Stud bolts, heavy hex nuts, through-hardened washers, jackscrews, spectacle blind pivot studs and U-bolts, made in Houston to your drawings and specifications.
An 8-inch (NPS 8) Class 300 pipe spool with five raised-face flange joints, taken apart the way a fitter does it. The U-bolts come off the supports, then the spectacle blind is swung shut: its nuts spin off, eleven studs are drawn back, the jackscrews spread the joint and the figure-8 turns on the one stud left in. After that each joint is unbolted in turn: the nuts spin off, the flanges pull apart, and the twelve studs and the spiral-wound gasket are left in the gap. The bolting we make is in colour. Press Solid view for a steel model, or Cutaway to see the gaskets seated between the raised faces, the pipe and fitting walls, and the studs running through the flanges.
Full-length threaded studs, twelve 7/8 in.-9 UNC × 5-1/2 in. per joint on a 13 in. bolt circle (ASME B16.5 Class 300, NPS 8, raised face). Tightened in passes in a cross pattern, their stretch is the clamp that keeps the gasket seated.
Two per stud, 1-7/16 in. across the flats and 55/64 in. thick (ASME B18.2.2). Wider and thicker than a standard nut, for more bearing area and thread strength. Turning the nut stretches the stud.
One under each nut, the practice ASME PCC-1 Appendix M covers: a smooth, hard face for the nut to turn on, so torque gives a more consistent stud load. Shown to ASTM F436, 1-3/4 in. outside diameter.
Two screws 180° apart, tapped through one flange, that push the joint open evenly so the blind can be turned or a gasket changed.
The stud through the 1 in. hole in the blind's web. It stays in while the other eleven come out, and the figure-8 swings round it from open to closed. Longer than the rest, 6-1/2 in., to take the blank and a second gasket.
Hold the line on its supports: 5/8 in. rod over the 8 in. pipe, legs through the support beam's top flange, with a nut and a lock nut underneath on each leg.
Studs, heavy hex nuts, washers and U-bolts for your piping, to your drawing. Send us your drawings and material spec.
Request a quote832-446-3442A generic 8 in. Class 300 spool, not any maker's design. The flanges, tee, elbow, studs, nuts, washers, gaskets, pipe and spectacle blind follow the standards named below. The jackscrews, the supports and the cast body shapes of the tee and elbow are illustrative, the U-bolt is a typical catalogue size, and the 6-1/2 in. stud length at the blind is calculated. Stud lengths, materials and torque come from your piping spec and your own PCC-1 procedure. We manufacture to your drawings and specifications.
Drawn to ASME B16.5 (flanges, flanged tee and elbow, stud size and length), ASME B16.20 (spiral-wound gaskets), ASME B18.2.2 (heavy hex nuts), ASTM F436 (hardened washers), ASME B16.48 (spectacle blind), ASME B36.10M (pipe) and MSS SP-58 (U-bolts), with assembly practice from ASME PCC-1.
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