Open springs combined with snubbers

Additional snubbers may be required. See the manufacturer’s instructions.

Step 1: Determine where to bolt the equipment

Accurately draw the bolt pattern for the open spring mounting plate on the floor or pad using one of the following methods:

• Set the equipment in place and mark the holes.
• Make a template.
• Use measurements and shop drawings to lay out the bolt hole pattern.

Step 2: Install post-installed anchors for open springs only (snubbers are covered in later steps)

Drill and install post-installed anchors for spring isolators

Step 3: Attach open spring isolators to concrete floor or pad with anchors installed in step 2

Set isolator, apply nuts and torque. Use bolts for shell-type anchors or internally threaded wedge or chemical anchors. Install according to the anchor manufacturer’s instructions.

BE CAREFUL NOT TO DAMAGE THE ANCHORS WHEN SETTING THE ISOLATOR.

Step 4: Set equipment on open springs

Set equipment on isolators but do not level or torque attachment nuts.

Equipment must have a structural frame capable for point load at the open spring isolators.

Some installations require the base to be concrete-filled. See Figure 122 for a typical concrete-filled installation.

Coordinate the location of equipment attachment points and snubber attachment points before filling with concrete.

Step 5: Determine where to attach snubber

A snubber has two assemblies: the snubber equipment assembly and the snubber base assembly.

Level the equipment. Final leveling will be required in later steps. Accurately draw the bolt pattern for the snubber mounting plate on the floor or pad and on the equipment.

All snubber clearance requirements for aligning the snubber must be met. Shims may be provided.

Step 6: Attach snubber equipment assembly to equipment

Attach the snubber equipment assembly to the equipment by bolting it to embedded bolts in a concrete-filled base (see Figure 122), or by bolting or welding to a steel base.

Step 7: Determine where to bolt snubber base

Accurately draw the bolt pattern for the snubber mounting plate on the floor or pad.

Step 8: Drill and install post-installed anchors

See Anchors

Step 9: Raise the equipment

Raising the equipment allows the snubber base assembly to be placed over the anchors installed in Step 6.

Step 10: Lower the equipment

Level equipment and connect the two snubber assemblies as specified in the manufacturer’s instructions. Verify that spacing requirements are met. Complete final attachment to open springs.

DO NOT INSTALL THE ISOLATOR OR SNUBBERS IN ANY CONFIGURATION OTHER THAN THAT SHOWN IN THE MANUFACTURER’S INSTRUCTIONS.

The equipment is now installed to resist earthquakes. Flexible piping connections, flexible ductwork connections, and flexible conduit connections must be used when connecting systems to isolated equipment.

Figure 123 is an example of the requirements for flexible system connections.