OEM/ODM Supplier Rock Bolt Design Example - ROUNDBAR BOLT – TRM

TRM devoted oneself to manufacturering safety and qualified ground support products for the application in mine, tunnel and slope etc. Beside of Split Set system with friction bolt and paltes, we also provide steel bar bolts like roundbar bolt. Roundbar is a very popluar steel material in the market and steel mill can supply a lot of different standard grade roundbar to meet the different requirements according to the conditions of strata, normally the grade of bolt bar we supply is Q235, Q345, 40Cr, 20MnSi, #45 etc. which is equal to ASTM A36, A6, 5140 AISI A706M ASTM1045 etc. We also could supply other grade of steel meanwhile to help our customer to select a correct grade of steel bar for their roundbar bolt, give customer the best solution to solve their supporting problem with low cost. Screw will be machined at one end of the roundbar bolt and a nut will be screwed on with a pin fixing on the bolt, at the same time we also supply all the nuts and washers used together with the roundbar bolts. We welcome customer to offer us their own design of nuts and washers, and we can supply nuts and washer made by casting, forging and machining. To help mixing the resin capsules and make the roundbar bolt has Anti-Shear resistance in support performance, we also press some “D” shape form along the roundbar bolt body which we called it as “D-Bolt”, it has a much more better performance in the support projects. We also can supply roundbar bolt with forged head which is more convenient to use in the ground support applications.

ROUNDBAR BOLT FEATURES

Different grade of roundbar are available.
Forged head with threadend or shell is available.
a simple, inexpensive ground support system.
Accessories such as washers and nuts are available.
Resin cartridge is available.

INSTALLATION INSTRUCTIONS    

1. A hole with appropriate diameter for size of bar will be drilled into the roof of strata approximately 25mm longer than the roundbar bolt. Measure from where the plate touches the roof to the top of the bolt.

2. Insert resin cartridge into hole. Length and type of resin as specified in the roof control plan.

3. With the bolt in the bolt wrench, insert the torque/tension bolt into the hole to a point where the roof plate is just slightly off the roof line and no excessive boom pressure is applied. Now rapidly rotate the bolt counter-clockwise for 5-10 seconds (or as per resin manufacturers recommendations for type of resin being used) to insure proper mixing of the resin. Always keep hands away from rotating parts.

4. Now hold the bolt assembly in place (do not apply any up-thrust) for a minimum of 10-30 seconds (depending what resin is used) to allow the resin to set up properly.

5. After the resin has set up properly, rotate the bolt assembly clockwise with minimum up thrust and apply a torque to the bolt as per the mine roof control plan. this completes the installation.