Taboos for using expansion nails that must be known before nailing cement walls

Five Taboos of Cement Wall Expansion Nail

1. Taboo in selection: Choosing the wrong model = burying hidden dangers.

1. The diameter does not match the wall.

Fatal error: Using < ＜6mm expansion nail in C20 concrete wall (bearing capacity decreased by 70%)

Correct scheme: select according to the wall hardness (8mm for C30 concrete and 10mm for C15 concrete).

2. Misunderstanding of material selection

Ordinary iron expansion nails are used in outdoor humid environment.

Alternative: 304 stainless steel expansion nail/galvanized alloy nail

Second, the installation taboo:

1. Drilling three minefields

Hole depth < expansion tube length

Aperture > expansion pipe diameter 1mm (need to be repaired with glue)

Dust remained in the hole (resulting in insufficient expansion)

2. Consequences of violent installation

Tap the screw directly with a hammer.

Correct operation: screw in 3/4 length by hand, and then tighten it with wrench.

Third, overload taboo: expansion nails are prohibited in these scenarios.

Vibration equipment: air conditioner outdoor unit and ceiling fan (chemical anchor bolt is recommended).

Heavy component: suspension with weight > ＞50kg (structural embedded parts are required).

Hollow brick wall: the falling rate of direct nailing is more than 80% (grouting reinforcement is needed).

Four, environmental taboos: these days don't construction.

Air temperature < 5℃: abnormal solidification of epoxy resin adhesive (tensile strength decreased by 40%)

Humidity > 85%: dew condensation on the surface of metal expansion nail (24-hour rust probability is 30%)

Solution: Use anti-freezing expansion rubber plug/electrothermal drying hole.

V. Maintenance Taboo: Installation ≠ End

Annual inspection: test with a torque wrench, and replace it immediately if it is loose > 15.

Rust treatment: the area with surface rust spots > 30% must be replaced as a whole.

Remedial scheme: the loose expansion nail hole needs to be injected with epoxy resin glue+enlarged hole diameter.

Frequently asked questions

Q: Can the expansion nail be reused?

A: forbidden! After disassembly, the casing is deformed and needs to be replaced with a new nail.

Q: what should I do if I meet the steel bar when punching?

A: Relocate with an offset of ≥5cm. It is forbidden to cut off the main reinforcement.

Keeping these taboos in mind can reduce installation accidents!