STP ShaliProtek HR BT 100
A heavy-duty, cold-applied bituminous coating that seals ductile iron pipes, steel and concrete against corrosion, certified safe for contact with potable water.
What is it?
A single-pack, solvent-borne bituminous paint from STP that dries to a smooth black egg-shell matt film, giving ductile iron, steel and concrete an air-tight anti-corrosive barrier.
Where is it used?
External surfaces of ductile iron water main pipes and fittings, mild steel structures and external concrete faces in water-supply, buried-pipeline and industrial projects.
Why use it?
It is non-toxic, imparts no taste or odour to water and conforms to BS 3416 Type II for potable-water contact, so it protects DI mains without contaminating the supply.
How is it applied?
Brush or spray applied by hand or in a workshop onto a clean, dry, mechanically prepared surface, typically in two coats to build the required film.
About STP ShaliProtek HR BT 100
ShaliProtek HR BT 100 is STP’s heavy-duty bituminous coating built specifically for the external protection of ductile iron pipes and fittings. Straight from the tin it is a smooth, brushable and sprayable liquid that dries within minutes to a black egg-shell matt film. What sets it apart from ordinary bitumen paints is its certification: it conforms to BS 3416:1991 Type II, the British standard for cold-applied bitumen coatings suitable for contact with potable water. The film is non-toxic and imparts no taste or odour to water passing through the main, which is exactly why it is specified on drinking-water pipelines where a generic coal-tar or bitumen product would fail approval.
Beyond DI water mains, the same material earns its place on mild steel structures and external concrete faces wherever a durable, low-cost corrosion barrier is needed. The cured coating resists water, dilute acids and alkalis, and natural salts, and stays flexible enough that it does not crack under normal weathering, expansion or contraction. Because it dries rapidly and goes on with nothing more than a brush or spray gun, it suits both factory coating lines and site touch-up of fittings, welded joints and areas where a pipe’s original shop coat has been damaged during handling and laying.
The technical insight
The protection is barrier-based rather than chemically active. ShaliProtek HR BT 100 is a solvent-borne bitumen system, so once the solvent flashes off it leaves a continuous, air-tight bituminous film bonded to the metal. Corrosion of iron and steel needs oxygen, moisture and an electrolyte at the surface at the same time; the coating physically excludes all three, cutting off the water and dissolved salts that drive the electrochemical rust reaction. Bitumen is naturally hydrophobic and chemically inert to dilute acids, alkalis and sea water, which is why the film holds up in buried and damp environments. Its slight flexibility matters just as much as its impermeability: a brittle barrier would micro-crack as the pipe expands and contracts, opening pathways for moisture, whereas this film moves with the substrate. The BS 3416 Type II compliance is the extra layer of engineering, confirming the formulation is low enough in leachable, taste-forming and toxic constituents to sit in permanent contact with drinking water.
