How do I remove this bolt? Is a tool needed?

Special tooling is required; otherwise, it’s impossible to do it.

Can the poster provide a detailed structural diagram? Thank you! !

What device is this on? I’ve never seen it before

Haven’t seen it; what kind of device’s bolts are these?

It should be something like a tensioning sleeve; remove the small bolts and then try prying it off from the top of the seal in the middle of the cylinder

This is a labor-saving design for bolts; in the future, disassembly and assembly will require only tightening or loosening these small bolts. Some manufacturers have also come to our company to promote this idea

This post was last edited by zhxf2002 on 2017-7-27 at 21:47. When installing or removing super bolts, it is necessary to follow a triangular pattern. During installation, pull all the smaller bolts back into the plane, tighten the larger bolts to the bottom, then move them back 45° before starting to tighten them in groups of three. The tightening is carried out in two stages regarding torque levels. For example, if the target torque is 50 Nm, then in the first stage all bolts are tightened to 25 Nm. Once all bolts have been tightened to 25 Nm, the torque wrench is adjusted to 50 Nm to proceed with the next stage of tightening. If the number of large bolts happens to be a multiple of 3, then they should also be tightened in a triangular sequence. When removing it, simply follow the order of an equilateral triangle – there’s no need to apply torque in two rounds. For practical use, two torque wrenches are the best option; no special tools are required. Improper handling of this bolt may cause damage, so it is essential to follow the procedure.

This bolt is also known as a multi-stage thrust coupling fastener; it consists of a cylindrical double-ended bolt, an anti-loosening self-locking nut, super gaskets, multi-stage thrust sleeves, and multi-stage thrust bolts. The super gasket is fitted over the stud or bolt, while the locknut is screwed onto the stud or bolt via its screw hole ； Cylindrical double-headed bolt, with a cylindrical middle section and threaded ends. One end of the thread is equipped with a super gasket and an anti-loosening self-locking nut respectively; the super gasket is placed on the inner side, while the anti-loosening self-locking nut is placed on the outer side. On its cylindrical surface, multiple blind holes are drilled at equal angles along the radial direction; a special 1.5° conical surface structure is formed at its bottom. On the threaded end of the other end of the cylindrical double-headed bolt, a super gasket and a multi-stage thrust sleeve are installed – the super gasket is placed on the inner side while the multi-stage thrust sleeve is on the outer side. Multi-stage thrust bolts are mounted on this sleeve, with one end of each such bolt in contact with the super gasket.

http://v.youku.com/v_show/id_XODgyNjI2ODk2.html?firsttime=202; here is a video explaining the principle of super bolts. Very delicate!

With a hydraulic puller, the bolt and hole are in an interference fit, so it’s impossible to remove them by force