Mr Hardy, can you tell us about the MRP development process?



In today's market, where greater emphasis is placed on reliability and lifetime costs, Cryostar saw the need to develop a pump, which was able to meet our customers' demands.

Development of the MRP pump began around three years ago and underwent extensive testing internally before being introduced into the market. The first pump was installed at a customer site just over two years ago. Cryostar currently has around 100 references of the MRP pump installed in the two years since its introduction.

What are the main features of the pump?

The pump is made up of two main components (the cold end & the crank drive). The main features for each of these components can be highlighted as:

Cold End
• Increased volume of the vacuum allowing for lower NPSHr as well as faster cool down.
• New cylinder design with compensator to enable contraction of welds during cool down.
• Large suction chamber allowing more efficient de-gassing.
• Modified design of suction valve giving lower pressure drops and thus improving flow to the high pressure chamber.
• Increased number of piston segments for improved volumetric efficiency.
• New design of low-pressure seals for increased lifetime.
• Maximum safety in LOX service due to 100 per cent filtration & piston made entirely from monel.


Crank Drive
• With either grease or oil lubricated bearings for long life application.
• Internal oil pump for effective circulation of oil into the bearings.
• Improved cross head guiding device for reduced friction and easier maintenance.
• Improved coupling device.


What are the special elements of the new pump?

At its peak performance (25 l/min, 420 bar) the pump is unique and unrivalled in its field. For the MRP pump, Cryostar has initially set the preventative maintenance intervals at 2000 hours for the cold end and 4000 hours for the crank drive. It is expected that with increased feedback from our customers that this could be increased in the future.

Who are the main MRP customers?

All major gas companies globally are using the MRP pump for cylinder filling applications. The MRP is also used by independent gas producers of all sizes as well as for CNG vehicle filling applications. We also have a special version of the MRP pump, which is adapted for hydrogen service.

What kind of feedback have you received from your customers?

Since its introduction into the market place we have monitored both the performance and reliability of this pump with the customer at all of the installed sites. So far we have received no negative comments and all of the customers operating this pump have expressed their satisfaction. A number of our major customers believe that once again Cryostar have developed a pump which cements its position as the technological leader in its field.