Recycle Gas Compressor: Foundation Repair, Anchor Bolts Replacement and Regrout

Download Success Case

This report underscores the role of a recycle gas compressor in enhancing the efficiency of industrial processes. A well-maintained and properly functioning compressor can increase the reaction rate and yield, while also reducing waste production. However, a poorly designed, constructed, or deteriorated foundation can impact the performance of a recycle compressor. It can lead to reduced efficiency and increased environmental impact. Therefore, it is essential to prioritise the maintenance and upkeep of the compressor to ensure optimal performance and reduce downtime.

The compressor was a Burton Corblin type 164 ME 250 single cylinder compressor, driven through belts by a 45 kW electric motor at 500 rpm. The machine was installed in 1977.

 

 

 

 

 

Features

Client
Couronnaise de Raffinage
Final user
Shell Petit Couronne Refinery
Project
Foundation Repair, Anchor Bolts Replacement, Redesign of Crosshead Support Base, Regrout
Equipment
Burton Corblin Gas Compressor, 164 ME 250 Single Cylinder
Work period
11–21 July 2005
Location
Petit Couronne, Rouen, France

The Problem and Solution

 

The machine was installed without proper grout, leading to lubricating oil leaking into the concrete and down the separations between the anchor bolts and the concrete fill material used as grout, and between this grout and the foundation itself. This caused damage to the foundation. The concrete under the crankcase has lost its resistance to compression, so the machine has been shimmed with thick steel plates. Since these steel plates were resting on deteriorated concrete, they did not help the situation. The vibrations caused deformation of anchor bolts. And finally one of the crankcase anchor bolts sheared completely, and the unit came to a catastrophic halt. The crankcase and the crosshead casing were both severely cracked. 

The solution involved repairing the foundation, removing damaged grout and concrete, and replacing the crankcase and crosshead support anchor bolts. A soleplate installation was used to allow for possible future replacement of the crankcase. The crosshead support, soleplates, and motor bases were aligned and grouted with ALPHATEC® 800 Epoxy Grout, while Grade 8.8 fully threaded rod was used as replacement anchor bolt material. Additionally, the foundation concrete was protected with epoxy grout as a protective capping.

 

The Procedure

 

The compressor was disconnected from the electric motor and dismantled from the foundation. The damaged grout and concrete were then removed from the foundation using appropriate tools to prevent further damage to the compressor and improve the foundation’s integrity.

The crosshead support was inspected to determine the correct dimensions. There were discrepancies about the exact dimensions of the crosshead support, since the existing damaged support did not match up with the original drawings. Eventually a consensus was reached as to the probable correct dimensions, and the client acknowledged the possibility that the dimensions might not be accurate and that in-situ machining could be necessary upon the return of the repaired unit.

The crosshead support, soleplates, and motor bases were aligned in both vertical and horizontal planes, and grouted in place with ALPHATEC® 800 Epoxy Grout. The replacement anchor bolt material used was Grade 8.8 fully threaded rod, which was fully grouted to a depth of at least 12 diameters. The upper part of each anchor bolt was isolated from the grout to allow for proper stretch length of at least 6 diameters.

The bolts were then tightened to the proper loading, which is defined as 50% of the yield strength. The Grade 8.8 bolt material used had a nominal yield strength of 640 N/mm2, and the recommended fastening load is 320 N/mm2. The size, cross-sectional area, fastening load, and torque to apply for the bolts used were specified. 

Finally, the top surface and a short distance down the sides of the foundation concrete were chipped, and epoxy grout was poured overall as a protective capping to prevent further oil ingress. 

 

Conclusion

 

The repair work carried out by Alphatec Engineering on the foundation of the Burton Corblin type 164 ME 250 single cylinder compressor highlights the importance of proper grouting and maintenance of equipment foundations. The use of ALPHATEC® 800 Epoxy Grout, along with Grade 8.8 fully threaded rod as replacement anchor bolt material, provided excellent support and future protection to the foundation.

At Alphatec Engineering, we strive to ensure optimal support and protection of machinery foundations, minimising the risk of vibration-related damage or failure.