Rotary Unions, Swivel Joints,
Air Breather Filters, Flexible Hoses


Designed and Manufactured in the UK, Supplied Worldwide for over 75 years.

07:06:45 BST




The History of Filton - the 1970's

Wednesday 20th April 2022

This year we are celebrating 80 years in manufacturing. Today's blog looks at how our product line developed further throughout the 1970's.

The picture above is for an event Filton attended in 1975.


The requirements for Rotary Unions continued at a pace during the 1970’s. Swivel Joint sales also increased but at a steadier pace. Mechanical seals were becoming more popular and the applications more varied but the majority of business was for small batch sizes. As in previous decades new applications continued to arise, increasing the companies technical experience.


Sadly though, almost 50 years ago now, in May 1972 William Murray, Filton’s founder died unexpectedly. Such was the respect for him that the church was packed with all employees and several European agents. The company passed to William Murray’s daughters, Eileen & Sheilah.  They continued to run the company with the assistance of a very knowledgeable team behind them for another 40 years.


For many years Filton’s French Distributor had been trying to obtain business from a well-known tyre manufacturer but without success. All enquires required ‘specials’ and led to hours of design work taking place.  Early this decade an new enquiry was received from this tyre manufacturer for a 3 port Rotary Union. Design work was undertaken to ensure the specifications were met and an order was placed. This union turned out to be very successful for Filton as the customer concerned advised all their European factories that Filton had been approved for the supply of Rotary Unions.


Many applications arose for Rotary Unions on bottle and can filling machines. Some of the first Rotary Unions were with a two channel Rotary Union (individually sealed) for use on carbon dioxide to pressurise the liquid (soft drinks, beer, cider etc) in the filling machine bowl and the other for compressed air to operate the filler heads. A further development was the use of CIP (cleaning in place) systems for thorough cleaning of the bowls, filling heads and pipework.  This meant that a further port was required and three port Rotary Unions with a stainless-steel construction became very popular.


Occasionally, four port Rotary Unions were required, these were fabricated from stainless steel and contained four Filton bellow seals. The largest four port unit had a 9” diameter and a length of 30”, fortunately space was not a problem as the Rotary Unions were installed on the upper vertical axis of the filling machines. Over the years Filton has provided Rotary Unions for many soft drinks, beer and cider manufacturers.


The Machine tool industry was then added to Filton’s growing list.  This industry saw Filton create a new product line which contained a Filton mechanical seal instead of the bellows seal and a pre-loaded pair of angular contact ball bearings instead of the ball and roller bearings. A concentric ground spigot was added to the rotary connection which also included an ‘O’ ring seal to eliminate the need for a sealing washer.


Another interesting application also occurred for some grinding machines where the workhead needed a mechanical action for operating a chuck but was powered pneumatically. The final design was for an aluminium cylinder/piston mounted on the back of the work head spindle with a three port Rotary Union inbuilt. Two ports were used for piston advance and return with the third port used for coolant or an air blast for the component ejection and swarf clearance. Similar designs were also used for the hydraulic chuck systems on special purpose machine tools.


For a number of years Filton had been providing standard Rotary Unions for a variety of applications in the steel industry.  One application was for use on a laboratory size steel converter. 


An interesting enquiry came for a Rotary Union to handle a hot caustic fluid for the primary processing of alumina during the manufacture of aluminium.  The unit had to be mounted on top of a tank and the fluid passed through to rotary spray arms within the tank.  The Rotary Union also had to take the weight of the spray arms and provide for the drive shaft for rotating the spray.  This combined unit proved more economic than a conventional system with the Rotary Union shaft.


The mechanical seal business continued to expand and included the manufacture of a range of internally and externally mounted seals for a UK company. The first enquiries for mechanical seals  for the pharmaceutical industry also came in during this era, these were to be used on specialised mixing machines.


Filton’s range of Swivel Joints continued to grow including units capable of 400 bar.  A pair of four port and six port Swivel Joints were designed and provided for a nuclear power station.  These were of very high specification, needing full material, physical and chemical certification. 


An unexpected source of orders for multi-port Swivel Joints came from the motor industry for use with water cooling systems.  At the time the motor industry was putting considerable effort into fully mechanising the car body welding systems.  A series of specially designed bronze Swivel Joints were ordered to be installed on the robot welding equipment for a British car plant.


Another unexpected application was in the North Sea oil industry.  An enquiry led to a seven port Swivel Joint being designed.  A ten port Swivel Joint was also installed on an underground road cutting machine for the coal mining industry.


The decade came to a close without it’s founder but Filton had still managed to grow and expand just as he would have hoped.


Next month – the 1980’s.


If you have any questions or if we can help you with your applications you can contact us either by phone on +44 1926 423191 or emailing us on or