Leading spirits manufacturers turn to BM Engineering for purpose built Namur solenoid valves
When a leading producer of spirits called on BM Engineering Ltd (BME) to assist the expansion plans of one of their distilleries, their specialist valve requirements led to the development of a purpose built 5470 Namur solenoid valve solution courtesy of Bürkert. The bespoke solenoid valve was not only cost-effective but also compact and easy to install.
Distillery’s ¼ turn valves requiring speed restrictors
The distillery in question required ¼ turn valves, such as ball and butterfly variants, to be operated either through AS-i or an intrinsically safe barrier with Namur mount solenoid valves with speed restrictors on the opening and closing of the valves. These exacting specifications were required in order to control the opening and closing speed of the valve to prevent problems such as water hammer.
Attaching a needle valve to the inlet port can help regulate the air flow to the actuator. However, attaching a needle valve to the exhaust port on a single-acting actuator is ineffectual because the springs overcome the air flow and push the actuator closed quickly.
In pursuit of a solution, the spirits manufacturer suggested installing a Norgren Flow Regulator Plate along with a 6519 solenoid valve. The end result of such an approach proved to be expensive and bulky.
The solenoid valve that we normally use, the Bürkert 6519 solenoid, doesn’t have speed restrictor features,” says Scott Miller, from BME. “Our customers told us about what our competitors were offering, which was the Norgren Flow Regulator Plate. So we took matters into our own hands and co-developed a solution with Bürkert, which offers speed resistant functionality at a fraction of the cost.
Bürkert’s 5470 Namur Solenoid Valve
Bürkert’s 5470 Namur consists of a type 6104 pilot rocker solenoid valve and a pneumatic valve. An armature with a tilting bearing, similar to a rocker, tilts within the body of the pilot valve, and switches the valve. The minimal tilting movement of the rocker is non-wearing, and basic lubrication is unnecessary.
The Bürkert 5470 Namur has integrated air flow restrictors for both opening and closing operation of the valve, which – as far as we know – is the only Namur solenoid valve on the market with this feature, continues Miller.
Another special feature is that Bürkert UK pre-wires the IFM cables to the solenoid plug by a heat moulding technique. This gives an IP67 rating and eliminates the possibility of loose wiring, as well as providing a streamlined installation process.
Cost-effective and time saving solution
According to Miller, installing Bürkert’s 5470 Namur, as opposed to the Norgren and 6519 combination, returned impressive cost savings. “You’re looking at around £140 for an intrinsically safe 6519, plus around £30 for the Flow Regulator Plate. So, after you add in the cost of cables etc. that brings your costs up to about £190/unit. On top of the solenoid valve that makes it about one and a half times dearer than the 5470s. On that project alone there were around 150 ¼ turn valves.”
BME and Bürkert went one step further to accommodate the needs of the spirits manufacturer by integrating pre-wired IFM cables into the design. The upshot was greater durability and considerable time savings compared to when BME were required to wire the cables themselves.
The customer wanted AS-i or intrinsically safe, depending on what ATEX zone they were in, says Miller. So the sensor on top of the actuator, which links up to the solenoid valve, is an IFM sensor. We were originally getting the IFM cable from the sensor, stripping that cable and wiring them in to the DIN plug for the valve.
It’s tricky because they are very small plugs and very time consuming to wire. Also, the first lot of valves that we sent up resulted in the wires coming loose after a while. So we coordinated with Bürkert once again to implement the solution of heat moulding the cables in. That makes it much more durable and saves us the time of having to wire it in.
The 5470 NAMUR valve has since been used in multiple projects for distilling and other industries including food and beverage and leather. It has become a core product of Bürkert equipment that BME recommends to their customers.