Hydro-expansive rubber seal for blade caisson spacers

Code: PRS.0141

Components: 1

Appearance: Gasket

RINGSEAL L­19 is a rectangular gasket with a central hole of 19 mm x 2 mm, made with a special hydro-expansive rubber that reacts in contact with water by increasing its initial volume. RINGSEAL L­19, used in combination with a normal metal spacer for moulds made of wood ("blade"), hermetically seals the discontinuities which could easily settle in the concrete due to the presence of the spacers; these discontinuities could in many cases pass from one side of the masonry to the other, and which then might seriously compromise the watertightness of the masonry itself.

General characteristics


Shelf-life: 24 months






Suitable for contact with drinking water


Hydroexpansive product: +200 / +900 %

Available colours

- Blue

Packaging and dimensions

- Small bag 200 unit


The hydro-expansive capacity of RINGSEAL L­19 has been tested in the laboratory with three different types of water: demineralised water, salt water and water with strongly basic Ph (to simulate the conditions in contact with the concrete). The expansion tests showed a change in volume ranging from a minimum of about 200% (three times the initial volume) in the case of salt water to a maximum in excess of 900% in the case of demineralised water.

In the standard version, the seal RINGSEAL L­19 is sized for the usual measures of the blade caisson spacers, normally used in the construction industry: in this case with a width of about 20 mm, in the version straight/flat or "twisted" (designed to minimise the propensity to form deformities during the pouring of the concrete in the formwork).


No. 1 RINGSEAL L19 gasket for each "blade" formwork spacer (average 6 - 8 pieces per square metre for wooden formworks of 2 x 0.5 metres).

Use fields

Subterranean construction of concrete by formwork in wood, where the wall is in direct contact with the ground and where there is the presence of waterproofing layers external to the masonry itself: basements, cellars, underground garages, underground environments and basements, etc.

Use method

Place the hydro-expansive seal RINGSEAL L­19 with the appropriate dilating pliers in central position with respect to the length of the blade caisson spacers (one seal for each spacer). Build the planned formwork using the metal spacer for wooden formworks thus prepared and proceed with the usual operations of casting the concrete.

Application methods

- Apply by hand

- Dilating pliers

Permitted supports

- Concrete

- Metallic spacers for wooden formworks


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