A spring clip is a stamped part whose job is a force: the force it takes to push a contact into it, the force it takes to pull the contact out, the force it puts on a hose or a cable. That force comes from the alloy, the thickness and the shape, and it is designed, not found. The stock catalogue covers the standard rings and hose clamps; the clip for your connector, your shaft or your cable is stamped to a drawing that starts with the force.
EKINSUN LTD is a custom parts manufacturer that makes spring clips, retaining rings, crimp plates and wire clamps to drawing in spring steel and stainless: clips that hold a copper contact in an industrial plug with a set insertion force, rings in DIN 471 / 472 forms and custom shapes, clamps that grip a conductor under a screw, cable and hose clips, from single-stage tooling for a first batch to progressive dies for volume. The type table below lists what is stamped; the force table explains what decides it; the negative-space table marks what is stock, what is stamped and what is machined.
"A clip that holds a 6 mm copper contact in the housing with 15 to 25 N of extraction force, stainless, half a million a year, and a first thousand next month."
The force window comes first; the die that makes it in volume comes second; the first thousand come from a simpler die in between.
| Type | Form | Materials | Stock or made | Where it goes |
|---|---|---|---|---|
| Contact retaining clip | external clip gripping the outside of a copper contact | 301 / 304 stainless, spring steel, phosphor bronze | made to the contact and the force | industrial plugs, connectors, charging sockets |
| External retaining ring, DIN 471 form | circlip with lugs | 65Mn spring steel, 1.4122 stainless | stock 3–300 mm; custom shapes made | shafts — see retaining rings |
| Internal retaining ring, DIN 472 form | circlip for a bore | as above | stock 8–300 mm; custom made | housings |
| E-clip and wire snap ring | radial clip; round-wire ring | spring steel, 304 | stock DIN 6799 / DIN 7993; custom made | small shafts |
| Push-on (starlock) clip | toothed cap that bites a plain shaft | black spring steel | stock M3–M12 | shafts without a groove |
| Crimp plate / wire clamp | stamped plate that holds a conductor under a terminal screw | steel, 304, spring steel | made | terminals, distribution boxes |
| Cable clip, R-type and P-type | wire or strip clip around a cable | spring steel, 304, rubber-lined steel | stock D5–D50 and M14–M200; custom made | cable and pipe runs |
| Saddle and nail-in clips | strip clip with fixing holes | steel, 304, nylon | stock; custom made | cable runs |
| Hose spring clamp, band and Japanese type | spring band around a hose | spring steel, zinc or zinc-flake | stock 6–36 mm | coolant and fuel hoses |
| Spring band clamp, custom | as above, sized to the hose | spring steel | made | OEM hoses |
| Leaf spring and contact spring | flat spring of any shape | spring steel, phosphor bronze, beryllium copper | made | switches, latches, battery contacts |
| Panel and trim clips | clips that snap into a panel hole | spring steel, 304 | made | enclosures, vehicle trim |
| Factor | Effect | How it is set |
|---|---|---|
| Alloy | spring steel gives the most force per thickness; 301 stainless a little less and no rust; phosphor bronze less but conducts and does not fret | chosen from the environment and whether the clip carries current |
| Thickness | force rises steeply with thickness; so does the risk of overstress | chosen with the alloy for the force window |
| Shape | the free opening against the gripped diameter sets the deflection; the arm length sets the stiffness | designed from the contact or shaft and the force window; prototyped on a simple die |
| Heat treatment | spring steel is hardened and tempered after forming; 301 is used in a rolled temper; beryllium copper is age-hardened | specified with the alloy |
| Finish | phosphate and oil, zinc, zinc-flake or plain stainless; plating adds no force but hydrogen embrittlement must be baked out on hardened steel | specified from the environment |
| Cycles | a clip that is mated once can be stressed harder than one mated a thousand times | the cycle count sets the allowed stress |
The practical route is to state the force window and the cycles, let the clip be designed to them, and prove it on a single-stage die with a few hundred pieces before the progressive die is cut. The drawing that comes out of that batch is the one the volume die is built from.
| What you need | In the catalogue? | What we make |
|---|---|---|
| A DIN 471 / 472 circlip, E-clip, starlock washer or hose spring clamp in a stock size | Yes | Buy it from stock; no one-off competes with a catalogue ring or clamp. |
| A cable clip, P-clip or saddle clip in a stock diameter | Yes | Stocked; buy it. |
| A clip that must hold a specific contact with a specific force | No | Designed to the force window, proved on a single-stage die, produced on a progressive die; first batch from a few hundred. |
| A retaining ring of a custom shape — extra lugs, a tab, an asymmetric opening | No | Stamped in spring steel or stainless to drawing. |
| A crimp plate or wire clamp for your terminal block | No | Stamped; thread or hole to your screw. |
| A hose or band clamp sized to an OEM hose | No | Stamped and formed to the hose; force to the pressure. |
| A flat spring or contact spring in phosphor bronze or beryllium copper | No | Stamped and heat-treated; see also terminals and contact pins. |
| A clip in aluminium 6061 or 7075 | No | Not offered: aluminium has no useful spring; we quote 301 stainless or spring steel and say why. |
| Material | Designation | Where it fits here |
|---|---|---|
| Spring steel | 65Mn, C67S, C75S, SK5; hardened and tempered | the highest force per thickness; phosphate, zinc or zinc-flake |
| Stainless spring | 301 / 1.4310, rolled temper | rust-free clips with nearly the force of spring steel |
| Stainless 304 | 1.4301 | clips and clamps with lower force and better formability |
| Stainless 316L | 1.4404 | marine and chemical clamps |
| Phosphor bronze | CuSn6 / CuSn8 | clips that carry current; no fretting |
| Beryllium copper | CuBe2 | high-cycle contact springs |
| Low-carbon steel | DC01 | crimp plates and cable clips that do not spring |
| Aluminium 6061 | AlMg1SiCu | the housing a clip sits in; not a clip material |
| Aluminium 7075 | AlZn5.5MgCu | as above |
By the alloy, the thickness and the shape: the free opening against the gripped diameter sets how far the clip deflects, the arm length sets its stiffness, and the alloy and heat treatment set the stress it can take. The force window and the number of cycles are specified first; the clip is designed to them and proved on a first batch.
Hardened spring steel for the highest force in a small section; 301 stainless where the clip must not rust; phosphor bronze or beryllium copper where the clip carries current or sees very many cycles. Aluminium and plain 304 are not spring materials.
Yes. Rings in DIN 471 / 472 forms and custom shapes are stamped in 1.4122 or 301 stainless as well as spring steel, and wire-cut for a handful of pieces.
A few hundred on a single-stage die, which is also the batch that proves the force before a progressive die is cut. A handful of prototypes are wire-cut and hand-formed without a die.
EKINSUN LTD is a custom parts manufacturer that makes spring clips, retaining rings, crimp plates, wire and hose clamps and flat springs to drawing in spring steel, 301 / 304 / 316L stainless, phosphor bronze and beryllium copper, from single-stage tooling to progressive volume, with a quote within 12 hours.
No list price. The die is quoted separately: a single-stage die for the first batch is modest, the progressive die for volume is an investment recovered over the run. Part price follows alloy, thickness, heat treatment, finish and quantity. The quote shows die and part price for each stage.
Diameter and material of the contact, shaft, hose or cable; insertion and extraction or clamping force; cycles; housing space; environment; quantity now and per year. A sample works. Prototypes from 1 piece without a die, quote within 12 hours.
Spring clips, rings and clamps designed to the force and stamped for each stage of the quantity — quote in 12 hours.