Question 1

What is a five-section water-stop tie rod?

Accepted Answer

It consists of two reusable outer threaded bars, two plastic cones and one embedded middle bar with a welded water-stop plate. After stripping, the two outer bars are unscrewed and reused on the next pour; only the middle section stays inside the wall. This keeps consumable cost low while producing a watertight wall penetration.

Question 2

What is the load difference between D15 and D20 tie rods?

Accepted Answer

D15 and D20 refer to the nominal bar diameter (about 15 mm and 20 mm). At the same steel grade, tensile capacity scales with cross-sectional area, so a D20 bar carries roughly 1.7 to 1.8 times the load of a D15. D15 is typical for residential slabs and light walls; D20 is used for thicker walls, higher pour rates and heavier hydrostatic loads. Final selection must always be checked against the formwork pressure calculation for the specific pour height and rate.

Question 3

Which steel grade and surface treatment should I choose?

Accepted Answer

Formwork tie rods are commonly produced from medium and high carbon steel in 8.8 and 10.9 property classes. For corrosion protection: hot-dip galvanizing gives the thickest coating and suits outdoor and marine exposure; Dacromet (zinc-flake) coating avoids hydrogen embrittlement and is preferred for high-strength grades; electro-galvanized is an economical option for general use; black oiled bar is used indoors or where the rod is recovered and reused quickly.

Question 4

Can you produce to our drawing or sample?

Accepted Answer

Yes. We manufacture to customer drawings or physical samples, including non-standard diameters, lengths, thread pitches and plate dimensions. Send the drawing with material grade, tolerance and surface treatment requirements.

Question 5

Which payment terms and Incoterms do you accept?

Accepted Answer

Payment: T/T, and L/C at sight for large orders. Trade terms: FOB Tianjin, CIF, CFR and EXW.

Thread	D15 / D20
Material	Cast iron
Surface	Black / zinc plated

Grade	Notes
Q235	Plain carbon steel. Economic option for light and medium formwork loads. Not heat treated.
45#	Medium carbon steel. The standard formwork tie rod grade in China; quenchable to class 8.8.
40Cr	Alloy steel. Higher hardenability and better fatigue performance than 45#; used where repeated reuse matters.
Class 10.9 bolt	Quenched and tempered alloy steel bolt used in the climbing cone set. Not electroplated without a documented baking cycle.
QT450-10	Ductile (nodular) iron with 450 MPa tensile and 10% elongation. Used for sleeves and embedded plates where toughness and castability matter.
HRB400	Hot-rolled ribbed bar (threaded steel) to Chinese standard. Used for embedded foot bolts; good bond with concrete.

Cast Iron Water Stop Nut

Specifications

Technical Specifications

Production Process

Material Grades Explained

Applications

Procurement Guide

Procurement Information

Backed by an ISO-certified factory

Cast Iron Water Stop Nut — Answers for Engineers and Buyers

Cast Iron Water Stop Nut

Cast Iron Water Stop Nut

Specifications

Technical Specifications

Production Process

Material Grades Explained

Applications

Procurement Guide

Procurement Information

Backed by an ISO-certified factory

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Cast Iron Water Stop Nut — Answers for Engineers and Buyers