252404001 S Valve For Putzmeister Concrete Pump
Whats the diffrence between and S-tube and a Rock Valve?
Having used both valves I feel like there are good & bad to both
types. First let me say that as a mechanic there is no question as
to the winner. The rock is WAY easier to service. If the s-tube
boys would get the hopper out of the way that would help a bunch,
but then that would create other problems. I only have two
complaints about the rock.
1. The valve is housed in a very tight area (this is why they can
seperate the hopper before doing any work on the valve) all of the
internal pressure is contained by the very strong lower casting
that contains the valve. Since 90% of pumping is alowing the cyl's
to load properly anything that makes that more difficult is a
serious issue. Bridging of large or excessive ammounts of coarse
aggregate that hampers loading may be more evident with the rock
due in part to the decreased area available to loading.
2. Much is made of "the concrete wearing on other concrete" inside
the valve. My own personal opinion is that it is more efficient to
have the concrete flow in total (as with an s-tube) than fight its
way thru other pressurized stationary concrete as is the case with
the rock.
That being said, and with the understanding that all of this is
just my opinion I will say that until you are asked to pump some
really raggety-assed crete you probably won't know the difference.
In either case the real winner of the 'pump-off' contest will be
the machine with the best maintence of its hyd system and wear
parts. I love s-tubes, but then I no longer have to maintain
them.......... hanging like a bat ;~)
To add a few points for the Rock valve vs S-tube, you can reduce
wear on the Rock by hard surfacing it once a year or every few
years. Because of its wide feed as stated before, concrete wears on
concrete to reduce wear instead of concrete wearing on the bends
inside of an S-tube. This makes the Rock very attractive and as
Schwing advertises its the only rebuildable valve and you get the
most yards in the industry out of a Rock. Also, the pressure spring
under the cutting ring allows equal pressure against the cutting
point and that the sealing point under concrete pressure is not
pressed apart. Therefore because there are no bends in the Rock and
it is sealed with a pressure spring, wear is reduced on the wear
parts when shifting where in the case of an S-tube, it has bends
and to form a proper seal, it must be pressurized with bolts so
when shifting, it is always pressurized against the wear parts
causing premature wear. Another point for the Rock is because of
the way the Rock sits low in the hopper, the concrete isn't
compressed by the swivel body inside the hopper by the hopper
walls. In my opinion, I think the Rock is wide enough that concrete
on concrete while pumping wouldn't cause any problems vs concrete
against metal. I have never used an S-tube but I can imagine what
they are like to clean out compared to a Rock. Like I say I have
never used an S-tube so I don't know too much about them but this
is just my opinion and what I know about the Rock Valve along with
what Speedy and Bob had to say about it.
| Place of Origin | Changsha, China | Brand | ACHIEVE |
| Warranty | 3 Months | Material | Forged, #45 Steel |
| Product Name | S tube/ S valve for Putzmeister | Quality | OEM Standard |
| Model | S2018VN, 2318VP | Application | Putzmeister Concrete Pump |
| Part number: | 252404001, 404556 | Relative Model | For Putzmeister, Schwing, Sany, Zoomlion,Cifa, KCP, Junjin Concrete
Pump |
