There are a number of different versions of scraper winch machines in everyday use and the most common designs are those that are derived from the old Joy-Sullivan.
They use two drums and an electric motor in an in-line arrangement. The motor drives the pull drum via a gearbox, while the change of the direction of the pull is done by applying a breaking force via clutch bands onto the surface of the clutch gear which is adjacent to the drums. The pull force and velocity vary with the effective drum diameter and these parameters are continually changing with the change of the amount of rope wound on the drum. When the rope velocity is the highest, the pull force is the lowest and vice versa.
Scraper winches are powered by low voltage squirrel-cage alternating current motors. They are purposely designed and built to operate at larger slip angles, due to the variable loading that they experience during the cleaning / ore scraping process.
Operating a Scraper Winch Safely
Factors to be considered on how to operate a scraper winch safely and at optimal levels entail the allocation of the correct scraper winch to the job. Since there are various types of scraper winches on the market for various applications, the correct one needs to be selected. The distance to be travelled by the ore, the space allocated for the winch and how big the load to be pulled by the winch should also be considered.
The correct installation of the snatch block is key to the performance of the scraper winch in order to avoid safety related issues and the ability to run the scraper with winch correctly. The daily maintenance of the winch is critical, while general maintenance prolongs the life of the winch. In addition, the winch driver needs to be correctly trained in the use of the winch effectively and safely, and on how to use the correct check list to inspect the winch before and after shift start and ends.
Choosing the Right Scraper Winch for the Job
One needs to establish what the load weight that the winch will be required to pull, the distance the winch will be required to pull the load, the space available to mount and operate the winch and the safety consideration that need to be taken into account
After selecting the correct winch and it is ready for installation there are a number of factors that should be taken into consideration. The winch must be mounted on a flat concrete surface in order to minimise vibrations of the winch. The winch must be pinned down with winch holding clamps and six holding down bolts. In addition, the winch must stand at a 90degree angle to the snatch block with the steel cables running over the drums of the winch and the scrapper must be able to move between the snatch block and the winch.
The industry has evolved over the years as a result of new technologies and the continuous research and developments within the scraper winch industry. The industry has seen the use of different types of machines in workshops, streamlining of production lines, the use of computers and robots to cut, bend and weld steel. The past two years has experienced the development of a semi-automated scraper winch that works via a remote control, a fully automated scraper winch including the design of new safety technologies on the scraper winch itself, says Justin Boone, Health and Safety Manager, from Bafotech (Pty) Ltd.
Electrical or Hydraulic
According to Boone, an electrical driven scraper winch is the best, since it is easier to maintain and repair, and less space is required during the installation and operation phases. However, each individual client has their preferences and the industry is able to supply both types of motors for winches.
Bafotech: One Stop Scraper Winch Shop
Bafotech (Pty) Ltd previously known as Tech-Kraft (Pty) Ltd has been in existence for more than 30 years. The company was founded by the Boone brothers- Frans, Chris and Pat who is the current CEO. Bafotech manufacture, repair and assemble all parts used on all scraper winches under one roof and are also the OEM standard holders of all Joy Sullivan scraper winches as well as the Bafotech Mono Winch.
“We deal with many mining houses and we always guarantee to our clients and customers- that we will offer you a quality product at a quality price”, stated Boone.