Performance Test of Fire Pump for Offshore North Sea Installation

The SPP 18HXB pump is installed on a Oil Drilling & Production Platform 120 miles off Aberdeen in the North Sea.  On the platform the unit operates as a Fire Pump, meaning that the when called upon, effective operation of the pump is critical.

The pump was removed from site as part of scheduled maintenance programme, overhauled by the OEM and Pump Group were contracted to carry out a witnessed Performance Test of the unit prior to re-installation offshore.

As the whole unit wasn’t removed from the platform, Pump Group had to source the following to facilitate the testing:

• Headpiece & Discharge Bend
• Mechanical Seal & Housing
• Bearing Assembly
• Bearing Cooling Pipework
• Headshaft with Sleeve & Bearing Housing Lock Nuts

As the site motor was still offshore, a suitable slave motor was selected from PSRG Test stock, in this case being a 1490rpm 250kW flange mounted motor.

Prior to the pump arriving at Pump Group premises, our in-house fabricators made a bespoke adaptor piece to connect the test motor to the sourced headpiece.

On site the pump has several ‘riser pieces’, which are straight lengths of pipe between the discharge bowls and the discharge head, combining to give tens of metres of pipe between where the water is being lifted from and the motor/discharge head.  To ensure that the operations engineers could calculate exactly what discharge pressure would be available on site, they specified that Pump Group connected pressure tappings directly after the final pump bowl – before any rising pipe – see below image.

On arrival at Pump Group premises, the pump was installed in the test cell below ground tank, LASER Aligned using Pruftechnik Optalign Smart RS ^©  equipment, and discharge pipework was fitted including throttling valve & calibrated 10″ flowmeter.

Representatives from the client and the Platform Operator attended our site to witness the testing .

The pump was run up to speed and a full performance curve was taken from closed valve to the max flowrate. Condition monitoring readings were recorded using Pruftechnik VibXpert II Dual Channel system, and the vibration spectra were reviewed by the client’s engineers.

Bearing temperatures were logged throughout the duration of the test using a FLIR T420 Thermal Imaging Camara  connected to data acquisition software on a laptop. The engineers selected several specific “spots” on the pump & motor, and the software then plotted the temperature trends showing the ΔT against time.

Following the successful testing, the results were reviewed with the client and Test Certificates were issued with Vibration Analysis & Thermographic reports.

The installation of this pump type off shore is a very expensive undertaking – with weeks of man hours involved to get the pump shipped offshore, loaded onto the platform, removal of the previous pump & motor, installation of the pump, and then installation & alignment of the riser pipes and the riser shaft pieces.

The advantage of performance testing the unit prior to re-installation means that the operator can ship the unit back to the rig with 100% confidence that the pump is operating in accordance with their performance criteria & will work satisfactorily on re-installation

For more information on how we can utilise our extensive workshop and testing facilities to assist your company with your operational needs, please contact a member of our Test Department on +44 (0)161 864 4678 or via email jamespb@pumpgroup.co.uk.