Electricity + Control February 2017

VALVES + ACTUATORS

Reducing Operating Costs By Rethinking Air Consumption

Riaan van Eck, SMC Pneumatics

Answering to the call of reduced consumption to not only help lower operating costs but to alleviate pressure on the country’s power is critical in today’s manufacturing environments.

E nergy efficiency, in the past was… and for the foreseeable fu- ture will remain … a hot topic. With end-users becoming more and more discerning and government and economic policies placing pressure on the business sector, the need for a competitive advantage through lean manufacturing and new thinking becomes crucial. Businesses are now under a proverbial microscope where every output needs to be matched by a sustainable and efficient input. SMC Pneumatics (further referred to as ‘the company’) has long looked for innovative ways to reduce consumption. Amongst its array of energy saving solutions and energy saving assessment tools and software are air saving valves. These valves reduce air consumption by up to 40% by operating the return stroke at a reduced pressure.

of the ASR series as well as a flow valve from the ASQ series. These work in conjunction with a speed controller to assist with minimised installation time, reduced mounting height and a more compact ma- chine design. In using the company’s air saving valves, the following benefits become apparent: • Smooth operation of working and return strokes possible thanks to speed consistency through the prevention of jerky movements of working strokes • Improved response time due to less delay of the return stroke by the use of a quick supply and exhaust valve • Easy piping as the body and one-touch fitting allows for 360 de- gree rotations and the sealant on the male thread is standardised • Pressure can be fixed (at 0,2 MPa) or variable (between 0,1 and 0,3 MPa)

Conventional valve

Air saving valve

Working and return strokes operated at the same pressure

Return stroke operated at a reduced pressure

40

Flow valve

Pressure valve

30

0.9 0.7

20

Working stroke

Working stroke

0.5

Return stroke

Return stroke

10

0.3

Return stroke pressure (MPa) 0 0.1 0.15 0.2 0.25 0.3 Air consumption reduction ratio (%)

Working stroke pressure (MPa)

Conventional valve versus air-saving valve According to Compressed Air Best Practices, as industrial automation produces even more sophisticated technology with the advance of robotics, benefits of weight reduction and power conservation, pneu- matic valve designs have begun to find their role in a larger strategy of environmental technology. The company invests 6% of its annual turnover back into R&D each year. Today, alternatives exist and are being designed and bettered on an ongoing basis. As valves evolve to meet needs along with modifications to most pneumatic compo- nents taking place on a very regular basis, the birth of components such as that of the company’s air saving valves becomes more and more necessary. The company offers a pressure valve in the form

Other applications for these air saving valves would be jerk preven- tion in the vertical operation of a cylinder and quick air charge at the end stroke for press applications.

Why so much air wastage? According to a study conducted recently by the company based on Europe’s consumption, the estimated annual industrial electricity consumption is 400 TWh which is divided into three main energy related categories:

Electricity+Control February ‘17

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