Hot-Dip Galvanized P-Type Parallel Clevis
The P-type parallel clevis is a load-bearing link fitting used in overhead transmission and distribution-line hardware assemblies. It consists of two parallel steel plates connected by two transverse bolts or clevis pins. Each connection is secured using a hex nut and cotter pin or another approved retaining arrangement.
The double-plate structure provides a clevis opening at both ends, allowing compatible single-plate or tongue-type fittings to be installed between the parallel plates. The fitting is commonly used to extend the connection length of an insulator string or connect components that must remain in the same connection plane.
P-type parallel clevises may be installed between tower-side fittings, insulator-string hardware, suspension fittings, strain fittings, shackles, link plates and other compatible mechanical components. The exact installation position must follow the approved hardware-string drawing.
Important: The P-type parallel clevis generally changes or extends the assembly length but does not provide a 90-degree change in connection direction. A Z-type right-angle clevis should be selected when the connection plane must be rotated.
Key Features
- Two parallel load-bearing steel plates
- Clevis opening provided at both connection ends
- Two bolted or pinned mechanical connections
- Nuts and cotter pins prevent unintended bolt withdrawal
- Maintains the connection within the same principal plane
- Available in multiple lengths, openings and load classes
- Hot-dip galvanized for outdoor corrosion protection
- Suitable for suspension, strain and tower-side hardware assemblies
- Custom dimensions and permanent markings available according to approved drawings
Typical Technical Specifications
| Product Type | P-Type Parallel Clevis / Double-Plate Link Fitting |
|---|---|
| Structure | Two parallel plates with two transverse connection bolts |
| Plate Material | Carbon steel according to the approved drawing |
| Bolt and Nut Material | Carbon steel |
| Retaining Component | Cotter pin / split pin |
| Manufacturing Process | Plate cutting, punching, drilling and forming |
| Surface Finish | Hot-dip galvanized |
| Connection Direction | Parallel / same-plane connection |
| Representative Load Classes | 70, 100, 120, 160, 210, 250 and 300 kN |
| Application | Insulator strings, suspension sets, strain sets and tower-side hardware |
| Reference Standards | DL/T 759-2023 and GB/T 2314-2008 |
| Customization | Length, plate thickness, clevis opening, bolt diameter, load class, marking and packaging |
Representative Model Selection
| Stable-Design Model | Common Model | Plate Width A | Plate Thickness B | Clevis Opening C | Bolt Diameter M | Connection Length H | Nominal Failure Load |
|---|---|---|---|---|---|---|---|
| P-0770 | P-7 | 40 mm | 6 mm | 20 mm | 16 mm | 70 mm | 70 kN |
| P-1080 | P-10 | 45 mm | 8 mm | 20 mm | 18 mm | 80 mm | 100 kN |
| P-1290 | P-12 | 50 mm | 10 mm | 20 mm | 22 mm | 90 mm | 120 kN |
| P-16100 | P-16 | 60 mm | 8 mm | 22 mm | 24 mm | 100 mm | 160 kN |
| P-21100 | P-21 Series | 60 mm | 10 mm | 24 mm | 24 mm | 100 mm | 210 kN |
| P-25120 | P-25 Series | 70 mm | 12 mm | 28 mm | 27 mm | 120 mm | 250 kN |
| P-32120 | P-32 Series | 80 mm | 14 mm | 32 mm | 30 mm | 120 mm | 320 kN |
The values above are representative selection data. Final dimensions, tolerances, material, bolt configuration and nominal failure load must be confirmed using Jiujin Power’s approved drawing and corresponding mechanical test report.
Connection Function
The P-type parallel clevis provides a double-plate connection at both ends. A compatible tongue, eye plate or single-plate fitting is positioned between the two parallel plates and secured by a transverse bolt.
The fitting can increase the distance between connected components while retaining the same connection orientation. It may also provide limited articulation around the bolt axes when permitted by the complete assembly design.
The fitting must not be used to correct a major dimensional mismatch or force incompatible hardware into alignment.
Typical Applications
- Suspension insulator-string assemblies
- Strain and dead-end insulator-string assemblies
- Tower-side connection hardware
- Connections between shackles and link fittings
- Connections between single-plate and double-plate fittings
- ADSS and OPGW hardware assemblies when specified
- Overhead ground-wire hardware sets
- Substation and busbar support assemblies
Materials and Construction
The two main plates are commonly manufactured from medium-thickness carbon-steel plate using cutting, punching, drilling and forming processes. Critical plate dimensions include thickness, width, hole diameter, edge distance and spacing between the parallel plates.
