Brownfield conveyor projects are constrained by the building, not by the conveyor. In this Zhongshan warehouse, the floor was uneven by 40 mm across the conveyor route, the ceiling was 5.2 metres, and the operation could not stop for more than a weekend.
The requirement
The customer needed to move cartons from the receiving area to the dispatch area, a distance of 85 metres, without manual handling. The volume was 1,800 cartons per shift, with a peak of 300 per hour. The existing operation used forklifts and manual carts, which caused congestion and damage.
The building had columns every 6 metres and a mezzanine over part of the route. The conveyor had to pass under the mezzanine, which left 2.8 metres of clearance.
The survey
We surveyed the floor with a laser level and found a 40 mm variation over the route. A conveyor frame that followed the floor would have had a slope that caused cartons to slide and accumulate against the guide rails. We designed the frame with adjustable feet and a separate support structure that was levelled independently of the floor.
We also surveyed the columns and found that two were 80 mm out of line. The conveyor route was adjusted to avoid them, which added 4 metres to the length but removed the need for a custom support.
| Constraint | Finding | Solution |
|---|---|---|
| Floor level | 40 mm variation | Independent levelled frame |
| Ceiling | 5.2 m, mezzanine 2.8 m | Low-profile conveyor |
| Columns | Two out of line | Route adjustment |
| Operation | Cannot stop | Weekend installation |
The conveyor
We used a modular powered roller conveyor with a 50 mm roller and a 100 mm pitch. The frame was 200 mm deep, which gave the low profile needed under the mezzanine. The conveyor was split into four sections, each with its own drive, so that a failure in one section did not stop the whole line.
The sections were pre-assembled and tested in our plant, then disassembled into modules that could fit through the warehouse door. The modules were numbered and tagged to match the layout drawing.
Installation sequence
Weekend one: install the support structure and the first two sections, connect the power and test. Weekend two: install the remaining sections, align the transfers and commission the whole line. The customer's maintenance team was trained during the second weekend.
The key to the weekend installation was the pre-assembly. Every module was tested in our plant, and every cable was labelled. The site work was assembly, not fabrication.
What was difficult
The floor anchors were the biggest surprise. The existing floor had a hard top layer that dulled the drill bits, and two anchors hit rebar. We switched to a chemical anchor for those positions, which took longer but held properly.
The second issue was the mezzanine clearance. The conveyor was 2.75 metres high at the highest point, which left only 50 mm under the mezzanine beam. We lowered the conveyor by 100 mm and adjusted the incline, which gave 150 mm clearance.
Lessons
Survey the floor and the columns before designing the conveyor. A 40 mm floor variation is not unusual in older buildings, and it will affect the conveyor if the frame follows the floor. Pre-assemble and test every module; site fabrication is the enemy of a weekend installation.
Frequently asked questions
Can the conveyor handle the existing carton sizes?
Yes, the roller pitch and width were selected for the carton range. The smallest carton was 200 mm long, which required a 100 mm pitch.
What about future expansion?
The conveyor has two spare drive sections and a reserved connection point for a future extension to the packing area.
How was the operation kept running?
The installation was phased over two weekends, and the temporary route used the existing forklifts. The customer planned the inventory to cover the reduced capacity.
If you are retrofitting a conveyor into an older building, send the floor survey and layout to our engineers through the contact page.
