COMPANY PROCESS AND PROFILE
4.2 Product Description
Tank 3 (T3) and Tank 4 (T4) are rinse tanks which contain municipal water and are used to rinse off excess process solution from the surface of the workpieces. The preparation of these tank solutions will be discussed in Section 4.4.
Corner plate (see later)
Figure 4.5 Racking unit made from angled uprights
Diagonal bracing (see later)
Figure 4.6 Racking system made from standard uprights, horizontal and diagonal bracings
A beam is a bar which is transversely fitted in between two uprights that are placed a set distance apart. Beams support large items which rest directly on them or are loaded with pallets which contain stock items. Shelves, on the other hand, are permanently attached to the beams and items to be stored are placed directly on the shelves. Two types of beams are manufactured namely, open beams and closed beams. They are manufactured in different widths ranging from 60 mm to 146 mm. Pallets are platforms onto which goods or large items can be stacked and are designed so they can easily be transported by a forklift (see Figure 4.7). Shelving is used in conjunction with racking that is made from angled uprights. Shelving (see Figure 4.7) is referred to as 'deck panelling' where standard uprights are used to make the racking. Shelving is a fixed unit and cannot be removed from the rack system like the pallets can.
Figure 4.7 Racking system with pallets and shelves
The primary structures made from the three basic racking elements often have attachments fitted to them. These are designed to stabilize the racking system and will be referred to as secondary elements. The most common ones are listed and discussed below:
• bracings
• feet
• back-to-wall ties
• back-to-back ties
• cladding Sheets
• corner Plates
• hooks.
The steel frames, mentioned earlier, are braced with horizontal or diagonal configured straps to increase the load bearing capacity of the frame. Bracings are inserted between two uprights and fit into the internal channel of the standard uprights and thus add support to the structure. There are two types of bracings manufactured: diagonal and horizontal. These two names refer to the orientation of the bracing between the uprights (see Figure 4.6). The bottom of the uprights are often fitted with a foot to help steady the racking system and spread the load at the base. Some structures have fixtures called back- to-wall ties: which allow them to be bolted to the wall. Some structures have back-to- back ties, which are used to secure individual racking systems to one another. Panels, called cladding sheets are made and fitted across the bottom of the racking frame to protect it from damage caused when, for example, forklifts bump into the racks. Corner plates are small inserts between the shelf unit and the upright it is attached to, and these plates enable the shelf to be attached to the upright. Hooks are small units that are used to attach beams to the uprights without bolting and are shown in Figure 4.8.
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Figure 4.8 Extended racking system with hooks
Industrial racking systems are made from many uprights that are placed a specific distance apart and are joined together by (horizontal) beams. The beams are attached to the uprights by means of bolts or hooks. The main racking systems manufactured by the company include Mobile, Live Storage, Drive-in and Cantilever. The Mobile Racking systems are made from racking frames that are not in a fixed position. The bottom of the uprights are fitted with wheels which sit in a channel, so that the racking can be easily moved into and out of position, thus closing and opening the aisles between adjacent frames. This type of racking is used mainly to save space when storing items. The frames in the other racking systems are in fixed positions. The Live Storage Racking system is made from racking in which pallets sit on a moving shelf. The pallets are stacked on a roller system which allows the stored items to be automatically moved along the length of the racking. The aisles between the frames are effectively redundant here as the forklift trucks lift items from the short (braced) end of the frame rather than from along its length. The Access Drive-in Racking systems are different from that of Live Storage but similar to Mobile or Drive-in. The forklift trucks moves in between the frames to pick up
loads from the length of the racking. The drive-in racking is made from uprights that are 211m long and 3 mm thick and has a design that creates a very high-density storage for loads that cannot be stacked on top of each other.177 Cantilever Racking systems are made from uprights and cantilever arms that are place at either a 90° (straight arms) or a 60° angle (inclined arms) to the uprights. Straight arms are used for storing stable loads such as lumber, steel, cartons and skids. Inclined arms are used for cylindrical objects or loads that tend to roll forward.178 The uprights are present only on one side of the racking system.