Engineering & Testing Services Hydraulic Fitting Design and Hydro-Mechanical Testing
Aerofit, Inc. APT Laboratory 1425 South Acacia Avenue Fullerton, CA 92831 Main: 714-521-5060 Fax: 714-535-9862 Our Company Aerofit Products was formed on September 5, 1968 and APT Laboratories was established as a hydro-mechanical testing laboratory in March 1972. In March 2004 Aerofit Products and APT were acquired by the present owners and renamed Aerofit, Inc. Aerofit and APT have grown into one of the largest suppliers of standard and specialty fittings in the world. Our manufacturing and testing facilities now encompass over 67,000 square feet. Aerofit designs, manufactures and tests thousands of parts for application in military aerospace, commercial aerospace, marine and nuclear markets. In addition to proprietary parts, we also produce parts to customer specifications, and industry standards. Our goal is to supply our customers with economical, high quality fluid fitting systems and information through a modern production facility and responsive customer support network. Since it was founded, Aerofit has demonstrated its commitment to quality through continuous improvement in its production and product support processing.
Topic Page Engineering & Testing Services --------------------------------------- 4 & 5 Damped Wave Impulse Testing --------------------------------------- 6 Sine Wave Impulse Testing -------------------------------------------- 7 Flexure Fatigue Testing ----------------------------------------------- 8 & 9 Proof & Burst Hydraulic Pressure Testing ---------------------------- 10 Water Pressure Testing ------------------------------------------------ 11 Pneumatic Pressure Testing ------------------------------------------- 11 Salt Spray Testing ------------------------------------------------------ 12 Stress Corrosion Testing ---------------------------------------------- 12 Mechanical Strength Testing ------------------------------------------ 13 Test Specimen Cross Sectioning & Mounting ----------------------- 13 Microscopic Examination & Documentation ------------------------ 14 Test Program Management ------------------------------------------- 14 Test Reports & Major Customers ------------------------------------- 15 3
Engineering Services Our technical staff consists of: Research, Design and Development Engineers Computer Assisted Design (CAD) Draftspersons Laboratory Test Engineers Laboratory Technicians Our unique technical abilities allow us to create mutually beneficial working relationships with our customers in the areas of: Application Design Product Design Installation Tool Design Gage Design Feasibility Studies Qualification Testing Programs Post-manufacturing Functional Testing Programs For more than 35 years we have actively participated in several professional engineering organizations such as the Society of Automotive Engineers (SAE) G-3 Committee, Aerospace Couplings, Fittings, Hose and Tubing Assemblies and the International Standard Organization (ISO) TC/20 and SC/10 Committees 4
Testing Services APT Laboratory is a fully functional Hydro-Mechanical test facility, providing qualification, verification and performance testing of fittings, tube assemblies and hydraulic components. In addition to standardized hydraulic testing, our staff of experienced engineers and technicians can provide guidance for product design and evaluation, detailed test plans, procedures and formal test reports, all of which can be specifically tailored to your applications. Some of the tests we conduct include: Damped wave impulse test per ARP 603 to 8,000 PSI operating pressure with a peak pressure of 12,000 PSI Sine wave impulse test per AS4265 to 30,000 PSI peak pressure Square wave impulse testing to 12,000 PSI peak pressure Flexure fatigue test per ARP 1185 and ISO 7275 up to 8,000 PSI operating pressure Hydrostatic pressure test (proof and burst) to 40,000 PSI with MIL-PRF-83282 hydraulic fluid. Water pressure test up to 15,000 PSI Pneumatic pressure test with nitrogen up to 8,000 PSI Salt spray aging Stress Corrosion Joint strength (Tensile) testing of tube fitting assemblies Repeated assembly Helium leak detection Both Impulse and Flexure tests can be conducted at temperatures ranging form -100 F to +350 F. 5
