Supplying bolt manufacturers reinforced self into the hollow tunnel grouting anchor factory according to the user's technical requirements, a variety of customized and strength hollow bolt. Welcome to the new and old customers to inquire, we will give you the best service and price. The factory production of hollow bolt that good thick-walled seamless material, forming a perfect fast surface craft and workmanship threaded fittings, truly unified bolt grouting, anchoring and other functions. Ordinary hollow grouting anchor by anchor head, hollow threaded bolt body, only the pulp plug, plate, nuts and other components, each of its parts are in order to ensure maximum grouting mortar when filling full, dense and mortar can penetrate into the surrounding rock fissures at up to tens of kilograms of pressure, and can be easily mounted plate and nut. Features: 1. hollow design, the bolt to achieve a grouting tube function, to avoid the loss of mortar grouting pipe when pulled out of traditional construction process caused. 2. full grouting, grouting pressure can achieve, improve project quality. 3. Due to the role of the parts, the center is very good rod, mortar anchor body can be full-length wrap to avoid the risk of corrosion, and achieve long-term support purposes. 4. Easy installation, no on-site processing thread, you can easily install plate and nut. 5. The combination of supporting special injection pump and bolt grouting process, is the only complete solution to the traditional problems of supporting anchor anchorage system. Technical parameters: the factory according to the user's technical requirements, a variety of custom hollow bolt and strength. We offer the following table according to conventional standards: Specifications JT25 JT22 JT32 outside diameter (mm) 25 22 32 tensile strength (KN) ≥150-180 ≥150-180 ≥220-250 grouting aperture (mm) ≥15 ≥15 ≥22 hole diameter (mm) 42 42 51 L standard thread length direction (m) 3 3.5 4 4.5 length error ± 2.5%