Chapter 6 Handling

6.4  Operation Machinery

Material handling equipment is mechanical equipment used for the movement, storage, control and protection of materials,goods and products throughout the process of manufacturing, distribution,consumption and disposal. The different types of material handling equipmentcan be classified into four major categories: transport equipment, positioning equipment, unit load formationequipment, and storage equipment.

The following are the typical operation machineries during material handling process:

(1) Lift trucks

Lift trucks also called forklifts can moveloads of master cartons both horizontally and vertically but are not limited tounit load handling. Skids or boxes may also be transported depending upon thenature of the product.

Many types of lift trucks are available.High-stacking trucks are capable of up to 40 feet of vertical movement. Palletless side-clamp versions are available for handling bulky product withoutpallet or slip-sheets. Other lift truck variations are available for narrowaisle and side-loading operations. Particular attention to narrow-aisle lifttrucks has increased in recent years, as warehouses seek to increase rackdensity and overall storage capacity. The lift truck is not economical forlong-distance horizontal movement because of the high ratio of labor per unitof transfer. It is most effectively utilized in shipping and receiving and toplace merchandise in high cube storage.

(2) Walkie-rider pallet trucks

Walkie-rider pallet trucks provide alow-cost, effective method of general materials handling utility. Typicalapplications include loading and unloading of transportation equipment, orderselection and accumulation and shuttling loads over longer transportationdistances throughout the warehouse. Walkie pallet tracks are widely used ingrocery warehouses.

(3) Towlines

Towlines consist of either in-floor oroverhead-mounted cable or drag devices. They are utilized to provide continuouspower to four-wheel trailers. The main advantage of a towline is continuousmovement. However, such handling devices have far less flexibility than lifttrucks. The most common application of towlines is for order selection. Orderselectors place merchandise on four-wheel trailer that are then towed to theshipping dock. A number of automated decoupling devices are available to routtrailers from the main towline to the shipping docks.

(4) Conveyors

Conveyors are used widely in shipping andreceiving operations and form the basic handling device for a number of orderselection systems. Conveyors are classified according to power, gravity, androller or belt movement. In power systems, the conveyor is powered by a drivechain form either above or below. Considerable conveyor flexibility issacrificed in such power configuration installations. Conveyor are effective inthat only the product is moved, eliminating the need for a movement unit toreturn.

(5) Carousels

A carousel operates on a different conceptthan most other mechanized handling equipment. Rather than requiring the orderselector to go to the inventory storage location, the carousel moves inventoryto the order selector. A carousel consists of a series of bins mounted on anoval track or rack. There may be multiple track levels, allowing for veryhigh-density carousel storage. The entire carousel rotates, moving theselection bin to a stationary operator. The typical carousel application is theselection bin to a stationary operator. The rationale behind carousel systemsis to shrink order selection labor requirements by reducing walking length and time.

(6) Robotics

The Robot is a humanlike machine that can beprogrammed to perform one or a series of functions. The appeal of robotics liesin the ability to program functionality based on expert systems using decisionlogic to direct the handling process. The popularity of robotics resulted fromtheir widespread adoption in the automotive industry during the early 1980s inan efforts to automate select manual tasks. The primary use of robotics inwarehousing is to build and break down unit loads. In the breakdown process,the robot is programmed to recognize stacking patterns on unitized loads andplace products in the desired position on a conveyor belt. The use of robot tobuild unit loads is essentially the reverse of breakdown. Another use roboticsin warehousing occurs in environments where it is difficult for humans tofunction.