New nozzle anti-collision protection system

The most crucial and expensive technology in any waterjet cutting system are the cutting head nozzles from which the stream of highly-pressurized water, with or without abrasive material, is projected onto the workpiece at supersonic speed. The high length/diameter ratio of these parts, combined with the relatively brittle nature of the hard material used, puts them at risk to severe damage should a collision occur during operation. Now, Water Jet Sweden has introduced a unique, patented system to counter these risks.

Protection zone
Customers opting to have the new WJS collision protection system fitted to their water jet profilers will find that each cutting-head nozzle is now surrounded by a 60mm diameter anti-collision protection zone.

The picture shows the cutting head on a WJS Beveljet machine, incorporating bevel-edge cutting and nozzle anti-collision system.

This latest development from WJS ensures that the operational cycle is immediately brought to a safe halt should there be the slightest danger of a collision between the valuable - but vulnerable - nozzle of the head and any obstruction in its path. The most likely source of such collisions are when stray pieces of material being cut from the base stock fail to fall away cleanly and fold up to form a wedge.

Avoidance of downtime
The narrow nozzle tubes themselves are made from a special hi-spec metal in order to withstand the arduous conditions involved and this makes them prone to cracking if placed under undue side-loads. It follows from this that they are quite expensive to replace. A second important benefit provided by the anti-collision system, quite apart from the cost of replacement nozzle tubes, is the avoidance of even more costly downtime and the ability to leave a profiler running unmanned with complete confidence.

A 'win-win' situation
The use of this system will be particularly beneficial to users of large machines where long profiling cycles are more likely to be involved, allowing periods of unattended operation. Another reason is because, even when an operator is overseeing the process, the actual profiling zone is well out of his/her line of sight for most of the time.

Under such conditions, any incipient collision that might arise would not be known until it is too late to prevent damage. But following the automatic intervention of the anti-collision prevention system, say WJS, it is a simple matter to clear the obstruction and to pick up the program from where it was halted without any damage to either the machine or the work in process, and full running can continue without serious interruption.  Refer to page 43

Picture shows the new anti-collision cutting head protection system. For further information, e-mail: info@waterjetsweden.com

A Moog Aerospace test rig will assist Korean Aerospace Research Institute (KARI) to perform a wide range of structural and fatigue tests for helicopters

Moog's Industrial Group, a division of Moog Inc. (NYSE: MOG.A and MOG.B), has delivered an aerospace test rig to the Korean Aerospace Research Institute (KARI) that will perform a wide range of structural and fatigue tests for helicopters. This system is part of a multi-billion dollar procurement project by the South Korean Ministry of National Defense to develop and build 245 utility helicopters over a 16-year period.

Moog's previous experience with similar test rig installations, knowledge of helicopter test techniques and on-the-ground technical support from its Korean engineering team were key reasons for KARI's selection of Moog for this project. That system, which was installed in just three days in 2008, now runs full-scale structural tests and has potential for 12 independent helicopter tests.

Key deliverables of this highly customized test rig installation include: 1) Six cabinets with 16 control channels each. 2) A 256-channel HBM Data Acquisition System. 3) New software functionality that allows Real-Time Ethernet-based data transfer between the command generator (Real-Time Front End) and the localized control loops. 4) A dedicated Ethernet interface for the transfer of the load cell, position and spectrum data from the Moog Test Controller to the CatMan data acquisition unit and activation of commands (e.g. Take Snapshot) from the Test Controller System to the Cat-Man System

The technically-challenging requirements brief sent to Moog specified the need for a vendor to build the hydraulic system, actuator and data acquisition system to carry out static structural tests and fatigue tests for the helicopter rotor system. The hydraulic system was installed in the Rotary Wing Aircraft Laboratory to supply the flow used in the hydraulic actuator for repetitive loading during the fatigue test.

The KARI test rig needed to create and measure forces to simulate and test real-time durability and life of helicopter components-- especially fatigue tests on the rotor, hub and blades. Furthermore, it needed to integrate seamlessly with KARI's existing data acquisition systems and hydraulic control equipment in their new test labs.

"The KARI project was very specific in its requirements and presented us with a really exciting technical challenge. Our engineering team and our depth of experience in aero test rigs and helicopter testing were crucial to the success of this program and we are delighted with the end-result," said Tom Pierce, Business Development Director for test systems. "The new aero test system gives KARI a multitude of benefits ranging from cost efficient operation, virtually unlimited flexibility and total access to local Moog expertise and ongoing system support."

The KARI Load Control System can perform 12 different tests independently with up to eight-channel control stations or one full-scale test. In both cases, up to 96 channels can be used. The load control system has been set up to communicate seamlessly with two different data acquisition external systems (i.e., HBM and VTI) giving KARI the flexibility they require to handle their wide range of tests.

The system also delivers faster, more efficient analysis and comparison of tests. Because the two systems are connected via Ethernet, KARI can directly cross-check data from the Load Control System and Data Acquisition System through time stamps. This allows all data to be stored and archived on a hard disk for post-test analyses.

Currently, KARI's test program runs eight distinct and independent component tests simultaneously. Moog's test rig also needed to allow for future upgrading in line with KARI's plans to develop new facilities to run more ambitious test plans as the helicopter build program expands.

For further information, view website: www.moog.com/industrial    Refer to page 39