Where it is used
- External anti-corrosive coating of ductile iron water main pipes and fittings
- Protection of DI specials, bends and collars where the shop coat is damaged in transit
- Corrosion protection of mild steel structures, brackets and fabricated supports
- Waterproofing and protective coating of external concrete faces
- Buried pipeline protection in water-supply and sewerage schemes
- Factory or workshop coating lines for pipe and fitting manufacturers
- On-site touch-up and re-coating of previously coated iron and steel
- General industrial anti-corrosive duty on plant and equipment exposed to moisture and salts
Key advantages
- Conforms to BS 3416:1991 Type II, certified for contact with potable water
- Non-toxic film that imparts no taste or odour to the water supply
- Fast surface dry of 15 minutes (plus or minus 5), keeping coating lines moving
- Single-pack, ready to use, applied by ordinary brush or spray gun
- Resistant to water, dilute acids and alkalis, and natural salts
- Stays flexible so it does not crack under weathering, expansion or contraction
- Bonds to ductile iron, mild steel and concrete from one product
- Economical theoretical coverage of 5 to 6 m2 per litre per coat
Limitations & considerations
- Solvent-borne with a low 23 degree C flash point, so it is flammable and needs good ventilation and no ignition sources during use
- Bituminous black finish only; it is a protective coat, not a decorative or colour-matched topcoat
- Performance depends heavily on surface prep; loose rust, oil and grease must be removed or adhesion fails
- Not a structural or high-build epoxy lining for internal potable-water surfaces subject to abrasion or pressure
- Hard dry takes up to 8 hours, so handling and overcoating must wait before the film is fully set
- Best kept and applied in cool, dry conditions; heat and damp substrates compromise the coat
Selection & best practice
Start with the substrate. Remove all loose gravel, dirt, oil, grease and foreign matter, blow the surface down with a jet of dry air, and clean it mechanically or by grinding until it is smooth, sound and dry before any coating goes on. Stir the material thoroughly, ideally with a mechanical drill, so the mix is homogeneous. Apply by brush or spray gun in thin, even passes rather than one thick flood coat, which sags and traps solvent. Respect the drying window: the film is surface dry in around 15 minutes but needs up to 8 hours to hard dry, so let the first coat set before recoating and before the pipe is handled or lowered. Because of the 23 degree C flash point, work only in well-ventilated areas away from flames, sparks and hot work, and keep operatives in gloves, eye protection and suitable clothing. Do not thin or clean skin contact with solvent; wash affected skin with soap and water. Store unused material in a cool, dry, shaded place away from heat.
Specifications
| Standard | BS 3416:1991, Type II (for potable water) |
| Colour / Finish | Black, smooth egg-shell to matt |
| Theoretical Coverage | 5 to 6 m2 per litre per coat |
| Surface Dry (max) | 15 plus or minus 5 minutes |
| Hard Dry (max) | 8 hours |
| Viscosity (B4 cup, 30 deg C) | 120 to 180 sec |
| Specific Gravity | 1.2 plus or minus 0.2 |
| Volatile Content | Max 40% by weight |
| Flash Point | 23 deg C |
| Packing | 20 litre and 200 litre containers |
Industry use cases
Water Supply / DI Pipelines
External coating of ductile iron mains and fittings on municipal and industrial water schemes, where BS 3416 Type II compliance keeps the drinking-water supply uncontaminated.
Steel Fabrication & Structures
Anti-corrosive barrier on mild steel supports, brackets and fabricated members exposed to moisture, salts and weather.
Infrastructure & Buried Services
Protection of buried pipelines and specials in water-supply and sewerage works, cutting off moisture and dissolved salts from the metal.
Concrete Protection
Waterproof, protective coat on external concrete faces that need a durable, chemically resistant barrier.
Pipe Manufacturing & Site Repair
Workshop coating lines and on-site touch-up of damaged shop coats on DI pipe, bends and collars before they are laid.
Frequently asked questions
Is ShaliProtek HR BT 100 safe for drinking-water pipelines?
What surfaces can it be applied to?
What coverage should I plan for?
How long does it take to dry?
How is it applied and how many coats are needed?
What safety precautions does it need?
How we position STP ShaliProtek HR BT 100
ShaliProtek HR BT 100 is STP’s go-to bituminous coating for external DI pipe and steel protection where potable-water compliance matters. Within the STP ShaliProtek anti-corrosive family it sits alongside heavier-duty and specialist grades such as ShaliProtek HR BT 300 (formerly HR BT 260), an asphalt-based cold emulsion aimed at internal furnace casing surfaces rather than water mains, so the two are complementary rather than interchangeable. For pipe joints and buried fittings, pair it with STP’s ShaliProtek cold-applied tapes and primers for wrap-around protection. Where a project instead calls for a decorative or higher-build protective finish on above-ground steel and concrete, look to epoxy and polyurethane protective coatings from Fosroc (the Nitocote range) or Sika, which we also stock; for internal potable-water tank and pipe linings, a solvent-free epoxy is the correct choice rather than a bituminous paint. As authorised STP distributors and applicators across Delhi NCR and Pan-India, Space Arc can advise on the right combination and supply the matched primers and tapes alongside the coating.
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