Filling Factories

A Filling Factory was a munitions factory which specialised in filling various munitions, such as bombs, shells, cartridges, screening smokes, etc. In the UK, in both World Wars, the majority of the employees were women.

In the UK, in World War I, such a factory belonging to the Ministry of Munitions was known as a National Filling Factory.

In the UK, in World War II, such a factory belonging to the Ministry of Supply was known as a Royal Filling Factory (RFF), or a Royal Ordnance Factory (ROF). In terms of organisation, they were part of the Royal Ordnance Factory organisation.

Particularly, in World War II, the filling of screening smokes and other pyrotechnic devices was also carried out by fireworks manufacturers; parts of this article do not apply to these fireworks filling factories.

Raw materials

The Filling Factory's raw materials, such as TNT (trinitrotoluene), RDX, or propellants, such as cordite, were manufactured in National Explosives Factories (World War I) or Explosive ROFs (World War II) and transported, by railway trains, to the Filling Factories for filling into munitions, produced at other plants.

High-explosives, such as TNT, had to be heated to melt them and the liquid was poured hot into heated shell cases. Care had to be taken to ensure that there were no voids in the poured explosive charge as this could lead to the shell detonating in the gun barrel during firing.

Shells and gun cartridges were manufactured in the UK, in World War II, by both the Engineering ROFs and private steel works / forging companies. It is believed that the empty brass cartridge cases for small arms were made at the Small Arms Ammunition Factories.

The Filling Factories produced their own pyrotechnics, such as fuzes and screening smokes; as many of these were sensitive materials. They were then filled or assembled directly into the munitions.

They also would have sewn cotton bags for filling with primer composition or cordite charges.

Filling Groups

Filling factories had a large number of buildings. Buildings were needed on the various Groups for filling of munitions. Explosives magazines were required by each Group to store the incoming explosive materials and to store the outgoing filled shells or gun cartridges, usually packed in ammunition boxes. Storage buildings were also needed on each Group to store the incoming empty shells, or cartridges, and the empty ammunition boxes.

For safety purposes, munitions were segregated into different compatibility Groups. A World War II Filling Factory would generally fill several different Groups of Munitions; and these Groups would be located in different geographical areas within the Danger Area of the Filling Factory.

The World War II Groups were:
* Group 1: Initiators, such as caps and detonators for primers and fuzes.
* Group 2: Fuze pellets, exploder pellets, exploder bags.
* Group 3: Filling of fuzes.
* Group 4: Blending of gunpowders for time fuzes.
* Group 5: Filling of cartridges, such as filling cordite into cloth bags or into brass cartridge cases.
* Group 6: Manufacture of smoke producing compositions.
* Group 7: Small arms filling.
* Group 8: Filling of shells or bombs.
* Group 9: Large magazines, filled ammunition awaiting dispatch.In addition, a Filling Factory would have provision for limited proofing and testing of its munitions; and burning grounds for disposal of waste explosive material.

Outside of this Danger Area, but still within the factory site, would be located:
* administration offices;
* pay offices;
* workshops;
* a medical centre;
* changing rooms;
* contraband storage (for items prohibited in the Danger Areas, eg matches, tobacco, etc);
* search rooms;
* canteens (as many as 40 in some of the large factories).

UK World War I National Filling Factories

It is believed that the Ministry of Munitions owned up to 12 factories.

* Royal Arsenal, Woolwich.
* National Filling Factory No. 1, Leeds, (Barnbow).
* National Filling Factory, Hereford.
* Scottish Filling Factory (National Filling Factory No. 4), NFF Georgetown, Renfrewshire.
* National Filling Factory No. 6, Chilwell.
* National Filling Factory No. 7, Hayes, Middlesex.
* National Filling Factory No. 12, Cardonald.
* National Filling Factory No. 13, White Lund (Morecambe).

WW I References

* Cocroft, Wayne D. (2000). "Dangerous Energy: The archaeology of gunpowder and military explosives manufacture". Swindon: English Heritage. ISBN 1-85074-718-0.

UK World War II Royal Ordnance Factory, Filling Factories

Some of these Filling Factories were temporary "war duration" only factories and they closed after the end of World War II. Other Filling Factories were designed to be permanent and to remain open after the War. However only ROF Glascoed is still open and is now part of BAE Systems.

Twenty World War II Filling Factories were planned, but only 16 were built. The two largest UK Filling Factories were:
* ROF Chorley, (Filling Factory No. 1);
* ROF Bridgend, (Filling Factory No. 2).

The other filling factories were:
* ROF Glascoed, (Filling Factory No. 3).
* ROF Hereford, (Filling Factory No. 4) (This was the re-opened World War I National Filling Factory).
* ROF Swynnerton (Filling Factory No. 5).
* ROF Risley, (Filling Factory No. 6).
* ROF Kirkby, (Filling Factory No. 7).
* ROF Aycliffe, (Filling Factory No. 8).
* ROF Thorpe Arch (Filling Factory No. 9).
* ROF Queniborough, (Filling Factory No. 10).
* ROF Brackla, (Filling Factory No. 11).
* ROF Swindon (Wootton Bassett), (Factory No. 12). *
* ROF Macclesfield, (Factory No. 13). *
* ROF Ruddington, (Filling Factory No. 14).
* ROF Walsall, (Filling Factory No. 15).
* ROF Elstow, (Filling Factory No. 16).
* ROF Featherstone, (Filling Factory No. 17).
* ROF Burghfield, (Filling Factory No. 18) (later part of the Atomic Weapons Establishment (AWE)).
* ROF Tutbury, (Factory No. 19) *
* ROF Northampton, (Factory No. 20) *

(Asterisked factories Nos. 12, 13, 19 and 20 were planned, numbers assigned, but not built.)

WW II References

* Cocroft, Wayne D. (2000). "Dangerous Energy: The archaeology of gunpowder and military explosives manufacture". Swindon: English Heritage. ISBN 1-85074-718-0.
* Hay, Ian. (1949). "R.O.F. The Story of the Royal Ordnance Factories: 1939-48". London: His Majesty's Stationery Office.
* Hornby, William (1958). "Factories and Plant. ()". London: HMSO and Longmans, Green and Co.
* Kohan, C.M. (1952). "Works and Buildings. ()". London: HMSO and Longmans, Green and Co.