Yes, it is called Nitrile (NBR, Buna-N) - Acrylonitrile-butadiene. Trade names: Breon, Butaprene, Chemigum, Chemivic, Elaprim, FR-N, Hycar, Krynac, NYsyn, NYsynblak, Paracril, Paracril OZO, Perbunan N, Tylac, Nipol. It has very good resistance to oil and gasoline; superior resistance to petroleum-based hydraulic fluids; a wide range of service temperatures (-65 to 300°F); and a very good resistance to alkalis and acids. It has inferior resistance to ozone, sunlight and natural aging; and a poor resistance to oxygenated solvents. Nitrile and neoprene are the highest-volume oil-resistant elastomers. Nitrile is superior to neoprene in resistance to oil, gasoline and aromatic solvents. However, it does not perform as well as neoprene in applications requiring exposure to weather, ozone and sunlight. Furthermore, it has no inherent flame resistance. As the acrylonitrile content of the elastomer increases, oil and solvent resistance and abrasion resistance improve. When the acrylonitrile content decreases, these properties deteriorate, and low-temperature flexibility and resilience improve.

Can A-LOK connectors be used with concrete pipe?

Yes, A-LOK connectors can be used with all types of round smooth-wall pipe.

How long can A-LOK rubber connectors be stored outside at our plant or on the jobsite?

The rubber compounds we use have an anti-ozant mixed in that helps it resist light. They also have a anti-oxidant that helps it resist air. When you see a rubber connector that has been out in the light and air for awhile it will have a dullness to the finish as well as slight brownish cast. This is nothing more that the two above mention compounds coming to the surface to protect the rubber. So, a couple of months outside is alright but much longer than that and you may see some cracking. ASTM specs say store rubber inside, at 70 degrees. One additional way to add protection is to use Armor–All since it has very good UV and ozone protection.

Can the same size A-LOK compression style connectors be cast into different size manholes or are the connectors different like the mandrels?

The A-LOK compression connector fitting properly is based initially on pipe OD, so whether the same size pipe goes in a 48'' manhole or a 60'' manhole, the only thing that changes is the curve of the connector created by the mandrels to fit close to the center of the wall to achieve proper embedment of the “T”/waterstop of each connector. The opening for the pipe OD, also know as the “A-LOK connector /mandrel ID”, remains the same regardless of the curve.

How do I use the torque wrench?

Click here for detailed instructions.

Can a flatwall gasket be used on a roundwall structure, or vice versa?

No, there are different cut lengths for round and flat wall connectors. All of our flatwall connectors are labeled "FW" with a yellow stripe.

What is the temperature resistance for A-LOK gaskets?

Our EPDM rubber molded connectors can handle a reasonable constant temp of 250-270° F. Our extruded polyisoprene connectors can handle a reasonable constant temp of 150-160° F. Nitrile rubber connectors can handle a reasonable constant temperature of 230-250° F.

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Connector Repair

How do we repair A-LOK compression connectors when they leak?

Most importantly, be sure the manhole is safe to enter.

1. Check for debris trapped in between connector and OD of the pipe. If debris are found remove them by running a thin trowel in between the connector and the pipe.

2.Inflate the connector if it is not tight to the pipe.

Use urethane grout material, AV-202, to stop the leak.

What if a splice on a connector seperates or breaks?

The connector should be replaced.

What if the contractor tears an A-LOK compression connector before or during installation

Call A-LOK at 1-800-822-2565, it may be able to be repaired

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Mandrel

Do you need mandrels for every size pipe?

Yes, unless the difference between the pipes OD's is plus or minus ¼''.

How long does a fiberglass mandrel last?

Depending on how much it is used, if it's cleaned and oiled after use and removed from the structure with a dead blow hammer. There is no telling how long it can last.

What determines equipment delivery time?

-If it is a stock or non stocking item.

-The quantity ordered 1 or 100.

-Is it a size we have made in the past or is it a brand new size?

-The travel time from our plant(s) to yours.

-How many orders are already in house at the time your order is placed.

Why is there a flat spot on the mandrel?

The flat spot helps center pipe, over 18 inches in diameter, and a compression connector for installation. The flat spot should always be on the outside and towards the bottom of a manhole.

What is a good way to organize and store mandrels?

Mandrels should be matched in pairs organized by size using our Mandrel Storage Hooks.

What size hole do I need to drill if I am bolting the mandrels to the form?

You will need to drill a 13/16 of an inch hole.

Can one size mandrels be used with more than one size connector?

No.

Should we use air wrenches to tighten mandrel halves?

Yes you can, but the important thing is the nuts and bolts should be snug together. If they are too tight it could push connector out of the cavity and change the wall thickness.

What does the mandrel's part number refer to?

For example: AM-0610-048-05W-FM translates to AM= A-LOK Mandrel, 0610= A-LOK mandrel size, 048= inside 48”dimension of the ROUND structure the mandrel is made to fit, 05W= 5”wall thickness, FM= the mandrel is outfitted with openings for magnets to hold it in place during the pour (these mandrels could also be wired in place).  Another example on part AM-1430-F12, the F12= 12” flat wall structure. 

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Installation

How close can I put two holes in a manhole using A-LOK compression connectors?

Half the distance of  the smallest pipe OD measured from the outside edge of one mandrel to outside edge of the other mandrel when placed on the core area.

What distance can an A-LOK compression connector be placed from the manhole spigot?

6 inches, plus the joint.

What distance can an A-LOK compression connector be placed up from a manhole base bottom?

2-4 inches.

Can a contractor push the pipe in and out of an A-LOK compression connector?

Yes, if the pipe is beveled and lubed and properly centered in the pipe, but it's not recommended.

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