Multiquip ST-45HRM CE manual ST-45HRMCE CONCRETE PUMP— OPERATING PROCEDURES, under pressure

ST-45HRM CE CONCRETE PUMP— OPERATING PROCEDURES

D.Carefully knock the end of the hose away from the reducer.

E.Chip the concrete out of the reducer with the pry bar.

F.Remove the reducer. From the discharge end, chip the concrete out of the shuttle tube with the pry-bar. If concrete cannot be loosened from the outlet of the shuttle tube, remove the clean-out plug on the bottom of the hopper to discharge the concrete.

G.The senior operator may then remove the inspection cover plate from the shuttle tube by using a long extension wrench and the 61 cm (24-inch) pry bar.

WARNING

Make sure the accumulator pressure gauge reads ZERO psi. prior to performing any maitinance or inspection.

H.Chip the blockage out with the pry-bar.

I.Flush the shuttle tube with water.

J.Replace and seal the inspection cover plate on the shuttle tube.

K.Before resuming operation of the pump, perform the “Reverse” Pumping Procedure to relieve pressure on the shuttle tubes.

17.If it is necessary to wait 1/2 hour or more for another load of concrete, and to prevent setting of the mix in the system, it is advisable to consider the following factors (A through D) affecting the concrete :

A.How old is the concrete?

B.Is there an accelerator, calcium chloride, red label, etc., in the concrete?

C.Temperature of the day, 27° C (80° F), 32° C (90° F)?

D.Howmuchsystemyouhaveoutandhowstiffwasthemix you were pumping?

NOTE	When disconnecting hoses, use
	EXTREME CAUTION! The hose is
	under pressure!

If, for any reason, the mix should set up in the system, the following procedure (E through H) is suggested:

E.Disconnectthehosefromthepumpandwashthepump out immediately.

F.Reconnect the hose and fill the hopper with water.

G.Reconnect the hose and fill the hopper with water.DO NOT try to push all the concrete out of all of the hose lines at one time.

Forexample:Ifyouhad 61meters(200ft.)ofsystemout, you would disconnect each hose. Clean it out by push- ing water through the first hose off the pump, then continueprogressingthroughallthehoses,untilallthe system is clean.

H.Ifwaitingtimeisexcessive,itwouldbewisetowashout the pump and hoses and startover when the new truck arrives.This can be avoided by being observant to the pump and system, also taking into consideration the above factors (E through H) affecting the mix.

18.Down-Hill Pumping – can be difficult on some jobs. The slurry procedure would be the same as explained on the pages titled Operating Suggestions. It is suggested that a sponge 5 cm x 10 cm x 15 cm (2”x 4”x 6”) be placed in the hose before the start of pumping. Wet the sponge before placing it in the hose.

Thereasonforusingthewetspongeistokeeptheslurryfrom running too far ahead of the concrete and so reducing the possibility of separation. When the pump is stopped, the material can flow slowly down, due to gravity, and cause the hose to collapse.

When pumping is resumed, you can expect blockage at the point of hose collapse.To prevent this from happening, the hosecanbe“kinkedoff”atthedischargeendwhenthepump is stopped to prevent the gravity flow of the material in the hose.

The use of stiffer mixes when pumping down-hill will de- creasegravityflowofthematerialinthehoseandwillassure a smoother operation between the cam roller bearing and cam plate.As with any job, make sure that the hose and the couplings are in good workable shape.

MAYCO ST-45HRM CE PUMP — OPERATION & PARTS MANUAL — REV. #0 (02/23/04) — PAGE 27