If we order large quantity springs, will you house the springs, wire forms, and ship to us based on a required basis?

Our warehouse provides specific stock service for long term business. You can make your shipment schedule on an annual, monthly basis. We will ship on a specific schedule.

What payment term do we accept for spring orders?

We could accept payment terms based on T/T, L/C at sight, DP, Westunion.

Black Oxide Carbon Steel Crank Arm Spring

Name: Black Oxide Carbon Steel Crank Arm Spring
Brand: Yueqing Dofo Spring Manufacturing Co., Ltd.
SKU: 945419615

Zhejiang, ChinaYueqing Dofo Spring Manufacturing Co., Ltd.

US$0.10-1.00

10,000 Pieces

Product specifications

Type

Sample price:US$80.00/piece.Request sample

Product profile

Customization

Available

Function

Pressed, Buffer

Material

Steel

Model NO.

DF2012178

Usage

Industrial, Auto, Motorcycle, Home Appliance

Load Type

Compression

Production Process

Cold Roll

Shape

Coil

Product Name

Crank Arm Spring

Business Mode

Factory OEM

Material Standard

GB 4357-09 or Equivalent

Wire Range

From Min 0.1mm(0.004inch) to Max 12mm(0.48inch)

Winding Direction

as Per Your Request

End Type

Closed and Ground

Surface Treatment

Black Oxide

Coating Thickness

8~10 Micrometer

Testing Method

Random Sample Inspection

Tolerance

GB Standard, Grade II or as Per Your Requirement

Spring Rate Tolerance

+-3%~10%

Aql Level

Aql 1.0

Packing Method

OPP Bags with Blank Carton

Normal Carton Size

23X23X31/Cm with No Mark

Certificate

ISO9001, SGS, RoHS, CE, Ts16949

Transport Package

Carton and Outer Wooden Case

Specification

customized

Trademark

DOFO

Origin

Wenzhou, China

HS Code

7320909000

Production Capacity

1, 000, 000 Pieces Per Month

Key features

RoHS Compliant Materials: All spring materials including carbon steel and stainless steel meet European RoHS certification standards.

Custom Design Support: Engineers provide CAD, 3D, and 2D design assistance to optimize production costs and meet specific needs.

Flexible Order Quantities: We support both small quantity and large run orders based on customer demand to find the most effective solution.

Sample Charge Refund: Custom spring sample charges are refunded upon receipt of the formal order, excluding additional mold fees.

Fast Lead Time: Delivery within 25 days for standard springs in our mold range; 30-40 days for complex shapes.

Diverse Coating Options: Various coating methods available including Black Oxide, Zinc, Nickel Plated, and Stainless Steel washing.

Wide Material Range: Manufacture springs from wire diameters 0.001 to 0.075 inches using high-grade carbon, stainless, and music wire.

Professional QA/QC: 100% inspection for finished products including visual and function checks by 8 dedicated QA/QC inspectors.

Company profile

High Repeat Buyers ChoiceIn-stock Capacity100% Finished Products InspectionQuality Assurance

Yueqing Dofo Spring Manufacturing Co., Ltd.

Zhejiang, China

CertifiedBusiness Type: Manufacturer/Factory & Trading Company CertifiedR&D Capacity: ODM Service Available CertifiedCustomization Options: Customization from Samples, Customization from Designs, etc. CertifiedExport Year: 26 Years CertifiedNearest Port: Ningbo PortAverage Response Time: ≤1.80h

AI-Powered supplier vetting

SummaryThe supplier presents itself as a professional technical supplier with 3D design, R&D, ODM, and broad customization capabilities. It reports structured production, testing, packing, quality-control, traceability, corrective-action, and complaint-handling procedures, as well as valid contracts with associated subcontractors and inventory capability. Export experience is stated at 26 years, with self-operated import/export rights and 21%–30% of sales from exports. However, it has no overseas warehouse, showroom, agents, or branches, and reports no offline trade-show participation. Certification holdings are explicitly described in the company profile, but current validity is not independently established. Financial credibility cannot be assessed because the supplied financial fields contain zero values. Customer cases and named customer references are not provided.

Supplier typeThe supplier is explicitly identified as a professional technical supplier and describes a mature structure covering management, design, production, testing, and packing. It also has valid manufacturing contracts with associated subcontractors and self-operated import/export rights, supporting classification as a manufacturing-oriented technical supplier.

CertificationsThe company description states that it obtained ISO9001, TS16949, ISO14001, OHSAS18001, and BV certification. The slice does not provide certificate numbers, validity dates, or verification records, so the assessment is based on the supplier’s stated holdings.

After-Sales capabilityThe supplier reports clear procedures and followed records for corrective and preventive actions and customer complaints, plus quality assurance and material traceability. However, it has no overseas agents or branches, overseas warehouse, or showroom, which limits local service infrastructure.

R&D capabilityThe supplier reports R&D capability, new products in the past year, 3D software design services, and ODM services. It does not have an available SDK and does not provide OEM services for popular brands, but those limitations do not negate the stated product-development capabilities.

Production capacityEvidence includes valid contracts with every associated subcontractor, inventory capability, one-month average lead times in both peak and off-seasons, 20 qualified service-capability suppliers, standardized finished-product inspection instructions, and established production and testing structures. The supplier also reports 26 years of export experience and self-operated import/export rights.

Customization capabilityThe supplier explicitly offers customization from samples, customization from designs, full customization, minor customization, and flexible customization, together with 3D design and ODM services. This indicates broad design-to-production customization coverage.

Product Q&A

Q:Which kind of materials are available? Do they meet RoHS certification?

DoFo Spring is able to manufacture different spring types of compression springs, extension springs, torsion springs, wire forms with a large range of High-Grade Spring Steel - Carbon steel - Stainless steel - Music Wire, all comply to the RoHS standard. The wire diameter is available from 0.001 inches to 0.075 inches, which can meet the requirement of different applications. All the spring materials meet European RoHS certification.

Q:Do you support orders in small quantity or do you only accept large runs?

DoFo Spring manufactures large quantity springs, small quantity springs based on your demand. We will work with you to choose the most effective solution.

Q:Does DOFO spring offer DESIGN OR initial ASSISTANCE ON SPRINGS?

Our engineers could help with the design with the drawing and advise to lower the production cost. Our engineer has years of experience in spring design. We could provide drawing format in CAD, 3D, and 2D design layout as well as prototype development.

Q:What is the typical lead time for custom springs?

The lead time varies in custom springs. For compression springs, extension springs, torsion springs, wire forms in our mold range, we are able to deliver within 25 days. However, for some complex shapes of springs, the delivery time would be around 30~40 days.

Q:Do you charge custom spring samples?

We make the custom springs sample charge as a subscription of formal order. In other words, the sample charge could be refunded when we receive the order. However, if your sample requires an additional mold, we will charge it.