Concret Anchor Guidelines

Benner-Nawman is the master distributor of Sanko "Grip" anchors in the United States. The company is expanding and now own three factories in two countries. Sanko is the number one producer of concrete anchors in Japan and is known world wide for high quality products. With the experience of Benner-Nawman in the construction industry the progression to concrete anchors is natural. Benner-Nawman is offering many choices of concrete anchors, numerous varieties and sizes. There are also numerous types of material used to make them. In this article we will cover different types of concrete anchors and the types of material used to make them as well as how to install them for proper installation and usage.

The CT drop in anchor is threaded internally for the controlled anchor expansion built to .03 mm tolerance in expansion deferential. To be used with setting tools for full arc expansion. This anchor recessed in concrete and if no longer needed can be removed and the hole filled in with concrete and smoothed. They are suitable for flush mounting applications. The GT type anchor is also a drop in anchor system similar to the CT. The main difference is the GT is designed with a lipped top for a semi flush installation into concrete. Four main points to consider when using drop in anchors are as follows:

1. Recessed- Drill the hole the same length as the anchor for a flush finish.
2. Versatile-Will work with bolts and threaded rod in any length.
3. If the anchor is no longer needed, simply plug or fill with cement to make the surface smooth again.
4. The inside threads are machine rolled instead of cut for superior holding strength.

The CT anchor was originally developed by Sanko for the 1964 Olympic Games. The CT "all anchor" pioneered the hammer-driven type anchor. Simple and effective design allows the anchor to expand in concrete and masonry just by hammering down the hardest steel center pin. By hammering in the pin no torque wrench is required to set it.

The HAS weld anchor is used with an external bottom bearing expansion plug. It is designed to be used by hammering in with attachments by direct welding. This is a simple anchor system that leaves a weld stud exposed or use. This anchoring method is ideal for installation of window, shutter, and door framework. Simply drill a hole, insert the anchor, and hammer into place to set the anchor. Hammer drive anchors feature hardened center pins, driven in for anchor expansion; it includes nut and washers that can be for various settings and depths. Installation is simple and dept of hole is not critical and no tools required. Just hammer the pin in, the anchor tensions automatically. The anchor is set when the center pin is flushed with the top of the bolt making it easy to inspect.

Masonry anchors have come along way over years. It used to be to attach anything to concrete walls was a major chore with new advancements most can be "DIY" (do it yourself) with average tools. There are three different types of masonry anchors mechanical, powder-activated, chemical. A chemical anchor is not used unless your are building a bridge and then specific certifications are needed.

Masonry anchors work in two ways by expanding against the side of a hole and gripping the concrete or by friction against the sides of the hole. The holding sustainability of any anchor will depend on one the quality of concrete and two the placement or position of anchor. Old and crumbly concrete will have weak holding power likewise if anchors are placed near edges or anchors are placed to close together the generated force can break the concrete. General recommendation is on any anchor that it should be no closer than 5 diameters from the edge. Two anchors shouldn't be placed closer than 10 inches in diameter from each other.

The most important factor in choosing proper anchors is the type of load it can carry. Anchors are rated for two types of loads, shear work loads (whether fit of the fixture exerts force parallel to the surface of concrete). Tensile loads are caused when the fixture exerts force perpendicular to surface. Other load factors include static loads that are steady and constant for example circuit breaker boxes fastened to basement wall or sides of home. Dynamic or vibrating loads that are constantly changing. For example you have hung a wall shelf from a concrete wall to mount an electric grinder; the load on the anchors will be a dynamic load. You also have impact loads that change suddenly for example a box onto a shelf that's anchored to wall. Standard recommendation is that any anchor if chosen be rated for four times the weight it will carry. It's recommended that you watch any anchor installation videos for any DIY (do it yourself) project to follow the step by step instructions by the manufacturer. When choosing anchors the total load should be divided by the number of anchors that will carry weight.

