Transformer Spade Terminals, Transformer Spade Connectors / Material and connection variants
Bronze Stud Connectors for Transformers
Bronze stud connectors for transformers join a compatible transformer stud to a NEMA-spaced terminal palm using a split-clamp arrangement. Cable Glands India offers natural and tin-plated configurations for pad-mounted transformers. The representative design has a threaded stud bore, two clamp fasteners and a straight two-hole palm, with final geometry controlled by the approved drawing.
Price on request. Quotation depends on the approved alloy, geometry, finish and order quantity.
Product overview
Split-Clamp Transformer Stud Connection
The representative connector uses a split around the threaded stud interface and clamp hardware to secure the assembly. The bore, split geometry, fasteners and palm form one engineered connection. Confirm the stud diameter, thread pitch and required engagement before selection. The clamp must not be treated as a universal adapter for unrelated studs. Installation torque and tightening sequence should come from the approved assembly instructions, because they depend on both the hardware and connector body.
Two-Hole NEMA-Spaced Palm
The flat palm provides the bolted interface for a compatible lug or busbar pad. Its holes follow the specified NEMA-spaced arrangement. The two holes belong to one electrically connected terminal, not separate poles. Palm thickness, edge distance and contact area must accommodate the complete joint stack. The attached cable needs support to prevent its weight and bend forces loading the bushing. Check tool clearance around both palm bolts and clamp fasteners within the transformer compartment.
Body Alloy and Clamp Hardware
The term bronze stud connector does not, by itself, identify a specific alloy. State the approved body grade and the material, dimensions and finish of the clamp hardware. Do not assume that a bolt visible in the representative illustration is included or rated for a particular torque without an agreed bill of materials. Natural and tin-plated body finishes can be specified. The complete assembly must be assessed for mating-material compatibility and the intended service environment.
Key features
- Bronze / copper-base alloy to approved drawing material specification for traceable procurement.
- NEMA-spaced palm for compatible bolted terminal layouts.
- Natural and tin-plated finish options.
- Straight connection geometry for the specified transformer arrangement.
- Machined contact surfaces, bores and threads to an approved drawing.
- Configuration review for electrical OEMs, EPC contractors, power utilities and distributors.
NEMA palm and bolted contact interface
The palm provides the contact area between the transformer connector and the mating lug or busbar. Hole spacing supports interchangeability only when hole diameter, edge distance, palm thickness and terminal orientation also agree. Confirm access for sockets and spanners in the enclosure. A greater number of holes does not automatically permit a higher current or a larger number of independent outgoing circuits. The assembled connection and conductor arrangement govern the operating duty.
Natural metal and tin-plated contact surfaces
Natural finish retains the appearance of the selected base material. Tin plating provides a different surface condition for the specified joint design and handling environment. Specify preparation, coating thickness and coverage before manufacture. Threads may require allowance or masking to preserve fit after plating. Evaluate the complete joint when connecting dissimilar metals, including the conductor, lug, fasteners and environmental exposure. Do not assume that tin plating alone establishes aluminum-conductor compatibility.
Stud fit and dimensional control
The stud connection must match both the nominal size and the detailed thread designation. Pitch, class of fit, usable thread depth and entry chamfer affect assembly. Check shoulder contact and available engagement against the bushing drawing. Incorrect thread combinations can appear to start and still damage the mating terminal. Use the OEM installation procedure and specified tightening torque; neither the alloy name nor a catalog illustration defines a safe torque setting.
Technical specifications
| Parameter | Specification / ordering requirement |
|---|---|
| Brand | Cable Glands India |
| Product category | Transformer Spade Terminals, Transformer Spade Connectors |
| Material | Bronze / copper-base alloy to approved drawing |
| Manufacturing form | Split-clamp stud connector with bolted terminal palm |
| Finish | Natural or tin plated, as specified |
| Application | Pad-mounted transformer terminal connections |
| Mounting pattern | NEMA spaced; exact dimensions to approved drawing |
| Hole configurations | Representative two-hole palm; other approved layouts by drawing |
| Stud interface | 3/8, 1/2, 3/4 or 1 inch nominal options; confirm pitch and engagement |
| Thread series | UNC, UNF, UNEF or UNS as specified; ASME B1.1 drawing requirements |
| Dimensions and tolerances | Palm length, width, thickness, bore and hole position to drawing |
| Electrical rating | Design-specific; requires assembly validation |
| Supply documentation | Material and dimensional records as agreed at quotation |
Material composition and international designations
| Constituent / requirement | Grade information |
|---|---|
| Connector body alloy | Specify the approved bronze grade |
| Clamp hardware | Material and finish to assembly drawing |
| Stud bore | Diameter, thread and engagement to mating stud |
Composition values are weight percentages where shown. The governing purchase specification and material certificate determine acceptance, including any residual-element limits not reproduced here.
| Reference | Procurement interpretation |
|---|---|
| Specified material | Bronze / copper-base alloy to approved drawing |
| International designation / equivalent | Bronze stud connector is a product description, not an alloy designation. International material comparison requires the specified body grade and a separate specification for clamp hardware. |
| Substitution rule | Compare the full material specification and product form; obtain approval before substituting. |
Product variants
| Variant | Configuration |
|---|---|
| Natural finish | Bronze / copper-base alloy to approved drawing with specified machined contact surfaces |
| Tin-plated finish | Same base material with ordered tin coating and thread treatment |
| Palm configuration | Two-hole representative split-clamp stud connector; alternate approved patterns on inquiry |
| Threaded connection | Diameter, thread series, pitch and engagement length selected from the drawing |
| OEM version | Customer drawing, revision control, marking and inspection requirements |
Industrial applications
Bronze Stud Connectors for Transformers are intended for the terminal connection zone of pad-mounted transformers. They can form part of an OEM bushing-to-lug or stud-to-palm assembly, subject to the transformer design. Utilities use approved connector configurations for equipment replacement and maintenance programs. EPC contractors specify the terminal interface alongside cables, lugs, busbars and installation hardware. Distributors should identify the actual material and thread arrangement so that a visually similar part is not supplied as an unapproved replacement.