Damped Wave Impulse Testing Hydraulic impulse testing is used for qualification and performance evaluation of hydraulic system components. Testing for aerospace fitting, tube and hose applications requires pressure peaks above the square wave pressure trace. For testing of aerospace fittings and tube assemblies, it is required that the pressure cycle have a sharp peak, well above the nominal operating pressure. This peak or waveform is created by the sudden introduction of pressure, that simulates the high-stress cycles encountered on aircraft hydraulic systems. APT has three test units that can be used for Damped Wave Impulse Testing. Each consists of a hydraulic power unit, control panel, Tektronix oscilloscope, shock tube with transducer and custom built manifolds for mounting a wide variety of fittings and tube assemblies to be tested in an temperature controlled environmental chamber. Tests are run in accordance to ARP 603. Hydraulic Test Unit Custom Manifolds Testing Chamber These pictures show two custom built manifolds and one of three temperature controlled environmental chambers where samples can be tested with Damped Wave or Sine Wave Impulse under extreme hot or cold temperatures conditions. 6
Sine Wave Impulse Testing The Sine Wave is another form of hydraulic impulse testing, which differs from the Damped Wave method in several ways. The waveform is created electronically by the use of a wave form generator, which is connected to an electronically controlled hydraulic valve located on the test machine. This produces a waveform that is more consistent and easier to reproduce from one test to another. The Sine Wave makes smooth transitions at the peaks, which enables its use at extremely high pressures, and has the capability of being run at a much higher frequency, thus reducing the test time required. APT has one test unit that can be used for Sine Wave Impulse Testing. This is a variable-wave Impulse machine suitable for qualification testing per AS4401 to 30,000 PSI. Custom built manifolds allow a wide variety of fittings and tube assemblies to be tested in an environmentally controlled chamber. Hydraulic Test Unit This is a fixed frequency Sine Wave waveform as seen on an oscilloscope. The lower waveform represents the input signal from the signal generator and the upper waveform represents feedback of the test signal from the transducer. Sine Wave Waveform Temperature Chamber Another view of a temperature controlled environmental chamber with a liquid nitrogen feeder tank attached. Specific test parameters may require soaking at temperature before, at intervals during or after other mechanical testing. 7
Flexure Fatigue Test Mechanical Flexure Testing is a method of determining and classifying the fatigue strengths of re-connectable or permanent hydraulic tube joints. Strain Gage Wires The test specimen typically consists of a fitting joined to a specified length of straight tubing. The assembly is then fitted with strain gages which are used to determine the amount of deflection required to generate the required load or bending stress. Tubing Test Specimen The fitting being tested is rigidly mounted in the manifold that allows the assembly to be pressurized to the operating pressure. Internal pressure is maintained throughout the duration of the test. Rigid Manifold Boring Head The opposite end of the specimen is deflected by moving the boring head off center until the desired bending stress in the tube assembly is reached. This is determined by the strain gage equipment. Optionally, the sample may be setup by deflection at a specified length. Dial Indicator to Measure Deflection Strain Gage Measuring Equipment 8
Flexure Fatigue Test (Continued) Once the setup is completed the sample is pressurized in a range of 1,800 to 3,500 CPM and the boring head is rotated at a test cycle rate. All parameters are maintained until the specimen fails or meets the number of cycles required by the applicable specification. Rotating End Fixed End with Test Fitting Specimens Can Also Be Tested in Extreme Hot or Cold Temperature Conditions Fittings are Tested in All Shapes and Sizes Heating Unit 9
Proof & Burst Hydraulic Pressure Test APT s pressure test machine is capable of achieving and maintaining 40,000 PSI using MIL-PRF-83282 Hydraulic Fluid. This unit is utilized for qualification testing to commercial and military requirements. Pressure Test Chamber Proof Pressure Test: Most specifications require samples to be pressurized at twice the rated system pressure, without leakage for three minutes. Samples are often proof pressure tested prior to other forms of testing to insure their integrity. Test Specimen in Pressure Chamber Burst Pressure Test: The burst test in SAE-AS18280 and similar specifications require the test samples to withstand burst pressure, without leakage or rupture, for five minutes. For operating pressures of 5,000 PSI and less, the burst pressure is four times the rated operating pressure. For 8,000 PSI systems the burst pressure is three times the operating pressure. Samples are often pressurized to failure to determine ultimate burst pressure and failure mode, as shown. Failure 10
