Shore Based Shock Testing Facility
Parent Body: Defence Evaluation and Research Agency (DERA), South Arm Site, Rosyth Royal Dockyard, Dunfermline, Fife, KY11 2XR

Principal Function
Simulation of non-contact underwater explosions using shock machines.

General Details
Three shock simulation machines are available covering a mass range up to 2000kg.  Depending upon the item mass, acceleration levels of 500g can be attained.

Lightweight Shock Machine
The Lightweight shock machine uses a falling weight and a swinging pendulum to provide the loading in each of the three axes to the item under test. Items up to 250 kg inclusive of all fixings can be secured to the shock test plate.

The Deck Shock Machine
The Deck Shock Machine simulates the shock experienced by equipment on ships decks and bulkheads removed from the ships bottom. The nature of the pulse is that of a damped sinusoidal wave with a frequency, depending on equipment mass, of between 23Hz and 27Hz. The machine is capable of applying both vertical and horizontal shock motion to the test item, although not necessarily simultaneously. Rotation of the equipment provides the other horizontal axis.  This obviates the difficulties associated with re-orientating the test item for horizontal tests on machines capable of vertical shock only.

Two Tonne Shock Machine
The Two Tonne Shock Machine provides the capability of testing items of equipment up to two tonnes which are located in the lower hull and bulkhead environments of surface ships and can simulate partial shock levels experienced in submarines. Vertical motion only can be simulated, but depending upon size and geometry, the equipment can be installed into open frame cube to provide athwartship and lateral excitation.

Machine Calibration
The machines are calibrated in accordance with NATO STANAG 4141.

Test Specifications
Shock machines can satisfy current UK shock requirements (BR3021, BR8470, NES 1004, NES 814).

Special Features

• Standard power supplies ranging from 115v to 440 volts 50 Hz are available. Portable generators can provide alternative supplies.

• Water supplies, LP air, photographic support, high speed video.

• Engineering design and fabrication of test rigs.

• Extensive quality instrumentation including strain, velocity, acceleration, displacement captured on high-speed digital data acquisition equipment.

• Software analysis capability, analysis of data in time and frequency domain, export of data in digital format.

• Extensive Modal Analysis facilities and Finite Element Analysis can be provided.

Future Plans
A Lansmont Drop Machine will be commissioned to provide additional facilities for the simulation of half sine and trapezoidal waveforms.

Availability
The facility is available to organisations in the public and private sectors.  Two weeks advanced notice is required to use the facility.

Charging Basis
Cost estimates are provided together with a Scope of Work for Customer review. Enabling Contracts can be created.

Contact Information
Mr Lindsay Morris
Centre for Marine Technology
Marine Structures Department
DERA Rosyth, South Arm Site
Rosyth Royal Dockyard
Dunfermline
Fife, KY11 2XR
Tel: 01383 435190  
Email:  lmorris@mail.dera.gov.uk