Schwing SP 1800-D, Original Operating Instructions

Page: 178 / 390

3.37-2
004.910.01-EN
The following blockages are likely to occur:
1. BLOCKAGE IN THE PUMPING LINE
In the event of a blockage (blockage) of the
pumping line, the pressure rises in the
hydraulic system of the concrete pump until
the pressure relief valve (PRV) opens. The
concrete pump stops, the drive motor runs
under heavy load and the hydraulic oil flowing
via the PRV causes a loud flow noise.
A rapid pressure rise points to a blockage
directly behind the concrete pump
(reduction?). The pressure rise is slower if a
blockage is located at the end of the concrete
pumping line.
The best way to prevent blockages is by
keeping well cleaned, dense pumping lines
and conveying standardised quality concrete.
See chap. 3.80:
CONCRETE TECHNOLOGY CONDITIONS
- Release the blockage by reverse pumping
the concrete with a concrete pump.
- Then pump again carefully.
- Repeat the process, if necessary, until the
blockage releases.
- If reducing the blockage is not possible this
way, the pumping line must be released and
the concerned component removed.
DANGER
Pumping line under pressure!
Never open a pumping line under pressure
and do not tap it.
If concrete emerges under high pressure,
persons can be seriously injured by pulsating
of the pumping line or also at some distance
by flying stones and debris of the pumping
line.
Never try to loosen a blockage by using
compressed air or pressure rise of the
hydraulics. This presses in the blockage
firmer and causes the pumping line to burst.
Possible damage to the machine.
Relieve the pumping line by reverse pumping
the concrete with the concrete pump.
Never work while directly bent over the line.