For retrofit work, check the existing terminal drawing, enclosure clearance and conductor approach before ordering. Confirm corrosion exposure, operating temperature and fault duty with the equipment owner. Installation and maintenance should follow the applicable equipment instructions with the system isolated and made safe.
Manufacturing process
- Review the stud interface, bronze body grade and clamp assembly drawing.
- Produce the body blank using the specified material and process.
- Machine the stud bore, thread, clamp split and fastener features.
- Machine the straight palm and specified NEMA-spaced bolt holes.
- Apply the required finish and assemble the approved clamp hardware where included.
- Check fit, critical dimensions and identification against the inspection plan.
Production release should connect the drawing revision to the material lot, machining setup and inspection plan. Changes to palm thickness, bore geometry or hole layout can affect both mechanical fit and the thermal performance of the assembled joint. Agree first-article checks for a new design before repeat quantities are released. Pack contact surfaces to limit damage during transport and keep natural and plated batches clearly identified.
Quality standards and documentation
| Control area | Requirement to agree |
|---|---|
| Material verification | Specified alloy, product form and lot documentation |
| Dimensional inspection | Palm dimensions, thickness, hole location, bore and stud engagement |
| Unified threads | ASME B1.1 designation and suitable gauging as required by drawing |
| Tin coating | ASTM B545 when specified and applicable, with agreed thickness and acceptance criteria |
| Electrical verification | Temperature-rise, resistance and fault-duty requirements for the complete assembly |
| Certification documents | Request current certificates and their scope for the quoted supply |
NEMA spacing describes the mounting interface; it is not a standalone certification of the finished connector. Standards listed here are specification references to be agreed for the order. No universal UL listing, IEC approval, ISO certification or blanket environmental-compliance claim is implied for every custom variant. If regulated-substance requirements apply, identify the destination market and required declaration before selecting a lead-containing alloy.
Why choose Cable Glands India
This product range brings material selection, connection geometry and finish into one drawing-based inquiry. Buyers can compare bronze, copper, forged brass and cast brass versions within the same transformer terminal family. A clear specification helps procurement teams obtain comparable quotations and helps engineering teams separate material identity from assembly performance. State the required inspection records, marking and packaging at the quotation stage so the supply scope is reviewable before manufacture.
Questions and answers
What is different about a split-clamp stud connector?
Its stud interface includes a clamp split and fasteners as part of the connection design. The bore, thread, clamp geometry and hardware must be matched as an assembly; the connector is not a universal fit.
Are these connectors suitable for pad-mounted transformers?
They are intended for pad-mounted transformer terminal connections where the approved bushing, stud, palm, conductor and enclosure arrangement matches the connector drawing. Confirm electrical duty, clearances and mechanical loading with the transformer OEM before release.
Are the mounting holes NEMA spaced?
Yes. The palm uses a NEMA-spaced mounting arrangement. Specify the exact hole count, center-to-center dimensions, hole diameter and orientation on the order drawing; the phrase NEMA spaced alone is not a complete interface specification.
Can I order natural and tin-plated finishes?
Yes. Both natural metal and tin-plated finishes can be specified. State coating thickness, coverage, masking, contact-surface requirements and inspection criteria. Tin plating does not change the underlying alloy designation.
Which stud threads can be supplied?
The family includes nominal 3/8, 1/2, 3/4 and 1 inch stud interfaces, with UNC, UNF, UNEF or UNS forms where the drawing requires them. Confirm diameter, pitch, class, engagement length and thread direction; not every diameter uses every series as a standard combination.
What is the current rating?
There is no single current rating for all geometries. The assembled connection must be assessed for conductor size, contact area, temperature rise, installation torque and fault duty. Request the test requirements for your approved design instead of selecting by alloy or hole count alone.
Are installation bolts and washers included?
Specify the complete hardware bill of materials in the inquiry. Inclusion, bolt material, coating, washer arrangement and approved tightening torque must be confirmed for the supplied assembly.
Can a similar international alloy be substituted?
Use the specified grade and product form as the procurement baseline. A proposed substitute needs a comparison of chemistry, mechanical properties, conductivity, casting or wrought condition and the governing standard, followed by customer approval.
What information is needed for a quotation?
Send the drawing and revision, alloy, quantity, stud thread, palm dimensions, NEMA hole pattern, finish, inspection documents and delivery destination. Identify prototype quantities separately from repeat production requirements.
Request a technical quotation
Send your drawing and revision for Bronze Stud Connectors for Transformers, together with quantity, finish, stud thread, NEMA palm layout, inspection requirements and delivery destination. Cable Glands India can review the requested configuration for quotation.
Contact us for a quotation or compare transformer spade terminals and connectors.
