Product Data Sheet Show all documents
Sikadur®-31 DW

Sikadur®-31 DW

2-Part epoxy structural adhesive with drinking water contact approval

Sikadur®-31 DW is a 2-part epoxy based moisture tolerant, thixotropic, structural adhesive which bonds most construction materials. It has high mechanical strengths and can also be used for minor concrete repairs, joint filling and crack sealing. Temperature range +10 °C to +30 °C. Internal and external use. It has been specially formulated to meet the requirements for use in contact with drinking water.

  • Can be used in drinking water areas
  • Easy to mix and apply
  • Very good adhesion to most construction materials
  • High mechanical strengths
  • Thixotropic: non-sag in vertical and overhead applications
  • Hardens without shrinkage
  • Different coloured components (for mixing control)
  • No primer needed
  • High initial and ultimate mechanical strength
  • Good abrasion resistance
  • Impermeable to most liquids and water vapour
  • Good chemical resistance
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Product Data Sheet Show all documents

Usage

Structural adhesive for bonding:
  • Concrete elements
  • Hard natural stone
  • Ceramics, fibre cement
  • Mortar, Bricks, Masonry
  • Steel, Iron, Aluminium
  • Wood
  • Polyester, Epoxy
  • Glass
  • Sikadur®-Combiflex® System for drinking water applications
Repair and adhesive for:
  • Corners and edges
  • Holes and void filling
  • Metal profiles
  • Bonding slip bricks
Joint filling and crack sealing:
  • Joint and crack arris / edge repair
  • Sealing non-structural static cracks
 

Advantages

  • Can be used in drinking water areas
  • Easy to mix and apply
  • Very good adhesion to most construction materials
  • High mechanical strengths
  • Thixotropic: non-sag in vertical and overhead applications
  • Hardens without shrinkage
  • Different coloured components (for mixing control)
  • No primer needed
  • High initial and ultimate mechanical strength
  • Good abrasion resistance
  • Impermeable to most liquids and water vapour
  • Good chemical resistance

Packaging

Parts A+B: 6.6 ltrPre-batched unit
(5.00 ltr A comp: 1.60 ltr B comp)

Colour

Part A

White

Part B

Dark grey

Part A+B mixed

Concrete grey

Product Details

Sustainability / Certifications / Approvals

APPROVALS / CERTIFICATES

  • CE Marking and Declaration of Performance to EN 1504-4 - Structural bonding
  • Adhesive for Waterproofing System ÖNORM B 5014 Test 1, Sikadur®-31 DW, OFI Technologie & Innovation GmbH, Test Report No. 408.394
  • Migration Analysis RD 118/2003, Sikadur®-31 DW, O.T.E.C., Test report No. 0761415488
  • Water Regulations Approval BS6920-1, Sikadur®-31 DW, WRAS, Approval No. 1708503
Product Information

Composition

Epoxy resin and selected fillers

Shelf life

24 months from date of production

Storage conditions

The product must be stored in original, unopened and undamaged sealed packaging in dry conditions at temperatures between +5 °C and +30 °C. Always refer to packaging.

Density

Mixed resin: ~2,00 ±0,1 kg/l

Density value at +20 °C

Product declaration

EN 1504-4: Structural bonding
System information

System structure

Refer to the Sikadur®-Combiflex® System product data sheet for all applications with this system.
Technical Information

Compressive strength

Curing time

Curing temperature 23 °C

14 days

~78 N/mm2

Tensile strength in flexure

Curing time

Curing temperature 23 °C

14 days

~37 N/mm2

Tensile strength

Curing time

Curing temperature 23 °C

14 days

~23 N/mm2

Tensile adhesion strength

Curing timeSubstrateCuring temperature

Adhesion strength

7 days

Concrete dry

+23 °C

≥ 4.5 N/mm2 *

7 days

Concrete moist

+23 °C

≥ 4.5 N/mm2 *

7 daysSteel sandblasted+23 °C~ 9 N/mm2

*100 % concrete failure

Shrinkage

Hardens without shrinkage.

