About Longze Engineering
We take the engineering decision on fasteners and steel components — what the part has to be, written down against the published standard — and then deliver to it, verified.
Who we are
Longze Engineering is the export-facing brand of Hebei Longze Metal Products Manufacturing Co., LTD, a fastener manufacturer based in Handan, Hebei Province, China. We manufacture hex bolts, socket head cap screws, nuts and washers, and publish the underlying standard data — dimensions, materials, property classes and surface finishes — so that buyers can specify and verify every part.
How we work
We are not a parts catalogue. The job we take on is the engineering judgement — working out what a part has to be for the application, writing that down as a specification against the published standard, verifying that what arrives matches, and holding stock so it ships when you need it rather than when a production run allows.
Read how we work, step by step →
Related companies
Longze Engineering is the export brand of Hebei Longze Metal Products Manufacturing Co., Ltd. Two related companies share the same management and cover the rest of a project package: Hebei Zhongwulv Construction Engineering Co., Ltd takes on project contracting, and Hebei Shiwu Supply Chain Management Co., Ltd handles trade and supply chain services. Working together they are able to take on the material package for a project — steel and fasteners together — rather than only supplying loose parts.
Our history
| 2014 | Manufacturing operations at the Yongnian site began. The district, in Handan — China's principal fastener production base. |
|---|---|
| 2021 | The present legal entity, Hebei Longze Metal Products Manufacturing Co., Ltd, was registered (Unified Social Credit Code 91130408MA0G1UB924). |
| 2022 | Trademark 隆泽 (Longze) registered, Nice Class 6 (No. 55279729). |
| 2023 | Customs registration completed with Handan Customs (code 13049619HH), covering import and export in our own right. |
| 2024 | Certified to ISO 9001:2015, ISO 14001:2015 and ISO 45001:2018. Exhibited at the Hardware & Hand Tools fair in Vietnam and visited customer plants in the region. |
Today the company employs 45 people and operates 101 machines across forming, punching, welding and cutting.
Certifications
Our quality, environmental and occupational health & safety management systems are certified to ISO 9001:2015, ISO 14001:2015 and ISO 45001:2018. The certified scope covers the manufacturing and sales of fasteners, photovoltaic accessories, power rail accessories and embedded parts. We are also customs-registered for export.
See certificate numbers, validity dates and registrations →
What we supply
- Inch-series nuts to BSW and UNC — our core line, held in stock. UNC 1/4-20 through 3/4-10; BSW 1/4-20 through 1/2-12
- Metric fasteners — hex bolts, socket head cap screws, nuts and washers to DIN and ISO standards, M1.6 to M64
- Inch-series bolts, screws and washers — to ASME B18 series
- Packing, warehousing and call-off supply — packed to your requirement and released on your schedule
Stock, packing and logistics →
Ordering, quotation and delivery → · Quality checks, claims and after-sales →
Where we operate from
Our operations department is in Yongnian District, Handan City, Hebei — China's principal fastener production base. The surrounding supply base covers cold heading, thread rolling, heat treatment and surface finishing, which is what allows us to hold a wide specification range and verify every batch against the applicable standard before it ships.
International presence
We exhibit and meet buyers face to face rather than working only through directories. In late 2024 we exhibited at the Hardware & Hand Tools fair in Vietnam (stand A.A05) and visited customer plants in the region.
All exhibitions and industry activity →
Manufacturing capability
Our plant runs roll forming lines, presses up to 200 tons, welding robots, plasma and laser cutting — 101 machines in total. The same equipment serves both our fastener lines and our photovoltaic and power rail accessory production.
See the equipment list and production photos → · See reference projects →
Company details
| Legal entity | Hebei Longze Metal Products Manufacturing Co., LTD |
|---|---|
| Address | South of Xizhao Village, Linmingguan Town, Yongnian District, Handan City, Hebei Province, China |
| eric@lzfasteners.com | |
| Phone | +86-15350500528 |
| Business | OEM / ODM fastener manufacturing and export |
What we manufacture
- Hex bolts — DIN 931 (part thread), DIN 933 (full thread), ISO 4014, ISO 4017
- Socket head cap screws — DIN 912, ISO 4762, ASME B18.3
- Nuts — DIN 934, ISO 4032
- Washers — DIN 125-A, DIN 127-A, DIN 7980, ISO 7089
Size range and grades
Metric sizes from M1.6 to M64. Property classes 8.8, 10.9 and 12.9; stainless steel grades A2-70 and A4-80; washer hardness grades 100HV to 300HV.
Surface finishes
Zinc plating, hot-dip galvanizing (HDG), Dacromet, zinc flake and passivation. Coating thickness and salt-spray test data are published per standard so that finish selection can be made against a specification rather than a claim.
How we document standards
Every standard in our standards library is documented with its dimensional data, size matrix, material and finish options, and equivalence mapping to related DIN / ISO / ASME standards. Our engineering center covers equivalence clusters and specification detail.
Standards bodies
Our work references the published standards of the following bodies: DIN (Deutsches Institut fuer Normung), ISO (International Organization for Standardization), and ANSI / ASME B18 series.
Contact
For quotations, send the standard, size, property class, surface finish and quantity to eric@lzfasteners.com. We reply with FOB pricing and lead time.