JDG (KBG) thin-wall steel conduit items: clamps and couplers (straight-pipe joints) are included in the conduit-laying items and must not be applied separately (DB11/T 2382-2024 Table C.4.91-4)

Topic Positioning

Item application for Beijing DB11/T 2382-2024 Annex C Table C.4.91-4 "snap (clip) type thin-wall steel conduit" (JDG/KBG) laying items: whether clamps (pipe clips/hanger clamps) and couplers (straight-pipe joints) are included in the laying items and need separate application.

Core Conclusions

JDG (KBG) thin-wall conduit laying items already include clamps and straight-pipe couplers (connecting sleeves) — no separate items, else double pricing. Basis: the item's "work content" lists fitting clamps, jointing, fixing, and the "materials" column carries clamps and couplers by content — accessories covered in both process and material must not be relisted.

Per Table C.4.91-4 sub-tables (material contents per meter):

• 4.1 Exposed in brick/concrete (C4-11-119~124): work "positioning, marking, drilling, fitting clamps, sawing, laying, jointing, fixing, installing fittings". C4-11-119 (DN15) includes: JDG(KBG) conduit 1.0300 m, coupler 15 0.1648 pcs, threaded box connector 15 0.4120 pcs, clamp 15 1.4420 pcs, galvanized wood screws 2.9120 pcs, light rivets 2.9400 pcs (fixings included); C4-11-121 (DN25): coupler 25 0.1648 pcs, clamp 25 0.8549 pcs (clamp content falls with diameter).
• 4.2 Concealed in brick/concrete (C4-11-125~130): work "positioning, marking, sawing, laying, jointing short pipes, fixing, installing fittings". C4-11-125 (DN15) includes coupler 15 0.1648 pcs; materials include no clamps — embedded runs need none, so no clamp item arises.
• 4.4 On steel wire rope (C4-11-137~140): work "positioning, marking, fitting clamps, sawing, bending, laying, installing fittings". C4-11-137 (DN15): coupler 15 0.1648 pcs, hanger clamps (JDG/KBG) 15 1.3390 pairs, galvanized bolts M6x(16-25) 1.3520 sets, galvanized washers 6 1.3520 pcs.

Application rule: wherever a laying item's work content includes "fitting clamps/jointing/fixing" and its materials list clamps and couplers, use the in-item contents (which vary with laying method and diameter) — no external supplements; clamps and couplers are not separately itemized or priced.

Applicable Boundaries

• Applies to general installation pricing under Beijing DB11/T 2382-2024; other provincial quota norms, industry quota norms (e.g., railway TB/T series), and contractors' in-house norms must be verified separately.
• Figures here are samples: exposed DN15/DN25, concealed DN15, wire-rope DN15; other sizes and sub-tables (the table also covers steel-structure supports etc.) share the same structure — values per the standard text.
• "No separate item" covers only clamps and couplers included in the laying items; junction-box installation and conduit supports (wire rope, shaped-steel supports themselves) are outside — apply the corresponding items, not this conclusion.
• Final pricing per the contracted current edition; re-verify on any standard revision.

Further Reading

• DB11/T 2382-2024 Annex C, Table C.4.91-4 sub-tables 4.1 (C4-11-119~124), 4.2 (C4-11-125~130), 4.4 (C4-11-137~140) — check each item's work content and materials columns.
• Adjacent items (junction boxes, support fabrication/installation) for the pricing interface.