The connection bolts and nuts are selected according to the specified mechanical load and approved drawing. The end of each bolt normally includes a transverse hole for a cotter pin or another positive retaining component.
Material grades and fastener property classes must be confirmed for the exact model. Similar-looking products may have significantly different mechanical performance.
Hot-Dip Galvanized Surface
The steel plates, bolts and nuts are normally hot-dip galvanized to protect them against atmospheric corrosion during outdoor service. Galvanizing should be completed after the principal forming and machining operations unless otherwise specified.
The required coating thickness, coating mass, adhesion and inspection method must be stated in the purchase specification. Coastal, tropical, industrial and highly polluted environments may require increased coating thickness or additional corrosion-control measures.
Minor differences in surface brightness or zinc crystallization do not alone determine coating quality. Coating performance must be evaluated using the agreed inspection method.
Model Selection
The following parameters should be confirmed before selecting a P-type parallel clevis:
- Required nominal mechanical load
- Center-to-center connection length
- Clevis opening at both ends
- Plate width and thickness
- Bolt or pin diameter
- Thickness of each adjacent tongue fitting
- Required articulation around the bolts
- Material and hot-dip galvanized coating requirement
- Complete hardware-string drawing
- Applicable utility or project standard
The mechanical rating of the P-type clevis should be coordinated with all adjacent fittings. The complete string should not contain an unintended weak link.
Installation Guidance
- Verify the model and dimensions against the approved hardware-string drawing.
- Inspect both plates for cracks, deformation, sharp edges or severe coating damage.
- Confirm that the supplied bolts, nuts and cotter pins match the fitting model.
- Position the adjacent fitting centrally between the two parallel plates.
- Align the connection holes without hammering or enlarging them.
- Insert the specified bolt through both plates and the connected component.
- Install and secure the nut according to the approved assembly requirement.
- Insert the cotter pin fully through the bolt hole and lock it using the specified method.
- Repeat the procedure at the opposite end of the fitting.
- Check that the assembly can articulate as designed without abnormal interference.
Do not replace the specified bolt with an ordinary commercial bolt of unknown material, diameter or mechanical property class.
Quality Inspection
- Raw-material and material-certificate verification
- Plate thickness, width and length inspection
- Clevis-opening and hole-diameter inspection
- Bolt, nut and cotter-pin assembly inspection
- Thread-fit and retaining-hole inspection
- Visual inspection for cracks, burrs, laps and deformation
- Hot-dip galvanized coating appearance and thickness inspection
- Mechanical failure-load testing when specified
- Permanent marking and traceability inspection
- Packaging and quantity inspection
Reference Standards
- DL/T 759-2023 – Link fittings
- GB/T 2314-2008 – General technical requirements for electric power fittings
- IEC 61284 – Overhead-line fittings — Requirements and tests, when applicable
- ISO 1461:2022 – Hot-dip galvanized coatings on fabricated iron and steel articles
- Applicable utility specifications and approved project drawings
Reference to a standard does not constitute certification. Compliance claims must be supported by drawings, inspection records and test reports covering the exact model supplied.
Ordering Information
Please provide the following information when requesting a quotation:
- Required P-type model
- Nominal mechanical load
- Connection length
- Clevis opening at both ends
- Plate thickness and width
- Bolt diameter and fastener property class
- Adjacent fitting models or complete assembly drawing
- Steel material grade
- Hot-dip galvanized coating requirement
- Applicable standard and required test documents
- Quantity, marking and packaging requirements
Frequently Asked Questions
What is a P-type parallel clevis used for?
It connects compatible tongue and plate fittings while extending the length of an overhead-line hardware assembly and maintaining the same principal connection plane.
Does the product contain four bolts?
No. A standard P-type parallel clevis normally contains two transverse connection bolts. In an angled photograph, the bolt head and nut at each side may appear as separate bolts.
Can a P-type clevis change the connection direction by 90 degrees?
No. A Z-type right-angle clevis or another direction-changing fitting should be selected when the connection plane must be rotated.
Are P, PS and PD fittings interchangeable?
No. Their plate arrangements, openings, lengths, bolt dimensions and connection interfaces may differ. The exact model must be selected from the approved assembly drawing.
Can an ordinary bolt replace the original connection bolt?
No. Replacement bolts must have the correct diameter, length, thread, retaining hole, material and mechanical property class required by the approved design.
Can custom connection lengths be supplied?
Custom production is possible according to an approved drawing. Plate dimensions, bolt specifications, nominal mechanical load and galvanizing requirements must be agreed before production.
