Making the Turn
“There’s no way that train of carts will make THAT turn!” Have you ever thought that? There are many assumptions made about tugged carts and what makes them effective at handling turns. Let’s explore that.
To properly understand, it’s critical that we first review cart types. The most basic option is a tugged cart whereby the cart is pulled directly by a tugger either singularly or with other carts. Another option is a mother/daughter cart system. Here, one cart (the daughter) rides on another (a mother cart) and it is the bottom cart that is pulled. [NOTE: The rider cart’s casters actually don’t touch the floor with the Jtec system. This is accomplished via strictly mechanical means with no worry of electrical or hydraulic failures.] A third option is a similar style but one in which the wheels of the secondary cart do maintain floor contact (e.g., a corral cart).
What are the options?
While there are various types of steering designs associated with these options, the four primary are: quad-steer, rear-steer, center-steer, and four-swivel casters.
To handle tight turns (6’ aisle-to-aisle for example), the best option is quad-steer whereby all four wheels work in unison with the front pair pointing into the turn and the rear two pointing away. A rear-steer configuration features two swivel casters on the push-handle end of the cart and two fixed casters on the opposite end. With a six-wheel design (i.e., center steer), the center two casters are fixed while the casters on the cart’s corners swivel. The fourth option, with four swivel wheels, is more difficult to control although it may allow for easier line-side placement where space is very limited.
In a mother/daughter cart system, the mother carts will most likely feature quad-steer while the daughter carts will be rear-steer although Jtec’s lower capacity mother carts (2,000 lbs) are center-steer. Tugged cart can be manufactured in a number of ways. For superior cornering and tracking, a quad-steer design is best; however, the other steering options are available. Four swivel casters is the least used as again, this design makes tracking and cart manipulation difficult.
To put the benefit of a Jtec quad-steer mother cart into perspective, there is only an approximate 12” drift into the turn for the fifth of five carts in tow at a 90-degree turn from an 8’ aisle to an 8’ aisle.