Duursma & Versluijs has several ultrasonic measuring devices, including the DMS 2.
Unlike with almost all other thickness gauges, a display shows the echoes from the material. This allows one to interpret the echoes. Thanks to this technique, it is possible to measure the exact material thickness of the airframe through layers of paint. So grinding away a good layer of paint is no longer necessary, something that is otherwise necessary when a vessel is epoxy coated and one still wants to know the hull thickness. Yacht owners no longer want to damage paint layers with a grinder only to find that everything else is fine.
Concrete
Concrete hulls are checked for cracking, gravel nests, rusting, concrete rot, etc. In addition, standpipes, freeboard, support of overbuilds and running edges, attachment of mooring eyes and bollards are checked.
Steel riveted
Steel riveted hulls are visually inspected internally and externally at the shipyard and then hammered with a large hammer. The steel hull is then ultrasonically measured (using sound waves to determine the thickness of the material). All rivets are visually checked. All skin penetrations are inspected and the propeller is inspected for damage and propeller shaft clearance is measured. The rudder and steering gear are checked. Cathodic protection is assessed. If desired, a plane report is made showing all repairs and measured thicknesses.
The flat report can be used for acceptance with an insurance company.
Steel welded
Steel welded hulls are visually inspected internally and externally at the shipyard. The hull is ultrasonically measured (using sound waves to determine the thickness of the material). All skin penetrations are inspected. Cathodic protection is assessed. If necessary, coating thicknesses are measured. Most steel-welded houseboats are rectangular pontoons. If it is a sailing houseboat, the propeller is additionally inspected for damage and the propeller shaft clearance is measured. The rudder and steering gear are checked.
Aluminum
Aluminum airframes are visually inspected internally and externally. The hull is ultrasonically measured (using sound waves to determine the thickness of the material). All skin penetrations are inspected, the propeller is inspected for damage and propeller shaft clearance is measured.
The rudder and steering gear are checked. For aluminum hulls, extra attention is paid to cathodic protection.
Wood
Wooden hulls are assessed depending on the construction type and method of construction. The rudder and steering gear are checked. The keel and stem attachment is assessed if possible.
Polyester / composite
Polyester/composite hulls are visually inspected internally and externally. The hull-deck connection is checked. The underwater ship is checked for the presence of osmosis and/or delamination. The propeller is inspected for damage and propeller shaft clearance is measured. The rudder and steering gear are checked.
We have different types of moisture meters, where the moisture content in the laminate/sandwich of polyester/composite ships can be determined.
We are:
- HISWA Qualified Yacht Surveyor®.
- NVEP Qualified Yacht Surveyor® (Dutch Association of Experts Pleasure Craft).
- EMCI Registered Yacht Surveyor® (European Maritime Certification Institute).
- Registered Appraiser VRT® (Association of Registered Appraisers).
Rates
We agree on a fixed amount in advance. So that there are no surprises.
If you have any questions or would like a free quote, please feel free to contact us using the quote contact form.
The HISWA pre- purchase survey are carried out under the HISWA general conditions for survey.
Our work area
We perform appraisals, pre-purchase srurvey and surveys assessments throughout the Netherlands.
Upon request and if possible, we can also perform these for you abroad.