December 15, 2017

Ignition Powder Loader


This machine is used to fill a Charge Sleeve on a Header S/A with an Ignition Charge of powder by volume. Typically the Header S/A comes to the machine directly from the Charge Sleeve Welder. The machine is built around a 12 station cam driven index table. The Tooling at each position on the index table consists of a heat treated and polished funnel and a spring-loaded arm used to hold the Header S/A. At the first station, the Header S/A’s are fed from the plastic tube they were loaded into on the Charge Sleeve Welder with the pins hanging down. The clamp arm on the fixture is opened and the Header S/A is moved in under the funnel and roughly located. The clamp arm is then released to hold the Header S/A in the fixture. At the second station, the clamp is released slightly and precision pin with a small lead in chamfer is moved through the funnel and into the hole in the Charge Sleeve.

This precisely locates the hole in the Charge Sleeve with the hole in the Funnel. The clamp is then released to clamp the part with the pin engaged in the Charge Sleeve. Next, the Header S/A and Funnel Tooling is indexed to the powder load station where a spoon is automatically moved into a protective barricade where a feeder bowl fills it with powder. It is scraped off level while exiting the barricade and the powder load is dumped through the funnel into the waiting Charge Sleeve. The powder bowl barricade is built to withstand an explosion of many times as much powder as is allowed in the bowl and direct the blast up through the roof.  It also contains a system that allows the operator to load velostat containers of bulk powder in a secondary barricade which is then automatically transferred to the powder feeder bowl after the outside door is closed. Once the powder load is complete, the Header and Funnel Tooling moves to the Consolidation station and the final heavy consolidation is done. All of the parts are removed at the unload station into an offline powder height check station. Here a precise differential measurement is taken from the top of the Header to the top of the Ignition charge.  Good parts are then transferred onto a vibratory inline feeder for transport to an output loading machine. Reject parts are unloaded and placed into an appropriate explosive material container. Optionally another approach that loads the Header S/A’s from the top into a collet and then moves a slide mounted funnel in over it is also available.

CONTROLS – The control system for this machine is designed to meet the requirements for the powder being used in the area, typically Group 1, Div 1, E, F & G. The control system uses an Allen Bradley PLC5  running a ladder logic program to control the real-time sequencing of the machine.  Operator interface, data logging and any other interface to high-level devices are provided by a custom Microsoft Visual Basic program running on an Intel-powered PC using Windows NT Workstation 4.0 as the operating system.  The control system provides the following standard features as well as many others:

Machine Status display and messages for any machine fault stops.
Storing, loading and editing operational parameters, by customer part number.
Operational Mode selection.
Production data accumulation by Year, Week, Day, Hour and Lot.
Manual control of each output and status monitoring for each input for every station.

CYCLE RATE – 24 Parts/Minute

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