Designing and developing highly innovative products is not a constant process. There are a lot of iteration steps to be made before the final product is ready for production. The production and testing facilities at ALE enable us to rapidly perform these steps. Quick prototyping and testing shortens the overall time-to-market.
Furthermore, ALE is able to produce small series of filament wound composite products. This is particularly useful for producing specialty products, like aerospace (e.g. satellite) components.
ALE is unique in its pressure vessel testing facilities. We are equipped to perform almost all necessary certification tests according to the composite pressure vessel regulations R67-01 (automotive use), EN14427 (domestic use), and EN12245 (other applications).
For other production and testing facilities, ALE works in close conjunction with the Delft University of Technology.
ALE has over 1000 m2 laboratory and production space adjacent to its office in Delft. The production facility includes machines for production of pressure vessels: fast filament winding machine, rubber processing equipement, assembly line and equipment to perform conformity of production tests. Amongst other products, the revolutionary loW8 tank for automotive use will be produced here. Also, a large area is dedicated to custom assembly and production for small series and prototyping.
Fast Filament winder
Conventional filament winding machines are equipped for the use of impregnated fibers. Because of these ‘wet’ fibers, the rotational speed is limited (high speeds would cause the resin to spatter around). ALE’s patented Dry Filament Winding Method does not have this limitation due to resin, and allows us to wind at much higher speeds. To wind at high speeds, ALE has designed and built a fast filament winder. This machine, in combination with specially developed software, is capable of speeds up to 200 rpm, leaving other filament winding machines far behind.
The fast filament winder is mainly used for the production of pressure vessels. A great advantage over ‘traditional’ composites in pressure vessels is the excellent impact behaviour of dry wound vessels, due to the absence of stiff matrix material: in a dry wound structure, the fiber pack deforms on impact en returns to its original shape due to the internal pressure of the vessels. Extensive testing shows no deterioration in burst and fatigue behaviour due to impact.
More information about ALE’s patented Dry Filament Winding can be found at www.low8.com. This site is dedicated to all of our pressure vessel activities.
ALE is unique in its pressure vessel testing facilities. We are equipped to perform almost all necessary certification tests according to the composite pressure vessel regulations R67-01 (automotive use), EN14427 (domestic use), and EN12245 (other applications). These tests include:
impact tests (high speed and low speed)
The test facility is located at the production site.
In order to test whether a pressure vessel will last a certain lifetime, cyclic pressure tests are preformed. We use a RESATO hydraulic pressure testing machine to simulate pressure variations that will occur during the lifetime of a pressure vessel. This test can be preformed at both ambient and high temperatures.
Burst testing reveals the maximum pressure a vessel can withstand. By observing the way and exact place of failure, the design of the pressure vessel can be optimized, if necessary. Burst tests are preformed using the RESATO hydraulic pressure testing machine.
Leak tests are obviously performed to check a pressure vessel on leaks. This can be done using either a fluid or air. Before starting a cyclic pressure test or a burst test, the vessel is checked on leaks using the RESATO hydraulic pressure testing machine. Hence, a fluid is used for leak testing.
To pressure and leak test pressure vessels before delivery, they are pressurized using air. The advantage of using air is that the pressure vessel remains dry on the inside. ALE specially designed a Pressure and Leak Testing Unit (PLTU) for this purpose.
ALE has the facilities to test pressure vessels on impact in a variety of ways, depending on the regulation the vessel has to comply with. This includes impact tests at 50 km/h, wedge impact tests and spike tests.
One of the biggest problems in using composites pressure vessels is permeation. Steel vessels are completely gastight. Composite vessels however leak a certain amount of gas through the wall. The amount of leakage depends on the gas tightness of the wall and the sort of gas inside. Regulation prescribes the maximum allowed amount of permeation. ALE can perform permeation tests on complete pressure vessels, as well as on material samples. For sample testing we’ve developed a Permeation Test Cell.
Materials testing forms an essential part of a quality control program, testing of bulk materials coming into your yard and the laminates you produce can provide the information required to consistently produce high quality products. Improved customer confidence and efficient troubleshooting can be further benefits of implementing a well-structured quality control system. ALE is one of the few companies in the Netherlands that has experience in testing composite materials and we can help you implement your own quality control system if you don’t already have one.
Some of your clients may require approval by a classification society such as ABS, DNV or Lloyds Register. The society will normally require materials testing to be carried out on a calibrated testing facility. We have experience in dealing with these societies.
Information for your Designer
Structural engineering is becoming increasingly important in optimizing performance, cost and safety of composite leisure craft. To do this the designer requires the material properties of laminates produced in your yard.
ALE will prepare test specimens from test panels or material samples that you provide. Alternatively we can provide advice to those who wish to prepare their own samples.
ALE uses calibrated tensile, compressive or fatigue test facilities that range between 10kN and 1000kN and are computer controlled. We also have access to a wide range of other test facilities if required. All test machines are calibrated to aerospace requirements by Nationaal Lucht-en Ruimtevaartlaboratorium, NLR (National Aerospace Laboratory).
ALE’s material testing program involves tensile tests, three-point and four-point bending tests, impact tests, tests at extreme temperatures and electron microscope images. Furthermore we can analyze failure mode and crack growth of composite materials. Non-destructive testing of e.g. laminates through a C-scan is another possibility. These tests can be executed according to international ASTM or DIN standards. We also offer qualification tests in accordance with ABS, GL and DNV standards for the marine industry. A selection of some of the standard tests we perform are given below.
Type of test Applicable standard
Tensile ASTM D3039
Compression ASTM D695 M
Flexural ASTM D790 M / ASTM C393
Interlaminar shear ASTM D3846
Fibre content ASTM D2584
Void content ASTM D2734
On request, any test can be executed according to customer requirements. For information regarding these, or other tests, contact us directly.
ALE will deliver a comprehensive report that conforms to the applicable test standard with each series of tests. This will typically include a detailed description of the test procedure, graphic and numerical results, calculations of material properties and a discussion of the failure modes with accompanying photographs.