Double Expansion Bolts

    It is made of a die-casting zinc alloy material with the characteristics of rust prevention, corrosion resistance and environmental protection, and the product is durable. It has two tapered conical expansion nuts, one threaded and the other unthreaded. One or two spring strips wind the two parts together with two zinc alloy shields and allow the anchor to expand after installation.

所有锚件安装应使用的螺栓长度等于被紧固材料的厚度加上锚件的嵌入深度。双膨胀锚适用于基材较软或强度不够坚固的安装项目中。双头膨胀锚的一端有一个螺纹螺母。安装时，用未螺纹的螺母夹住另一端或另一端，然后先将螺纹螺母端插入孔中。放置孔洞时，要把未有螺母的一端朝上，确保得到充分的膨胀。用锤子轻轻敲打，直到锚与基材表面齐平。取被紧固的夹具，将夹具上的孔与基材上的双孔对齐。 顺时针转动螺栓，直到锚完全固定。不要过度扭转螺栓，因为这可能导致双膨胀锚在孔中旋转并失去其固定强度。

     The length of bolts used for the installation of all anchors is equal to the thickness of the material to be fastened plus the embedded depth of the anchor. Zinc alloy double expansion bolts anchors are suitable for installation projects with soft base materials or insufficient strength. The double expansion anchor has a threaded nut at one end. During installation, clamp the other end or the other end with unthreaded nut, and then insert the threaded nut end into the hole. Place the hole with the end of the nut facing upward to ensure adequate expansion. Hit gently with a hammer until the anchor is flush with the surface of the substrate. Take the clamped fixture and align the holes on the fixture with the double holes on the substrate. Turn the bolt clockwise until the anchor is fully seated. Do not over torque the bolt as this may cause the double expansion anchor to rotate in the hole and lose its fixing strength.

这些膨胀从两侧充分接触和安全持有。安装时，用锤子敲入一个钻孔，然后定位夹具。然后，插入螺钉或螺杆并拧紧。为了达到最大膨胀，在拧入螺钉之前，锚应稍微突出表面。抗拔强度和抗剪强度值为极限值的25% 。双膨胀锚的一个独特之处在于，它们可以很容易地从安装孔中取出并重新使用。要取下一个，只需取出机器螺丝，它就会恢复到原来的形状。然后可以从孔中取出。

    These swells are fully contacted from both sides and held safely. To install, tap in a hole with a hammer and position the fixture. Then insert the screw or screw and tighten. To achieve maximum expansion, the anchor should protrude slightly from the surface before screwing in the screw. The tensile strength and shear strength are 25-30% of the limit value. A unique feature of the double expansion anchors is that they can be easily removed from the mounting holes and reused. To remove one, just take out the machine screw and it will return to its original shape. It can then be removed from the hole.

To install the concrete double expansion anchors, perform the following steps:

1. 在基层上钻一个与锚体相同直径的孔。钻孔深度需要略长于锚体的深度。

1. Drill a hole with the same diameter as the anchor body on the base course. The drilling depth needs to be slightly longer than the depth of the anchor body.

2. 清除孔中的碎屑和杂质后，将双膨胀锚插入孔中，螺纹端部分靠近洞底部。

2. After removing the debris and impurities from the hole, insert the double expansion anchor into the hole with the threaded end near the bottom of the hole.

3. 在将被锚定的安装物体上钻一个孔，将孔对齐，并使用匹配的机用螺钉拧入锚体中的内螺纹。刚开始可以用手旋转拧入螺栓

3. Drill a hole in the installation object to be anchored, align the hole, and screw the matching machine screw into the internal thread in the anchor body. At first, the screw in bolts can be rotated by hand

3. 接着用螺丝刀拧紧机器螺丝，直到它紧靠与安装相连的物体表面。

3. Then use a screwdriver to tighten the machine screw until it is close to the surface of the object connected with the installation.

**The zamac single expansion anchors are  available.