JOHN DEERE 2020 PROJECT - Part IV

摘要

The rigid pipes are both swaged ended with barrel nuts, each screwed onto a double male adaptor threaded into the pump casting. This set-up rang alarm bells as soon as the spanner was applied to the pressure pipe, as with very little force the nut, adaptor and pipe moved as one. Any further effort applied would have screwed the pipe off; not what was intended. The union between nut and adaptor can be very tight, so the adaptor turns in the pump instead of the pipe slackening off. Our answer was to use two open-ended spanners (and two people), one holding the adaptor rigid (with a little packing the spanner could be jammed against the casting) and the other turning the nut. This was not a job for the faint hearted; by the time we were successful the torque applied must have been in the hundreds of pounds feet! Before removing the pump from its home the unions and pipe ends were sealed to prevent rust as well as contamination. We could use plastic caps for this job, but substantial plastic bags and cable ties do a good job too.