leak path. Overlap seams by 50 to 100 mm and seal with a compatible acoustic tape or sealant. Unsealed penetrations, valve boxes, supports and jacket terminations typically cost more insertion loss than any thickness change.
• Avoid rigid bridging. Screws, rivets or supports that pass rigidly from pipe to outer jacket create structure-borne flanking that will dominate the result regardless of barrier mass.
• PSA bonding. The corona-treated face at approximately 45 dynes/cm gives reliable wet-out for acrylic and rubber-based heat-resistant PSAs without priming. Corona treatment decays with time and storage conditions, so laminate or bond within the agreed window, and validate peel and shear on the actual substrate at service temperature.
• Free layer against constrained layer. Under a jacket, Isobrane-FR functions as a free-layer damper, with the damping layer on the inside face and unconstrained. Where the highest loss factor per unit mass is required on very thin gauge panels, a constrained-layer construction, in which the barrier is sandwiched between the panel and a thin outer constraining foil, is more efficient. Both configurations are available as laminates.
• Layer count against thickness. One 5 mm Isobrane-FR sheet delivers the same 10 kg/m² as two layers of 1 lb/ft² MLV, with half the seams and half the wrapping labour. Check that the specification calls out surface mass rather than a prescriptive layer count before substituting.
• Handling weight. A 5 mm, 1 m × 2 m sheet weighs 20 kg. Plan for two-person handling, or pre-cut and die-cut parts, on overhead and confined-space work.
• Cutting. Cuts cleanly with a utility knife or die. Die-cut and CNC-profiled parts are available to drawing.

OEM Customisation

Parameter	Standard Specification	Customization Range / OEM Possibility
Material	Heavy mass flexible barrier, MLV	Custom mineral-loaded vinyl or EVA formulations
Thickness	1, 2, 3, 4, 5 mm	1 mm to 12 mm
Surface mass	Approx. 2 kg/m² per mm	1.6 to 2.4 kg/m² per mm
Density	Approx. 2000 kg/m³	1600 to 2400 kg/m³
Roll width	1 m	Up to 1.25 m
Roll length	2 m	Up to 10 m
Colour	Black	Other colours subject to MOQ and formulation feasibility
STC rating	Application and system dependent	STC 20 to 60, system dependent
Rw rating	Application and system dependent	Rw 22 to 64 dB, system dependent
Shore hardness	Approx. 88A	Shore A 68 to 95
Tensile strength	Approx. 2.2 MPa	1 to 3 MPa
Elongation	Greater than 50%	Tunable to flexibility requirement
Tear strength	Approx. 98 N/mm	Tunable by formulation
Surface energy	Approx. 45 dynes/cm	Corona treatment level adjustable for bonding and adhesive compatibility
Water absorption	Less than 0.1%	Enhanced moisture-resistant grades
Temperature range	Approx. −30 °C to 70 °C	Custom grades for −40 °C to 80 °C duty
Fire rating	UL 94 V-0, UL 94 HF-1, FMVSS-302	UL 94 HF-2, EN 45545-2 and other targets evaluated on request
Texture	Smooth	Smooth, leather-grain, geometric embossing
Environmental compliance	Lead-free. RoHS-compliant and LEED-contributing grades	Compliance package customised for target market
Supply format	Rolls or sheets	Rolls, sheets, die-cut parts, laminated composites, adhesive-backed, and factory-laminated to aluminium or stainless coil as damped acoustic cladding
Branding	Nankarrow standard supply	OEM and private-label supply
MOQ	As per agreed specification	Depends on thickness, formulation, colour, lamination and packaging

Applications

• Rail and locomotive: Floor constructions, cab and saloon wall and ceiling panels, underframe and roof-mounted equipment enclosures, traction converter and HVAC housings, gangway treatments, and wheel/rail and traction noise control. Supplied to rolling stock programmes on UL 94 V-0, HF-1 and FMVSS-302 classification with per-batch certification and retained samples.
• Oil, gas and petrochemical: Acoustic pipe wrap and metal jacketing on high-pressure piping, valves, flanges, separators and compressor stations, and LNG process lines and modules.
• Automotive and commercial vehicle: Dash insulators and firewall barriers, floor and tunnel systems, carpet backing, wheel arch liners, door cavity and boot partitions, moulded and thermoformed NVH components, and free-layer panel damping as a bitumen-free alternative to butyl deadener.
• Power generation: Turbine hall pipework, ducting, silencer casings and acoustic enclosures.
• HVAC and building services: Duct lagging, plant room enclosures, and plenum chambers between floor slabs, roofs and adjoining partition walls.
• Machinery and industrial: Acoustic enclosures, guarding, panel damping on sheet-metal cabinets, generator and pump housings.
• Composite manufacture: Barrier core in foam/barrier/foam decouplers, fabric- or fibre-faced laminates and die-cut parts.

Trade Information

Principal markets	Railway and locomotive manufacture, oil and gas metal jacketing, automotive and commercial vehicle NVH
Export and supply markets	India, China, Brazil, France, Germany, Italy, Netherlands, Oman, Portugal, Saudi Arabia, South Africa, Thailand, United Arab Emirates, United Kingdom, United States
Monthly supply capacity	300,000 SqM
White label branding	Yes
OEM custom manufacturing to client specification	Yes
MOQ for export	500 SqM
Port of lading	Nhava Sheva JNPT Mumbai (India), Jebel Ali (UAE), Tanjung Priok (Indonesia)
Quality and environment systems	ISO 9001 Quality System, ISO 14001 Environmental System
Batch documentation	Lot numbering and full traceability, certificate of analysis and conformity per batch, retained production samples held against each lot
Formulation control	Recipe, filler system and process parameters locked once a grade is approved for a programme
Customer incoming testing	Supported. Sample geometry, conditioning and reporting requirements can be written into the supply agreement
Warranty	Up to 5 years
Supply formats	Rolls, sheets, die-cut parts, laminated composites, adhesive-backed, metal-laminated damped cladding

Disclaimer

All data and technical information are based on results achieved under typical application conditions. Recipients should clarify with Nankarrow in due time whether the data and information apply to the intended application area. Nankarrow takes every precaution to ensure accuracy, but cannot guarantee that the data is 100% accurate. Minor deviations in colour, quality and dimensions are unavoidable and in most cases do not influence product performance. Nankarrow expressly disclaims all liability in relation to any results obtained from use of the product or reliance on this information. No warranty of fitness for a particular purpose, merchantability or any other warranty, express or implied, is made. All statements herein should be read in conjunction with the customer’s own specification. Where a deviation from our recommendations is required, please contact us in advance to discuss suitable alternatives. Copyright Nankarrow LLC. All rights reserved.