Assemblies and kits
Riveted · fitted · kitted
Riveted and welded sheet-metal assemblies, and kits of matching metal and plastic parts, painted to match and packed as one unit.
QuantitiesKits and sub-assemblies in scheduled batches
Capabilities · 04 · Coiled · ground · finished
Custom compression and extension springs to your drawing
Springs produced to your drawing by a specialist spring manufacturer in our network, not taken from a catalog. Each order comes with a material report and an inspection sheet that checks the figures on your drawing.
At a glance
| What we produce | Compression and extension springs, including custom end loops and ground ends. |
|---|---|
| Processes | Coiling · end grinding where specified · stress relief and heat treatment · finishing |
| Materials | Spring steel and stainless steel, grade per drawing. |
| Finishes | Black oxide, passivation and other finishes on request. |
| Tolerances | To your drawing and specification. Tolerances and features that cannot be held are raised before production; any drawing change is approved by you in writing. |
| Quantities | From prototype quantities to production lots. |
| Lead time | Confirmed in the quotation. |
| Documents | Material report and inspection sheet with each order; photos. |
What the spring manufacturer does
Compression springs
Open or closed ends, ground where your drawing calls for it, so the spring stands square under load.
Extension springs
Coiled with initial tension and the end loops on your drawing: machine, crossover or extended loops.
Heat treatment
Stress relief after coiling, so the spring holds its free length and load in service.
Inspection sheet
Load at stated lengths, free length, wire and coil diameters, measured for each lot and recorded on the inspection sheet.
Materials
| Material | Examples of grades | Applications | Suitable finishes | Note |
|---|---|---|---|---|
| Spring steel | Grade per drawing | General compression and extension springs | Black oxide, painting | – |
| Stainless steel | Grade per drawing | Springs exposed to moisture or cleaning | Passivation | Stainless spring wire has a lower working stress than spring steel; the design should allow for it. |
Finishes
| Finish | Materials | What to specify |
|---|---|---|
| Black oxide | Spring steel | Appearance and light corrosion protection. |
| Passivation | Stainless steel | Cleanliness after coiling. |
| Other finishes | On request | Specify with the drawing; this is confirmed before the quotation. |
Tolerances and inspection
Tolerances come from your drawing and specification. Your drawings go to the production engineers of the factory selected for your part. If a tolerance or a feature cannot be held, we raise it before production, and any change to the drawing is confirmed and approved by you in writing. Production is to the drawing.
A spring is specified by what it does, not only by its geometry. Give the load at one or two stated lengths, the free length and the space it must fit, and the manufacturer designs the coil count and wire to meet them.
The inspection sheet supplied with each order reports the figures your drawing specifies, measured for each lot.
Inspection and documents
The factory inspects each order to your drawing or QC sheet and supplies a report. Our team in China then carries out an independent quality verification at the factory, after production and before the goods are released, and the packing is photographed. Where you specify 100% inspection, every part is inspected. Where first articles are required, series production is released only after your written confirmation. Material reports or certificates are supplied where your drawing or PO requires them.
Design notes
Engineering note
Give load at a stated length.
Wire size and coil count alone do not define a spring. Load at a stated length is the figure the inspection sheet checks.
Engineering note
Show the space, not only the spring.
State the bore it works in or the rod it slides over. Diameters change slightly under load.
Engineering note
Specify whether the ends are ground.
Ground ends add cost and ensure the spring stands square; open ends cost less. The drawing governs.
What to send for a quote
- PDF drawing with load at stated lengths, free length and diameters
- Material and finish
- End type: ground, closed or open; loop type for extension springs
- Quantities: prototypes, first lot and expected yearly volume
Send to or@paxis-hk.com. The RFQ checklist explains each item.
Questions
Do you produce springs from a catalog?
No. Springs are produced to your drawing by a specialist spring manufacturer in our network.
Can a spring be designed from the load and installation space?
Please send the known requirements: load, travel, and the space the spring must fit. The manufacturer proposes a design, and you approve the drawing before production.
What comes with the springs?
A material report and an inspection sheet with each order, and photos before and after packing. Springs can also be supplied as part of assemblies and kits.
Is there a minimum order for custom springs?
There is no fixed minimum. Where a very small quantity is uneconomical, this is stated before the quotation.
What must a spring drawing state?
Load at a stated length, free length, wire and coil diameters, material, end type and finish. The inspection sheet reports the figures your drawing specifies.
Related capabilities
Jigs and fixtures
Machined · hardened · assembled
Base plates, locating pins, clamps and nests, and the welding and riveting fixtures that keep repeat batches identical.
QuantitiesSingle fixtures or small sets
CNC machining
Milled · turned · 5-axis
Housings, holders, plates, pins, shafts and rings in aluminum, stainless steel, steel, brass, copper and technical plastics.
QuantitiesFrom about 10 first articles to production lots of thousands
Send your spring drawing
Email the PDF and STEP files with material, finish and quantities to or@paxis-hk.com, or use the short form. Drawing questions are raised before the quotation.