Abstract
Kistler Strain Sensors Monitor Welding of ‘difficult’ Materials
World’s leading manufacturer of resistance welding technology, Sciaky Electric Welding Machines Ltd, is using Kistler piezoelectric strain sensors to meet the demands of the aerospace industry for the precise monitoring of the welding process. The Kistler strain sensors are easier to fit, simpler to replace, more reliable and longer lasting than the load cells previously used.
With experience spread over 80 years and an impressive worldwide customer list, which includes most of the leading automobile and aerospace companies, Slough-based Sciaky has led the way in the development of resistance welding, especially of ‘difficult’ materials. In particular, aerospace applications, where very clean aluminium and titanium are welded, demand reliable monitoring of the welding process. A critical parameter is the force exerted by the welding electrodes, which was previously measured by a load cell installed inside the ram connecting the weld cylinder to the electrode control mechanism. This required special machining and significant dismantling when replacement was needed. By contrast, the Kistler piezoelectric strain sensor, mounted externally on the main structure of the machine, requires only simple machining to provide a flat seating and a single tapped hole for mounting the sensor.
Unlike the load cell, the piezoelectric strain sensor measures the force at the electrodes indirectly by reference to the strain on the main body of the machine. The conversion from strain to force is achieved using a Kistler Type 5073A single-channel industrial charge amplifier which is mounted on the machine remotely from the sensor.
In addition to fitting the sensors to new welding machines, Sciaky now retrofit the Kistler strain sensor whenever the old-style load cell needs replacing. According to Sciaky’s Managing Director, Louis Kunzig, the strain sensor is now fitted as standard to all Sciaky resistance welding machines supplied for aerospace applications and for critical applications, such as manufacturing steering components, in the automobile industry.
Kistler Instruments Limited
01256 741550
Seaward HAL104 Shines in Testing at Lighting Specialists
Martech UK Ltd, which designs and manufactures a wide range of energy-efficient light fittings, has improved its electrical safety testing procedure by installing an automatic system provided by the advanced HAL 104 from Clare.
At its factory in West Yorkshire, Martech has been using 10 HAL 104s on stock, assembly and sub-assembly production lines to test upwards of 600 units which it manufactures daily.
There, the HAL 104s perform a range of classes I, II and III tests to ensure compliance with EN 60598 and guarantee product quality, performance and reliability, including earth continuity, insulation resistance test and light-up/load test.
Function testing is also undertaken as part of a production line programme to check that units switch on/off and light correctly and that any ancillary equipment works in accordance with stringent performance criteria.
The digital HAL 104s, which replaced three different types of test equipment, are fast, high-performance automatic instruments which record test results and ensure accurate testing is carried out in line with relevant product standards at all times.
This ensures that products leaving the factory gate are safe to use and that damage to delicate electronic and electrical components is avoided in line with the company’s quality assurance programme.
The HAL 104 combines the performance of a multi-function production line safety tester with load and power factor measurements for product energy consumption and rating assessments.
The instrument meets the end-of-line electrical safety compliance tests required by the majority of national and international product safety standards, including EN 60335, EN 60745, EN 60598 and others.
In addition to load and power functional tests, the new tester incorporates alternating current/direct current (AC/DC) Hipot (flash/dielectric strength), insulation, ground/earth bond testing to programmable up to 40 A, load switching to 26 A with measurement to 20 mA and leakage to 100 µA.
The new tester has widespread applications in production situations where high-resolution performance measurements are important and can be used as a manual stand-alone tester with simple push button test activation.
Alternatively, it can be fully integrated into automated manufacturing systems with selectable sensors and enclosure interlocks or by ultimate control using remote PCs and programmable logic controllers (PLCs).
A large, clear, full-graphic display presents information either in numerical or in analogue format, and a powerful internal memory allows the storage of up to 6000 test results and up to 50 configurable test routines. The instrument can also be interfaced with a variety of accessories ranging from bar code scanners to pass/fail label printers.
The HAL 104 meets all of the requirements of the various British and European standards in relation to high-voltage testing and incorporates fully isolated high-voltage outputs to ensure the highest levels of operator safety.
Rotork Increases its Valve Instrumentation Product Range
Market’s leading actuator manufacturer and flow control company Rotork plc has expanded its range of instrumentation products with the acquisition of Young Tech Co. Ltd (YTC).
YTC is a Korean-based, ISO9001-certified manufacturer of positioners and accessories mainly associated with pneumatic valve actuation. YTC products, including electro-pneumatic, pneumatic and smart positioners; solenoid valves and I to P converters, are widely recognised in worldwide flow control markets and industries. International hazardous area certifications include Appareils destinés à être utilisés en ATmosphères EXplosibles (ATEX), International Electrotechnical Commission Scheme for Equipment for Use in Explosive Atmospheres (IECEx), Canadian Standards Association (CSA) and Factory Mutual (FM).
The acquisition of YTC, which will become part of the Rotork Instruments Division, is in line with Rotork’s strategy of extending its offering of flow control and pressure control products. The acquisition further enhances Rotork’s position in the Asia-Pacific market, while increasing YTC’s presence in Europe and the Americas.
Rotork – Sarah Kellett
+44 (0) 1225 733200
High-Temperature Connectors Function in Environments up to 200 °C
HARTING has introduced a new high-temperature connector family, the Han(R) HighTemp Series, which enables the reliable transmission of signals and power at temperatures up to 200 °C in industrial environments.
The design of the Han(R) HighTemp Series is based on HARTING’s well-established Han(R) B and Han(R) E series with the addition of high-quality temperature-resistant materials and heat-resistant design applied to all components such as contacts, insulating materials, housing, seals and grounding elements. During development, the resistance of these components was verified in HARTING’s in-house testing laboratory.
The basic structure of the Han(R) HighTemp connector consists of a bulkhead-mounted housing and a cable-side hood. The aluminium die-cast hoods and housings feature a highly compressed surface with excellent non-stick properties. It also has a special non-stick coating on the bulkhead-side seal which allows easy handling without significant sticking.
The rugged contact inserts use liquid crystal polymer (LCP) injection moulding to deliver outstanding temperature resistance coupled with excellent mechanical stability. The temperature-resistant contacts, for either screw or crimp termination, ensure reliable connections with minimal contact resistance even at extreme temperatures.
High-temperature connectors offer significant savings in equipment design, manufacture and maintenance by removing the need to enclose machine parts which are exposed to high temperatures and clearing the way to modular plug-in designs. The resulting lower wiring complexity results in reduced maintenance costs, fewer outages and minimal down times.