Pneumatic-impact mole-type devices are irreplaceable for trenchless pipe laying of any type and purpose.
Which jacking machine to choose
The jacking machine should be selected strictly for the work being performed. The main parameter is the diameter of the jacking performed or the type of pipe diameters that we install. To this end, you should think about the maximum pipe diameters we will install, so as not to buy too small a machine, because there will be a problem with making larger jackings, or too large, because it is economically unjustified. A compressor with appropriate air flow and operating pressure of 7 bar should be chosen for each machine. The larger the jacking machine, the greater the demand for air. If there is too little air delivered, then we will not use the mole’s full power or there will not even be an opportunity to work. Below, there is a table which shows which compressors are dedicated to which jacking machine diameters. Accessories for each machine are also dedicated to increase its functionality. The jacking machine can be equipped with, among others, a widener, otherwise known as a calibrator. It allows you to make a jacking diameter much larger than the diameter of the machine itself. The table below illustrates which jacking diameters can be obtained using individual moles. It should be accepted and remembered that the final diameter of the jacking, after passage of the mole, will slightly decrease due to the expansion of the soil, compacted as a result of the passage of the mole and depends on the type of soil and the degree of its compaction. When choosing the most suitable machine, we need to assess what diameters we will most often make. If, for example, culverts with a diameter of 130 mm are most often made, and sporadically (in our opinion, no more than 10% of works performed) larger diameters, the most economically justified choice is MAX K130S together with the appropriate widener. We must remember that making the widened hole involves double passage of the mole. This means that first you should make a jacking with the help of the mole, and then release the machine armed with a reamer along the same track. This extends the time it takes us to do the work, but reduces the costs that we would have to incur when deciding to buy an additional mole.
However, if in the future, there is more and more work related to the implementation of larger jacking diameters, the purchase of a larger machine becomes economically justified. A larger machine will allow for faster (in one operation) jacking with a larger diameter, of which we will have more and more. The smaller, previously purchased K130S, will only be used for smaller jacking. The designation of the Terma machine is also its diameter, i.e. the MAX K130S machine has a diameter of 130 mm. And such hole diameter can be made with this machine, without using additional accessories.
The situation is similar when choosing a machine for direct pulling of PE / PVC pipes. The table below presents typical diameters of PE / PVC pipes and machines dedicated for a given diameter.
The RED colour indicates the pipe diameters that can be installed using only the appropriate pipe pulling sleeve fitted in place of the standard screw.
The GRAY colour indicates the pipe diameters for which we will need not only the pulling sleeve or a special towing screw mounted in place of the standard screw, but also a suitable calibrator. PE / PVC pipes with diameters from 25 to 40 mm can be pulled in manually after the performance of the jacking. For pulling in such diameters, a pipe end is used for manually pulling in the pipes. Moles are universal jacking devices. This means that they can be used to install PE / PVC pipes and hammer steel pipes.
The table below shows the capabilities of individual machines in the scope of hammering steel pipes.
As you can see, the larger the machine, the greater the possibilities. However, remember that larger machines are more difficult to manoeuvre with a heavier machine during work. To make the jacking easier, use a machine sized to fit the size of your installation. It is also worth considering the type of soil and the length of the pipe to be hammered. In one case, the K130S will cope well with hammering a 323 mm diameter and 20 meter long pipe. And elsewhere, when we are dealing with extremely difficult ground conditions, only a larger diameter machine will allow for the efficient implementation of a similar task. A smaller machine will also deal with this installation, but the hammering process will take much longer. Remember, however, that in carrying out any work by jacking, the most important factor is the accuracy of the machine itself (in the case of PE / PVC pulling or independent jacking) and proper preparation associated with aiming and directing the machine or / and the hammered steel pipe.
The table below presents dedicated compressors for jacking machines and a link to download a card with the technical data of machines from our offer.
|jacking machine model||jacking diameter [mm]||air flow [l / min]||compressor model|
|other models||above 190mm||7,00||MDVN 82KH|
For all those who decide to buy a set of jacking machine with a compressor, we offer a 7% discount on the total.