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PERI Tie Technology

Reliable sealing of tie points for concrete formwork

PERI tie technology
SK and DK product brochure

More than 30 pages of valuable expert knowledge – concise, instructive and practice-oriented.

Waterproofing of tie points

The difficulties

The conventional methods used to waterproof tie points are, in practice, not reliable. During hardening, shrinkage cracks form in the concrete which run through the entire wall thickness along the tie point. Difficulties also arise during striking. Construction sequences require striking to take place just one day after concreting. In the process, the tie rod nut is released by means of several hammer blows. Tie rods and mounting parts can therefore be shaken through the vibrations. Furthermore, the tension force of the tie rod acts in one direction after the release of one formwork half. This results in the formation of hairline cracks around the mounting parts. The customary expansion of the tie rod during concreting, and the inevitable compression when being released, results in cracks being formed between the tie rod and concrete.

Faulty mounting of waterstop centre piece

One very common installation error is working with spacer tubes on the two tie rods on either side of the mounted component. These permeable tubes allow the water to penetrate right into the middle of the wall thus making the expensive waterstop centre piece ineffective.

Shrinkage crack formation endangers the water impermeability with waterstop centre pieces ...

Faulty mounting of fibre concrete spacer tube

The biggest disadvantage is that the tubes can split. One hammer blow too many or slight overtightening of the nuts leads to cracking or splitting of the fibre concrete spacer tubes.

... as well as with concreted tie rods.

The requirements

The two variants from PERI fully meet the requirements. In order to seal the tie points, great care must be taken regardless of the method used.

PERI has developed a new technique for the subsequent sealing of tie points. Thereby, there is a much better chance of achieving dense and tight walls rather than using conventional solutions.

By sealing the tie points, the end result can still be influenced whereas embedded sealing components are no longer accessible. And the experienced operator knows just how many uncertainties are involved in concreting and curing.

The solution

PERI Tie Systems DK and SK are:

  • waterproof
  • gas impermeable
  • fire-resistant F 90
  • soundproof

The safe solution

With PERI Tie Technology DK and SK.

A tightly closed tie point is the most cost-effective!

System comparison PERI DK, SK

DK Sealing Cone System 


  • DK Sealing Cones can be effortlessly unscrewed with the cone spanner.
  • DK Sealing Cones can be re-used many times.
  • All DK Sealing Cones DW 15, 20, 26 have the same outside form, i.e. one concrete cone fi ts all cone openings.
  • Targeted use for dealing with seepage water.
  • Waterproof concrete, soundproof and fi reproof walls for wall thicknesses up to 60 cm.


The system consists of 2 re-usable DK Sealing Cones and one concreted Spacer Tube. The end-to-end tie rod is advantageous when shuttering. The Sealing Ring DW 15 between the cone and formwork compensates for any unevenness, and prevents laitance trickling in.

DK System

  • waterproof
  • gas impermeable
  • fire-resistant
  • soundproof

1) Tube, rough (1x)
2) DK Sealing (2x)
3) DK Concrete Cone (2x)

SK Tie Cone System


  • SK Tie Cones have a long service life. Plastic tubes can be replaced.
  • SK Tie Cones can be simply unscrewed for ease of striking.
  • Used for walls in high security areas with lost tie rods.
  • Can also be used as a stable spacer with tube for wall thicknesses greater than 60 cm. The tie rod is re-usable.


The SK System consists of 2 re-usable SK Tie Cones and 3 tie rods, the middle one of which can be embedded in the concrete (e.g. for vaults and strongrooms, and buildings providing radiation protection). For all other applications, a spacer tube is used to enable the middle tie rod to be recovered. The closing process with the Sealing Ring DW 15, 20, 26 is carried out similar to the handling with the DK Sealing System.

SK System Version 1
Re-usable tie rod

  • waterproof
  • gas impermeable
  • fire-resistant
  • soundproof

1) Re-usable tie rod (1x)
2) SK Anchor Cone (2x)
3) SK Concrete Cone (2x)
4) Tube, rough (1x)
5) SK Tube Sealing (2x)

SK System Version 2
Lost tie rod

  • waterproof
  • gas impermeable
  • fire-resistant
  • soundproof
  • suitable for strongrooms

1) Lost tie rod (1x)
2) SK Anchor Cone (2x)
3) SK Concrete Cone (2x)

Important for Tie Systems DK and SK

The spacer tubes must be exactly the same length so that the formwork can be closed cleanly. Otherwise there is the serious risk that laitance can escape, and chipped cone openings as well as bleeding on the concrete surface could occur.

Note: It is important that the spacer tubes of the SK and DK systems are exactly the same length.

The concrete cones

  • Smooth non-porous surface
  • Grey concrete colour
  • Hardness strength in the centre 100 N/mm²
  • Imperviousness tested on the basis of DIN 1048 Part 5 (corresponds to 50 m head of water)

A granular material with particles of a suitable size for the gap is added to the sealing compound which centres the concrete cone in the pocket, and prevents any settling.

