Acrow Prop Safe Installation Guide

Acrow Props is an extremely versatile product that can be found on many construction sites. They are commonly used on construction sites to provide a quick and simple method of providing temporary support for reinforced concrete floor and beam formwork. Acrow struts are equally useful as raking struts to support column, wall, and stair formwork. They are invaluable in repair, demolition or permanent support replacement work, to support canopies, lintels and the like while brick or concrete work is setting.

Acrow struts consist of two circular steel tubes, an inner tube with a top plate that slides up and down freely within an outer tube that is attached to the base plate. The inner tube has holes along its length so you can quickly extend the inner tube to just below the desired height and insert a steel pin to lock at that length. To extend the strut to the correct height, the top of the outer tube is threaded and a collar, which is similar to a nut on a bolt, lifts and supports the steel pin. Then, as the collar is rotated and moved upward, the inner strut is extended. This allows you to achieve the exact height required.

The ‘Acrow Accessory Safe Installation Guide’ gives you a checklist of what to check even before you start and then shows you what you need to check to ensure the safe installation of your acrow accessories. Once installed, there is a list of items that should be reviewed regularly to ensure the continued safe performance of your acrow fixture installation and then ends with a checklist for safe removal.

Pre-installation checklist

• Start by planning the work. Make sure you have the correct number and size of accessories. Inspect the site and, if necessary, mark the locations of the accessories.
• Have you correctly selected the right size accessories for the job? Do you have enough to support the weight? Never exceed the Safe Working Load (SWL) for your specific size struts. Consult manufacturers’ load charts. If you are unsure, consult your engineer or other responsible person, who will consider the weight of the aerial structure to be supported and determine the correct size and quantity.
• It is the user’s responsibility to check the accessories every time they start working. When inspecting accessories, items to check include: –
  • Check that the inner and outer tubes are straight and slide easily.
  • Check that the collar rotates freely around the thread and that the tread is not damaged or blocked.
  • Check to make sure there is no damage to the pin. If the pin is secured with a chain, make sure it is still attached. If it is equipped with a wrap pin, it is not necessary to secure it with a chain. Only use the original pin, do not use any other pin.
• Do not try to repair any defective accessories. If a propeller is defective, it should be tagged and isolated immediately and should not be used.

Installation checklist

• Warning struts that are designed to be used in compression CANNOT be used in tension.
• Always wear the proper safety equipment when using this equipment.
• Make sure the work area is cordoned off to prevent public access, only essential people should work in the area.
• Make sure the struts are installed by qualified people who have the necessary knowledge and experience to do the job safely.
• It is important that the strut is installed vertically to ensure that it can support its specified load. Accessories should never be used more than 1.5 degrees from vertical, as this can substantially decrease their capacity. This is approximately 2 inches (50 mm) from true vertical for every 6 feet (1.8 m) of length.
• Make sure the base plate and top plate of your propeller are resting directly on the surface. Also make sure that the floor and ceiling surfaces are strong enough to support the weight that will be placed on them.
• When the struts are supported by a flexible surface, such as a gravel surface, each strut must be supported by a wooden sole or equivalent. A wooden sole should be at least 9 inches (225 mm) wide by 1.5 inches (38 mm) thick. It should be long enough to protrude at least 300 mm (1 ft.) On each side of the strut base plate. A sole can also be worn over the head plate to help distribute the load if necessary. If you are unsure or in doubt, consult your engineer or other competent person.
• Acrow struts come in 5 different sizes, so don’t use accessories that are too short when compensating for the space with wood. Always use the correct length Acrow accessory.

Post-installation checklist

• Struts left to support a curing slab can loosen over time. As the slab cures, it naturally contracts, which can cause the strut to loosen, so it is recommended that a competent person inspect and retighten them regularly.
• At a minimum, all accessories should be inspected at least once a week.
• Make sure the area is safe from the general public if accessories are to be left in place unattended.
• Do not string or tie anything to accessories.

Accessory Disposal Checklist

• Start by planning the work.
• Always wear the proper safety equipment when using this equipment.
• Make sure the work area is cordoned off to prevent public access, only essential people should work in the area.
• Make sure accessories are removed by qualified persons who have the necessary knowledge and experience to do the job safely.
• Do not remove or adjust any accessories until you are sure it is safe to do so.
• Always return the equipment to the rental company in clean condition.

Always seek professional advice before undertaking any shoring / shoring project. A shoring job that goes wrong can be disastrous, life-threatening, and an extremely expensive exercise to repair.