Soilmec SR New Generation: Inside the Evolution

Soilmec SR-75

New Generation

The second generation of Soilmec hydraulic drilling rigs, are characterized by various innovative solutions specially designed to increment performance and reliability.  One of the major implementation is the new mast design: lighter, made with high strength steel and with the same geometry for all models. The new SR rig mast features a sensible reduction of the transversal dimensions; this solution together with the use of high strength material allows the highest performance and a streamlined structure in comparison to the previous counterpart model. The Soilmec engineers have also made some little but really useful devices to consolidate the multi-functionality Soilmec rig distinctive features.

All the masts are built with the mechanical predisposition for both winch and cylinder crowd systems. The housings for the WCS pulleys are located in the cathead and lower mast element and in the mid part of the masts main element are the cylinder bracket slots. This concept design allows an easily conversion between the two crowd system versions.

The old and the new mast section in comparison

The cylinder crowd system is usually fitted for bored pile technology for speed requirements, rather than having a longer stroke when using winch crowd. Due to the new mast structure in which the front compartment is not present, as visible in figure  , the cylinder has to be dismounted for transport configuration.

Bracket slots positioning on mast

This necessary solution brought two relevant advantages because, during transport, the rig without the cylinder is lighter and has a lower overall height. An example is the new SR-65, the transport height decreases by 231 mm and the weight by 1150 kg.

Lower Position: Max depth reachable.

In order to preserve the quick rig up characteristics the cylinder mounting process is completely undertaken by the rig, autonomously, using the main rope and a special tool supplied with the machine.

Upper position: Very large diameter tool use

The tool was developed to guarantee an easy and safe assembly operation, sliding the cylinder on the mast guide up to the chosen bracket slot where the operator can fix with a pin and hydraulically connect with quick couplings. In addition the new mast has two locations where the crowd cylinder can be mounted. The two different configurations, which are easily interchangeable, have relative added benefits. When the cylinder is mounted in the lower position the pull down stroke drives the rotary on the bottom mast element allowing the telescopic Kelly bar to reach the maximum depth.

Upper position: More space under the rotary

The cylinder mounted in the upper position gives two different useful features. Dismounting the mast foot allows larger diameter tools to be used enabling full pull down stroke. In addition the elevated position maximizes the clearance under the rotary giving more space for casing and casing oscillator use.