Sealing compound

  • 2-component adhesive
  • Grey concrete colour
  • Processing time of 1 hour at 23 °C
  • Salt water resistant
  • Heat and cold resistant
  • Acid resistant to limited extent

In accordance with the KTW recommendation concerning the levels of polymers in drinking water and the recommendation of the DVGW (German Technical and Scientifi c Association for Gas and Water) suitable for:

  • drinking water tanks
  • containers for foodstuffs


Careful working procedures guarantee tight and clean tie points

Removing the DK Sealing Cone

After striking, the DK Sealing Cone is removed by means of the DK Cone Spanner UNI. The spanner is simply fitted on the cone, then slightly turned and pulled out together with the sealing cone. The cones can be re-used.

A careful working procedure when installing the spacer tubes results in tight and clean tie points.

Removing the SK Tie Cone

The following tools are needed to remove the SK Tie Cones:

Cone Tool
SK Anchor Cone
DW 15
Socket SW 27 – 1/2*
item no. 029650
SK Anchor Cone
DW 20
Socket Wrench SW 36
item no. 031480
SK Anchor Cone
DW 26
Socket SW 46 – 1*
item no. 029630

Depending on the SK Tie Cone used, the Socket SW 27, 36 or 46 is required.

Installing the Concrete Cone

The surface of the cone opening must be dry and free of ice, grease and dust.
The surface temperature of the sealing compound, cone and surrounding concrete must be min. + 5 °C.

Coat the cleaned pocket sparingly with the sealing compound.

Hold the concrete cone with a pair of cone pliers, and coat its tapered surface and end evenly with sealing compound.

Insert the concrete cone into the pocket, and turn slightly several times to ensure that the sealing compound is evenly spread.

Tap the concrete cone flush with the cone gauge.

Scrap the surplus compound off with a filling knife.

A clean and tight tie point with the PERI Tie System.

Besonderheiten in der Anwendung

Waterproof concrete

Waterproof is not the same as impermeable to water

“Impermeable to water” is used to describe materials and components into which water cannot penetrate. With “waterproof” components, more water evaporates from the side facing away than penetrates the side in contact with the water.

This means

With sealing cones which are less than 50 mm in length, there is a risk of water penetrating in the vicinity of the tie point, getting round the cone and passing along the shrinkage crack around the spacer tube. For this reason, the Sealing Cones DW 15/55 DK or SK Tie Cones DW 15 should always be used for waterproof concrete.

Gas-proof concrete

Gas-proof is not the same as gas-tight.

The PERI Tie Systems do not affect the diffusion resistance of concrete walls.

Fire protection

When complying with the measures represented in the drawing, the tie point created with the PERI Tie System DK or SK does not have any negative impact on Fire Resistance Class F 90 according to DIN 4102, Part 4.

A tie point formed in this way corresponds to DIN 4102, Part 4 requirements and thus complies with Fire Resistance Class F 90 specifications. Also possible with DK Concrete Cone UNI 58/52.

If the Concrete Cone DW 15-58/30 is installed in an offset manner, the Repoxal Adhesive 031550 must be used. In that case the tie point does not comply with Fire Resistance Class F 90.


Airborne sound

Regardless of the wall thickness, the use of the DK and SK systems does not have any measurable negative influences on the airborne sound insulation of the walls. This applies to all wall thicknesses, with or without insulating board fitted.

Structure-borne sound

With cavity walls, please note that the spacer tubes are not continuous in the area of the insulation. The recommendations for preventing transmission of airborne sound in cavity walls are the same as for solid walls.

Architectural concrete

For different architectural requirements, other concrete cone variants can be used, e.g. recessed or with shadow joint (the colour of the cones may vary).

DK Concrete Cone DW 15-58/30

DK Concrete Cone Architectural 01 DW 15-58/52

Single-sided shuttering against sheet piling

Version 1

With reusable tie rod.

Version 2

With lost tie rods.

Project examples

  • Käppala Sewage Works 2001, Sweden
  • Izmit Sewage Works, Turkey
  • Sewage works in Villach, Austria
  • Elevated Tanks in Weilheim, Germany
  • Gaggenau Groundwater Reservoir, Germany
  • Seitschen Bridge, Germany
  • Spremberg Housing Development, Germany

Overview of system components 

DK Sealing Cones

DK Sealing Cone

SK Sealing Ring

Tube rough

DK Concrete Cone

DK Cone Pliers

DK Cone Spanner

Sealing Compound

SK Anchor Cones

SK Anchor Cone

SK Sealing Ring

Tube rough

SK Tube Seal

DK Concrete Cone

Tie Rod DW

DK Cone Pliers

12-point Nut

Ratchet Wrench

Sealing Compound

PERI tie technology
SK and DK product brochure

More than 30 pages of valuable expert knowledge – concise, instructive and practice-oriented.


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