Bonyan modernizes block plant in Kuwait
The well-known concrete block producer on the Kuwaiti market, MS Bonyan is operating several concrete block plants. Thereof a SP 2000 plant delivered through Schlosser Company of Germany and a fully automatic operated Schlosser SV 30 block plant, refurbished, delivered and commissioned through Contec. The SP 2000 plant originally was installed as an economical block plant designed for midsized block factories and supplied in 2002 to Bonyan.
In order to adjust to the increased requirements of the market it was decided to upgrade the SP 2000 plant to be more versatile.
Vibration system and mold clamping
The SP 2000 was standard equipped by two vibrating tables, each equipped by a countercurrent vibrator 25 KN force. This was sufficient to manufacturer standard pavers, interlocks and blocks. However, through rising market demands the company was aiming to manufacture more heavy concrete products like some curbstones, which required a stronger vibrating force to assure a perfect compaction. In addition, one was aiming to reduce and optimize cycle times for the standard interlocks and blocks production. Therefore, the costumer wanted to install a similar vibrating system to the already known vibrating system of their Schlosser SV 30 block machine SynchroVario plus (SVplus). The challenge was to integrate such a strong and flexible vibrating system of max. 140 KN into the overall not that strong designed block machine SP 2000.
In order to cope with that limitation Contec separated the new vibrating system from the machine frame by installing it on a heavy-duty support construction. That insured no vibration transferred into the machine frame during the compaction process and thus leaving the machine frame practically completely stress free from vibration. As a side effect all excessive vibrations, which an end compacted concrete product cannot absorb will not be transferred into the machine frame anymore, but will be deviated through the heavy-duty support construction into the foundation of the machine.
The separated heavy-duty support construction is casted into the machine foundation with a special self-compacting concrete. The new vibrating system disposes of a one-piece, torsion resistant vibrating table with two special vibrators. Each vibrator is mounted by two centrifugal corpuses, which are positioned motorically into the required degree of adjustment. Thus, the vibration force can be adjusted conveniently from the control panel to the various concrete products. The adjustment is effected in shortest time, just slightly longer than an electronically run vibration system. The required degree of adjustment is controlled by a digital positioning device. An interstaged gear assures the two special vibrators are spinning in opposite direction, thus eliminating all unwanted lateral oscillations. Just the required vertical oscillations are transferred into the compaction process.
The SP 2000 is standard equipped by a mechanical mold clamping. To reduce mold-changing times and to support the new installed vibrating system the mechanical mold clamping was replaced by a pneumatically operated mold-clamping device.
Pallet advance and proportional valve
The pallet advance of the SP 2000 is standard equipped by a so-called FMH valve, which controls via a mechanical curve the accelerating and the decelerating speed of the pallet advance. As long as just a few standard products, such as standard interlocks or blocks are produced this mechanical controlled pallet advance device represents an economical and functional solution. Since the costumer was aiming to manufacture more sensible products, in respect of conveying as well, like 50 mm thick curbstones and various other conveying sensible products on the SP 2000 block machine, the stiff pallet advance control through the FMH valve was not suitable anymore.
Contec equipped the hydraulics of the SP 2000 block machine by a proportional valve with an integrated onboard electronic, which is controlled via Profibus and an electronic control card. In order to determine the different speed positions, a touch less digital sensor was installed. By the 3 components, proportional valve with an integrated onboard electronic, an electronic control card with Profibus as well as a touch less digital sensor, all different required ramps and its diverse speed switching positions as well as its various accelerating and the decelerating speeds can be adjusted conveniently from the control panel now.
Draw sheet device and control
To protect the manufacturing pallets Contec integrated a draw sheet device into the pallet advance device. The particular challenge was to design a robust and stable draw sheet device for the manufacturing pallets with a feet height of 320 mm. In order to draw the draw the sheet device smoothly after the compaction process, a mold relief was arranged. Now, the block machine can be operated optionally with or without draw sheet device.
Contec integrated into the existing Siemens Simatic S5 PLC of the SP 2000 block machine a new operating panel and a remote control via ´Team Viewer´, allowing remote online control, if required. The PLC control was modified to control the new vibrating system; the new pneumatically mold clamping device, the new proportional valve with an integrated onboard electronic and digital positioning sensor as well as the new draw sheet device. This top to bottom upgrading was completed and handed over to the customer by Contec in August 2018.
