Abstract
SummaryAn experimental non-return valve was fitted in the short milk tube so that flow was permitted only in one direction, away from the teat. Liner movement was minimal because no air admission to the liner above the valve was provided. The extent of liner opening therefore depended on the amount of milk extracted within a pulsation cycle and on any air leakage past the liner mouthpiece. Milking experiments using four cows showed that the mean vacuum level in nominally open liners of valved teatcups during peak milk flow was 8·6 kPa higher than in conventional teatcups. Bench tests showed that the increase in liner vacuum (LV) depended on the nominal plant vacuum level, the pressure difference between initial LV and maximum pulsation chamber vacuum, the liner elasticity and mounting tension. The main source of energy available to raise LV above the nominal plant vacuum is the release of strain energy, stored within the liner during the collapse phase of each pulsation cycle.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