When installing any type of anchor a hammer drill is recommended to drill the holes. Most anchors are made to go into concrete and not brick or block. The size of the hole must equal the size of the anchor that you are using. Drill the hole with the hammer drill, prior to drilling it is recommended that you determine the size needed by setting the hammer drill to that particular size or a piece of tape can be placed onto the drill bit to make sure you do not go deeper. Once done, drill the hole that is needed. It is recommended that proper eye equipment be used at all times when drilling. The hole once drilled must be cleaned of all concrete dust particles prior to installation of the anchor. This can be done by using a wire brush or compressed air vacuum to clean hole of debris. Once done then the anchor can be installed. A hammer drill is recommended to drill any and all holes. Masonry drill bits work by chipping the concrete away (as opposed to wood bits, which will cut wood away). If you use any standard electric drill you will find that the drill works slowly and can cause you to have a larger hole than needed or intended. For any concrete anchor to be effective the hole must be exact in diameter and in some case depth as well for the anchor to fit properly.

Masonry anchors come in four basic types; concrete screws, hammer anchors, one piece expansion , two step expansion that's used with standard screws. They are called two step screws because before installed inside the hole it must be spotted, due to the anchor being larger than fastener that will go into it. You'll have to position the material that's to be anchored and spot the location of the hole, then setting the material aside to drill and then insert the anchor. Finally you can place the material in position and fasten it down. An advantage to these anchors is the screws can be removed then reinserted and they're inexpensive.

One piece expansion anchors, two step anchors are in past but two types of 1-piece anchors is still popular. Sleeve anchors have a steel sleeve on the shank that is split at the bottom of the anchor for expansion. Once placed or installed sleeve anchors can't be removed. They do come in a variety of heads, a hex head, acorn nut, or either flat head screws or round screws.

The shank of a wedge anchor is similar to a sleeve anchor, threaded at the top and with a cone shaped plug at the bottom. The shank of a wedge anchor grooved on opposite sides. In each groove lies a rectangular shank with a spaded shaped wedge on its end. As the nut is tightened the anchors washer pushes the rectangular shanks down, which spreads the wedge over the plug. Also like the sleeve anchor, the wedge anchor cannot be removed once installed. They also always have a hex head with a washer so the material can be removed and reinstalled. To install anchor, wedge or sleeve, first position the material that is to be anchored. Drill a hole in the masonry behind the bolt hole. Make sure the specified diameter, it is recommended that at least º" deeper than the length of the anchor. Insert the anchor in the hole and tighten a sleeve anchor two to three turns to expand it. Tighten a wedge anchor three to five turns.

There are no rules about which anchor to use in what situation but some helpful guidelines are available. To attach machinery to a concrete floor you want to use a heavy expansion anchor such as a sleeve or wedge anchor. Framing around a door or window opening it's recommended that hammer anchors be used. Shelf brackets on a foundation wall the use of concrete screws are generally the best choice because they can be removed if necessary. If installing a conduit to a foundation wall, it is recommended that you use hammer anchors or concrete screws. Applying mudsill to a foundation use a sleeve anchor for an occasional missing anchor bolt, if starting from scratch and there are no bolts use either sleeve anchors or wedge anchors.

The following tools and material checklist may be helpful for those who are new to concrete anchors. Have a steel measuring tape available. Secondly, a hammer drill as mentioned above. Lastly have other tools available like a hammer, screwdriver, and drill bits.

The Concrete Sawing and Drilling Association recently sponsored a research study at the University of Toledo on several different drop- in anchor manufacturers including Sanko, Hilti and Red Head. In this study the Sanko anchors was matched up against the other popular anchors in the market. Sanko anchors were found to support approximately 15 % more weight than the competition.

Sanko has over 40 years of experience manufacturing concrete anchors. In addition to this, Sanko has a stringent quality assurance process. This along with the support of Benner-Nawman as your U.S. connection makes the Sanko anchor the best in the business. Our anchors are in stock and ready to buy online.

Benner-Nawman would also like to mention the "Bucket Concept". The Sanko Anchor Bucket is stocked with everything you will need to install Sanko drop-in anchors. Portable, the Sanko Anchor bucket is perfect for job sites. The bucket includes (500) CT or GT drop in anchors, also Sanko's SDS-plus drill bits, and the setting tool.

The Sanko drill bit is specially designed for the Sanko fasteners. It has four blades on this drill bit to create a more precise circular hole than two blade bits helping the anchor have a better base for setting. The four blades reduce drilling time by about 15%. The Sanko drill bit blades are carbide reinforced and are of a durable construction which allows it to last longer than the competition. The drill has depth gauges on which are specifically designed for Sanko anchors. These depth gauges show you exactly how deep to drill in order to set your anchor.

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