Elbow for Backfill Pipeline
Key Specifications at a Glance
| Parameter | Specification |
| Product Name | Elbow for Backfill Pipeline |
| Type | Heavy-duty long-radius backfill elbow (90° standard; 45° / 60° on request) |
| Standard Sizes | DN100 – DN300 (4" – 12") |
| Maximum Working Pressure | Up to 25 bar / 2.5 MPa / 363 psi (PN25); higher on request |
| Burst Pressure | ≥ 4× working pressure |
| Body Material | QT450-10 ductile iron (ASTM A536 Grade 65-45-12 equivalent) |
| Optional Wear Lining | Cr26 high-chrome white iron (HRC ≥ 58) / polyurethane (PU) / HDPE liner |
| End Connection | Grooved (compatible with GOLDDRILL backfill couplings) |
| Surface Treatment | Standard: epoxy powder coating; optional: hot-dip galvanizing, 3PE, FBE |
| Bend Radius | Standard R = 1.5D (long radius); R = 3D / 5D on request |
| Operating Temperature | -40 °C to +80 °C (limited by elastomer / lining selection) |
| Compatible Standards | GB/T 17241.6, AWWA C606, ISO 2531, ASME B16.9, ASTM A536, GB/T 31940 |
| Certifications | ISO 9001, MA / KA (mining safety approval) |
Key Features & Advantages
-
Heavy-duty QT450-10 ductile iron body — tensile ≥ 450 MPa, impact-tough, corrosion-resistant
-
Optional wear lining: Cr26 high-chrome iron (HRC ≥ 58) / PU / HDPE, tailored to the medium
-
Standard PN25 working pressure (2.5 MPa / 25 bar / 363 psi); higher on request
-
Long-radius bend (R = 1.5D) reduces turbulence and concentrates wear at a known, replaceable location
-
Grooved quick-connect interface — 3–5 minute joint, no hot work, repeatable dismantling
-
Epoxy powder coating standard; FBE / 3PE / galvanizing optional
-
Direct compatibility with the GOLDDRILL Backfill Special Coupling (PN25) and HDPE PE100 backfill pipe
-
ISO 9001 quality system and MA / KA mining safety approvals on request
-
Comprehensive documentation: material certificate, dimensional report, hydrostatic test record
Operating Limits & Notes
The Elbow for Backfill Pipeline is designed for the duty described above. For application outside this envelope, please consult GOLDDRILL — typical limits are:
| Maximum particle size | ≤ 25 mm (larger on request) |
| Maximum slurry velocity | ≤ 4 m/s (above this, switch to R = 5D long-radius design) |
| pH range | pH 5 – 11 (wider range with PU or HDPE lining) |
| Maximum chloride content | ≤ 5 000 mg/L (standard) |
| Maximum ambient temperature | -40 °C to +60 °C |
| Service life under design duty | ≥ 18 months continuous duty before scheduled lining inspection |
Quality Control & Documentation
Each elbow is produced under a documented ISO 9001 quality system covering chemical composition, mechanical properties, dimensional inspection and hydrostatic testing. The following documents accompany every shipment:
● Material certificate (chemical composition & mechanical properties)
● Dimensional inspection report
● Hydrostatic test certificate (1.5× working pressure for 30 min)
● Coating thickness and adhesion test report
● MA / KA certificate (where applicable)
● Third-party inspection report (SGS, BV, TÜV, CCIC) on request
Installation & Maintenance
Installation is performed by pairing the elbow with the GOLDDRILL Backfill Special Coupling on either end. Standard procedure:
● Inspect grooved ends for damage, ovality or scoring — replace if any defect is found
● Seat the gasket correctly; verify the elastomer is compatible with the medium
● Mount the coupling housings evenly around the joint, hand-tighten all bolts first
● Tighten bolts in a star pattern to the recommended torque (see coupling datasheet)
● Pressure-test the line at 1.5× working pressure for 30 min before commissioning
Maintenance: visual inspection every 3 months in continuous service; lining thickness check every 6 months at the most heavily worn point (typically 1–2 D downstream of the elbow exit). A spare elbow is recommended for every 10 elbows in service to minimize downtime during lining replacement.
Ordering Information
To order, please provide: diameter (DN), bend angle (90° / 45° / 60°), bend radius (1.5D / 3D / 5D), working pressure class, lining material (Cr26 / PU / HDPE / none), end connection (grooved / flanged / butt-weld), medium description, target service life, and any special coating requirements. Our engineering team will issue a free selection proposal within 3–5 working days.
