In today's world, whenever there is a successful product that comes to market there is often similar machines that will be offered soon thereafter. Hydraulic cutters, also known as rock grinders, rotary cutters, twin headers, drum cutters etc., in their original form have been offered since the 1970s when roadheader (continuous miner style) transmissions were converted to be operated hydraulically and mounted on a variety of carriers including excavators. Since then the variety of designs have evolved and now vary substantially despite looking similar to someone new to the product. It is however the intricate details of the design and manufacturing process that differentiates these hydraulic attachments.
The drums or cutting heads themselves are what is of course contacting the rock or concrete directly therefore playing an essential role in the machines cutting performance and durability. Antraquip offers a variety of customized drums/heads depending on the application but the standard heads are designed to maximize productivity in terms of material cut and of course durability to maximize life of the drums with relatively minimal maintenance. The standard drums are very aggressively laced meaning the attack angle of the cutter bits (picks) is quite steep, therefore removing the maximum amount of material with each revolution. With such an aggressive lacing pattern, it is critical that each row of bit holders/blocks are not only welded precisely but that the proper support and wear plates are positioned next to or behind the holders. The bigger models actually have connecting support plates to minimize the chance of a block breaking even in the most extreme applications. Antraquip proudly conducts 100% of the fabrication of the drums in house, including the welding and stress relieving to ensure the highest quality standards and consistency. Moving hundreds of cutters per year requires so many drums that we employ a team of welders that are operating nearly 24 hours per day at our plant in Maryland.
The spur gears drive 2 separate output shafts (left and right) on which the drums/heads are mounted onto using clamping sleeves and bolt system which allows for easy access to the drums and shaft. The output shaft assembly is completely self-contained and sealed so there are no concerns for dirt, water etc. penetrating the gearbox which makes this design optimal for extreme conditions working under water or in mud and soil mixing applications as well. Another major advantage of this mounting system is that there is no greasing required for any of the Antraquip cutters.
All of the Antraquip hydraulic cutters utilize a low speed, high torque radial piston motor that transmits its power through the drive shaft, gears and output shafts. As Antraquip cutters do not use significant gear reduction in its transmission the hydraulic motor is rarely operating at or near its peak. Some models include gear reduction which then uses a smaller motor that is running at a higher speed to provide proper tip speed (ie. cutting speed) which leads to shorter life cycle of the hydraulic motor. As an analogy, consider the life of your car motor if running at 120mph at all times as opposed to 60mph. Antraquip does everything possible to protect and maximize the performance of its attachments with the use of stronger hydraulic motors relative to model size. Additionally, the hydraulic motors each have several displacement options to create the perfect match of hydraulic cutter on excavator based on available auxiliary oil flow. This component can be easily changed as needed, given easy access to hydraulic motor outside of gearbox itself.
All models of Antraquip transverse cutters (smallest to largest) utilize 3 rugged spur gears, powered by a low speed, high torque radial piston motor through a drive shaft (see illustration below). Why use spur gears and not a simpler, cheaper direct drive method positioning the hydraulic motor between the heads? There are several reasons Antraquip cutters chose this design:
The gears utilized in Antraquip cutters (as with the all other components being made in the USA) are manufactured by a reputable American gear manufacturer and is capable of sustaining forces well beyond what the certain model of cutter could generate.
The gearbox or housing itself is built with high quality steel with maximum wall thickness and wear plates installed to again achieve maximum life in the hardest of applications.
We recognize, you as a customer have many options, which is healthy for the marketplace but we appreciate you taking the time to read some of the details of the Antraquip hydraulic cutter design. We are a specialized company committed to maintain our rapid growth of this product and sector by offering the most reliable and productive attachments possible and are continuing the innovation process to do so. We are committed to the "Made in America" movement and are proud to conduct all of our manufacturing at our facility in Hagerstown, Maryland USA.
Please do not hesitate to contact us with any questions or request for additional details. I will leave you with a quick illustration of the layout for your reference and we look forward to hearing from you soon.