Overall Length Calculation

Maxi-Bolt part numbers are written using the following format:

MB-Diameter Series-Overall Length-Sleeve Length

Where Diameter Series is one of 250, 375, 500, 625, 750, 1000, or 1250 indicating, respectively, a 1/4", 3/8", 1/2", 5/8", 3/4", 1" or 1 1/4" diameter stud bolt.

Overall Length denotes the total length of the stud bolt.

The anchor's Sleeve Length is generally equal to the anchor's embedment, except where a type II installation requires bringing the sleeve above the surface of the concrete to extend through a base plate or fixture.

Procedure

The Maxi-Bolt is set by forcing the expansion sleeve to move laterally into the undercut portion of the hole. The baseplate or equipment is then set in place, the nut and washer are placed onto the Maxi-Bolt, and the anchor is then tensioned. The user needs to ensure there is a sufficient amount of threads available for setting and tensioning, and then use the larger of the two as the anchor's overall length.

1/4", and 3/8" Maxi-Bolts

The 1/4", and 3/8" Maxi-Bolts are usually manually set using a hand bolt setter, and tensioned using a torque wrench. The standard 1/4" Maxi-Bolt comes with an overall length of 4 1/4", and the standard 3/8" Maxi-Bolt comes with an overall length of 6". Non standard lengths are available. Please contact your Drillco representative.

1/2", 5/8", and 3/4" Maxi-Bolts

The 1/2", 5/8", and 3/4" Maxi-Bolts are usually manually set using a hand bolt setter, and tensioned using a torque wrench.

Manual Setting
Overall length for MB-500 = 1.7" + EMB. + GRIP
Overall length for MB-625 = 1.9" + EMB. + GRIP
Overall length for MB-750 = 2.4" + EMB. + GRIP

Manual Tensioning
Overall length for MB-500 = 1.1" + EMB. + GRIP
Overall length for MB-625 = 1.2" + EMB. + GRIP
Overall length for MB-750 = 1.4" + EMB. + GRIP

EMB - Length of bolt to be embedded in concrete. (inches)
GRIP - Combined thickness of all plates, attachments and/or grout pads needed for final installation. (inches)

Notes:
1.) If the anchor is to be set or tensioned prior to or in the absence of the grip, then GRIP = 0
2.) Anchors can also be set and tensioned hydraulically.

Example:

An A193 B7, 1/2" Maxi-Bolt is set in the concrete manually with a hand bolt setter. Then a 5/8" plate will be placed over it with no grout. The Maxi-Bolt will then be tensioned manually with a torque wrench. The anchors embedment is 7".

Overall length needed to set = 1.7 + 7 + 0 = 8.7"
Overall length needed to tension = 1.1 + 7 + .625 = 8.725"
Use the higher number 8.725", and the next inch increment for 1/2" Maxi-Bolts is 9 1/4".

The part number would be MB-500-9 1/4-7.

Example:

An A36, 3/4" Maxi-Bolt is set in the concrete manually with a hand bolt setter. Then a 3/4" plate will be placed over it with 1" of grout. The Maxi-Bolt will then be tensioned manually with a torque wrench. The anchors embedment is 9 1/4".

Overall length needed to set = 2.4 + 9.25 + 0 = 11.65"
Overall length needed to tension = 1.4 + 9.25 + .75 + 1 = 12.4"
Use the higher number 12.4". The next higher integer is 13".

The part number would be MBA36-750-13-9 1/4.

1" and 1 1/4" Maxi-Bolts

The 1", and 1-1/4" Maxi-Bolts are usually set and tensioned hydraulically.

Hydraulic Setting
Overall length for MB-1000 = 4.0" + EMB. + GRIP
Overall length for MB-1250 = 5.0" + EMB. + GRIP

Hydraulic Tensioning
Overall length for MB-1000 = 2.75" + EMB. + GRIP
Overall length for MB-1250 = 4.0" + EMB. + GRIP

EMB - Length of bolt to be embedded in concrete. (inches)
GRIP - Combined thickness of all plates, attachments and/or grout pads needed for final installation. (inches)
Note: If the anchor is to be set or tensioned prior to or in the absence of the grip, then GRIP = 0

Example:

A 1 1/4" Stainless Steel (304 Class 2) Maxi-Bolt is set in the concrete with a hydraulic ram. Then a 2" plate will be placed over it with 2" of grout. The Maxi-Bolt will then be tensioned with a hydraulic ram. The anchors embedment is 20".

Overall length needed to set = 5" + 20" + 0" = 25"
Overall length needed to tension = 4" + 20" + 4" = 28"
Use the higher number 28.

The part number would be SAMB-1250-28-20-304class2.

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