Other Testing Capabilities Water Pressure Test APT Laboratory has the capability of water pressure testing hydro-mechanical components in a variety of configurations to 15,000 PSI. Distilled water is often used to proof pressure test assemblies to avoid expensive cleaning processes after testing. Chamber is 2 feet by 2 feet by 1.5 feet deep. Pressure Gage Pressure Test Chamber Pneumatic Pressure Test The test sample is fitted with the appropriate test adapter and is installed onto a flexible hose. The line is purged of air using Nitrogen gas. The test sample is then submerged in water and pressurized with Nitrogen gas until the specified test pressure is achieved. This pressure is maintained for a specified period of time and is monitored for leakage as indicated by bubbles escaping from the test sample. Gas Booster Pneumatic Pump Test Sample Immersion Chamber Test Sample 11
Other Testing Capabilities Salt Spray Testing Salt Spray testing is performed to the test parameters of ASTM-B-117. Testing is available for exposure times varying from a few hours up to thousands of hours. Salt Spray testing is generally used in conjunction with other tests such as flexure and / or impulse. Specific test parameters may require salt spray exposure before, at intervals during or after other mechanical testing. Stress Corrosion Testing Stress Corrosion Testing is conducted using a constant load deflection test fixture. Typically specimens are loaded to various levels of applied stress using a mechanical fixture and measured using a strain gage. It is common to test several specimens at various stress levels. The effects of corrosion on stressed specimens are introduced using salt spray cabinets. The amount of stress, time exposed to corrosion and the concentration of salt is determined by the test parameters. Salt Spray Chamber Multiple Specimen Mechanical Induced Stress 12
Other Testing Capabilities Mechanical Strength Testing Joint strength testing is conducted in accordance with AS18280 and similar procurement specifications. Axial load testing of test specimens and assemblies in either tension or compression can be performed including fabrication of specialized test fixtures. Tube twisting, torque testing, repeated assembly and disassembly testing. Printer Digital Recorder Load Cell Test Specimen Adapters Test Specimen Cross Sectioning & Mounting A number of different sectioning techniques are available to support failure analysis, weld evaluation, microhardness testing and mechanical testing. Precision sectioning can be performed on small parts or for parts requiring examination of small areas of interest. 13
Other Testing Capabilities Microscopic Examination & Documentation Cross sections can be cut from areas of interest in the sample being evaluated and the physical configuration can be examined at various magnifications. Any findings can be documented using digital photography. Test Program Management In addition to our inhouse capabilities we have close working relationships with several other accredited local laboratories where we can outsource testing. Our expert staff manages and monitors such outsourcing with detailed instructions and on site observations of the tests being run. All data is closely evaluated and reported. Some of the types of tests we have outsourced are: Vibration Fatigue Fire Lightning Strike Thermal Shock 14
The End Product The Report The Product is the test report which outlines the methods used and the results obtained for the products, assemblies, or systems tested. Since its inception in 1972 APT Laboratory has conducted test programs for major aerospace companies such as: Boeing Lockheed Martin Cessna Learjet EADS Gulfstream Raytheon Aircraft Dehavilland Bell Helicopter Northrop Grumman Ship Sys. Northrop Grumman Corp. Airbus Hawker Beechcraft Bombardier Fine Tubes Sandvik Specitubes Adel Wiggins Shur-lok Alcoa Hydraflow GE JPL Goodrich A.G. BAE In addition to standardized hydraulic testing, our staff of experienced engineers and technicians can provide guidance for: Product design and evaluation Detailed test plans Procedures & formal test reports All of the above specifically tailored to your application. 15
Aerofit, Inc. APT Laboratory 1425 South Acacia Avenue Fullerton, California,92831 USA www.aptlab.com