Safety Features Within VRCs

Image courtesy of MHI

Vertical reciprocating conveyors offer one of the safest methods for moving goods and materials between levels.

This article first appeared in an MHI blog.[1]

The priority of any material handling operation in a manufacturing facility is safety. Vertical Reciprocating Conveyors (VRCs) are commonly used to move materials between different levels, but they are also widely used to interface with other manufacturing equipment. Both uses can require an increased focus on safety. You not only want to protect personnel using the equipment, but also the materials as they are being transferred.

Vertical Reciprocating Conveyors (VRCs) offer one of the safest methods for moving goods and materials between levels. All VRCs are required by ANSI/ASME B20.1 code to have enclosures and gates to protect personnel while the lift is operational, as well as the surrounding area within the facility. VRCs can also be integrated with various design options to enhance safety further for specific operational requirements.

ADVANCED SAFETY MEASURES

VRCs are used in a variety of production applications, including interfacing with other manufacturing equipment, from high-speed conveyors to robotics and automated guided vehicles (AGVs) that assist in loading materials onto the VRC carriage. Interfacing VRCs with other manufacturing equipment requires careful attention to safety. Safety measures may include proximity sensors, photoelectric eyes, or smart controllers to detect the presence of objects or workers and prevent unsafe conditions.

A further look into these specialized options:

Powered Deck Locks

When the VRC carriage arrives at the designated level, powered deck locks are controlled to automatically lock the carriage in place while loading/unloading or when maintenance work is carried out.

Automated Control Systems

To ensure smooth coordination between the VRC and other manufacturing equipment, an automated control system can be implemented. This system enables communication and synchronization between the VRC and other equipment, such as conveyors, robots or production lines. By integrating the control systems, you can establish protocols for timing, signaling and data exchange, allowing for efficient material flow and reducing the risk of bottlenecks or collisions.

Load Cells & Visual Light Indicators

While many VRCs can handle huge loads, it’s important to have a system in place that monitors potential overloads. Load cells can gauge and monitor load capacity while visual light indicators signal the operator when loads are approaching capacity. This not only creates a safe operation but protects the integrity of the equipment in the long run.

Proximity Sensors/Photo Eyes

Photo eyes and sensors are used to detect the presence of objects or materials on the VRC platform or in the surrounding areas. They emit infrared or laser beams and measure the reflection or interruption of these beams to determine if an object is present. This helps prevent the VRC from operating when there is an obstruction, avoiding collisions or damage to goods and equipment.

There are many options available to improve your safety requirements. It’s important to note that the specific interface requirements may vary depending on the equipment being integrated, and the unique needs of your manufacturing process. Consulting with VRC manufacturers can provide valuable insights and guidance tailored to your specific setup. WMHS

MHI’s Conveyor & Sortation Systems (CSS) group members are the industry’s leading providers of conveyors and sortation systems. They design, fabricate and install conveyor and sortation systems worldwide and in virtually every major manufacturing and distribution sector. To learn more about the MHI CSS industry group and VRC sub-committee, visit https://www.mhi.org/css.

[1] www.warehouseautomation.org

Safety Standards for VRCs

The ASME B20.1-2021: Safety Standard for Conveyors and Related Equipment is intended to provide the safe operation and maintenance of conveying equipment. It applies to the design, construction, installation, maintenance, inspection and operation of conveyors and conveying systems in relation to hazards. The conveyors covered by this standard can be bulk material, package, or unit-handling types installed for permanent, temporary or portable operation.

Conveyor types covered in the standard include: fixed belt conveyors, en masse conveyors, mobile conveyors, pusher bar conveyors and tow conveyors. Features that are addressed include: backstops, gates and switches, maintenance, lubrication, headroom, controls, operation and fire safety.

First published in 1947, as ASME B20.1, this standard is now revised every three years to keep it current. A recent change is text that was added to section I-3.9, “Gates and Enclosures,” indicating that enclosure height requirements apply “unless guarded by location.”

In addition to the conveyor types noted in the article and above, other types[1] include:

Aero-mechanical conveyor

Automotive conveyor

Belt-driven live roller conveyor

Bucket conveyor

Chain conveyor

Chain-driven live roller conveyor

Drag conveyor

Dust-proof conveyor

Electric track vehicle system

Flexible conveyor

Gravity conveyor

Gravity skate-wheel conveyor

Lineshaft roller conveyor

Motorized-drive roller conveyor

Overhead I-beam conveyor

Overland conveyor

Pharmaceutical
conveyor

Plastic belt conveyor

Pneumatic conveyor

Screw or auger conveyor

Spiral conveyor

Tube chain conveyor

Tubular Gallery conveyor

Vacuum conveyor

Vertical conveyor

Vibrating conveyor

Walking Beam

Wire mesh conveyor

[1]https://en.wikipedia.org/wiki/Conveyor_system