hi all first post so first things first HELLO,

i run a small putz line pump in the uk and would like some advice on how long i should leave concrete in my lines when i am waiting for the next load. for ex, we did a job today pumping approx 36 m3 the make up took over 90 mins to arrive, this caused us a problem and blocked my pump. so any advice would be welcome.

thats stupid you have plenty of time to wash back to the truck and dump your hopper, then set up the line. charge extra for the wash and to prime up thats how you make money, thats just cost of the job.

eugene lol be nice.

My rule is when in dought wash out. I would never trust that the next truck will arive in time.

hi im from uk also, i would wait upto an hour then wash out our terms of hire states we must have fresh concrete at least every 30 mins. on a boom job if i can circulate i will wait an hour and half depending on mix sometimes 2 hours.   If in doubt wash it out.

 precision pumped

Welcome to the site! There are a lot of variables. It depends on the temperature and the mix etc.. Just remember you are the operator so you are responsible for the pipe and hose and the pump, so when you think it's time to wash out, then do it....If you're not sure then call your manager tell them the situation and let them make the call. 

It depends on conditions,and mix. I always try to leave a full hopper when the mud runs out. loosen it up and give it a stroke or two every 5 min. Maybe pull the hose back and repump into the hopper. 90 minutes is a long time.

A couple of strokes every few minutes until your hopper runs out then u wash out,plain and simple.

many thanks or all your advice, thats a good idea about concrete every 30 mins chris, many thanks for all you help, if you would like to see my pump working you can see it on you tube "precision pumped concrete"