Coefficient of thermal expansion

~2,36 × 10-5 (±0,2 × 10-5) 1/K

(EN 1770)

(linear expansion between +23 °C and +60 °C)

Chemical resistance

Resistant to many chemicals. Contact Sika Technical Services for additional information.

Heat deflection temperature

Curing time

Curing temperature

HDT

7 days+23 °C+50 °C

Application

Application Information

Mixing ratio

Part A : Part B = 3 : 1 by weight or volume

Layer thickness

30 mm max.
For non- structural adhesive or other applications, if layer thickness’s of >30 mm are required, apply in successive 30 mm layers or once the previous layer has hardened. The surface of the freshly applied intermediate layers should be scratched to form a key for subsequent layers. If layer application is to be longer than 2 days, the wet applied adhesive must be blinded to excess with quartz sand immediately after application.

Sag flow

Non-sag up to 10 mm thickness on vertical surfaces(EN 1799)

Product temperature

+10 °C min. / +30 °C max.

Ambient air temperature

+10 °C min. / +30 °C max.

Dew point

Beware of condensation.
Steel substrate temperature during application must be at least +3 °C above dew point.

Substrate temperature

+10 °C min. / +30 °C max.

Substrate moisture content

Cementitious substrates must be dry or matt damp (no standing water).
Brush the adhesive well into the substrate if matt damp.

Pot Life

Temperature

Potlife*

Open time

+23 °C

~105 minutes

—
+30 °C—~45 minutes

*200 g

Potlife begins when parts A+B mixed. It is shorter at high temperatures and longer at low temperatures. The greater the quantity mixed, the shorter the potlife. To obtain longer workability at high temperatures, the mixed adhesive may be divided into smaller quantities. Another method is to chill parts A+B before mixing (not below +5 °C).

Waiting time to overcoating

Sikadur®-31 DW may be overcoated with a Sika® compatible epoxy coating when adhesive has hardened
Application steps

SUBSTRATE QUALITY

Concrete / masonry / mortar / stone

Concrete and mortar must be at least 3–6 weeks old.

Substrate surfaces must be sound, clean, dry or matt damp. Free from standing water, ice, dirt, oil, grease, coatings, laitance, efflorescence, old surface treatments, all loose particles and any other surface contaminants that could affect adhesion of the adhesive.

Steel

Surfaces must be clean, dry, free from oil, grease, coatings, rust, scale, all loose particles and any other surface contaminants that could affect adhesion of the adhesive.

Wood

Substrate surfaces must be sound, clean, dry and free from dirt, oil, grease, coatings, all loose particles and any other surface contaminants that could affect adhesion of the adhesive.

SUBSTRATE PREPARATION

Concrete / masonry / mortar / stone

Substrates must be prepared mechanically using suitable abrasive blast cleaning, needle gunning, light scabbling, bush hammering, grinding or other suitable equipment to achieve an open textured gripping surface profile.

Steel

Surfaces must be prepared mechanically using suitable abrasive blast cleaning, grinding, rotating wire brush or other suitable equipment to achieve a bright metal finish with a surface profile to satisfy the necessary tensile adhesion strength requirement. Avoid dew point conditions before and during application.

Wood

Surfaces must be prepared by planing, sanding or other suitable equipment.

All substrates

All dust and loose material must be completely removed from all substrate surfaces before application of the product by vacuum / dust removal equipment.

MIXING

Pre-batched units

Prior to mixing all parts, mix part A (resin) briefly using a mixing spindle attached to a slow speed electric drill (max. 300 rpm). Add part B (hardener) to part A and mix parts A+B continuously for at least 3 minutes until a uniformly coloured smooth consistency mix has been achieved. To ensure thorough mixing pour materials into a clean container and mix again for approximately 1 minute. Over mixing must be avoided to minimise air entrainment. Mix full units only. Mixing time for A+B = 4,0 minutes. Mix only the quantity which can be used within its pot life.

 

CLEANING OF EQUIPMENT

Clean all tools and application equipment with Sika® Colma Cleaner immediately after use. Hardened material can only be mechanically removed.

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