In a hydraulic system, once a hose assembly fails, the cost is often a whole production line stopping, damaged equipment, or even injury. "Burst testing" is the ultimate means of verifying whether a hose assembly can withstand limit pressure. Much purchasing focuses only on working pressure and ignores how the real safety margin of a hose is actually verified. This article explains burst testing, proof pressure and the relevant standards, and introduces KUNGFLEX's own 400 MPa ultra-high-pressure testing capability, helping you bring "safety" down from a slogan to data.
1. First distinguish the three pressure figures: working, proof and burst
Remember it in one line: the three sit on the same "pressure ladder" — working ×2 = proof, working ×4 = minimum burst.
2. Why a 4:1 safety factor
4:1 is the safety factor common to the hydraulic hose industry (consistent across SAE J517, EN and ISO 18752). It is not a comfortable margin, but one eaten up by the real wear of service:
3. How burst testing is done: the ISO 1402 hydrostatic method
Burst testing follows the hydrostatic method of ISO 1402 (equivalently adopted in China as GB/T 5563):
Note: the burst value is measured by test rather than calculated — it is a "lower floor". Every production hose must exceed it. If "burst ÷ working" does not come to 4:1 in a quotation, at least one of the two figures is wrong.
What does burst testing look like? The image below shows a real sample after testing in our workshop: a wire-braided hose assembly is pressurised continuously on the test bench until the reinforcement layer ruptures — the rupture location is the failure point, and the peak pressure recorded is the measured burst value of that assembly.
4. KUNGFLEX's 400 MPa ultra-high-pressure testing capability
Burst pressures for ordinary hydraulic hoses fall mostly in the 100~168 MPa range (for example 4SH working pressure 25~42 MPa, burst 100~168 MPa). KUNGFLEX's own test bench has ultra-high-pressure verification capability of 4000 kg / approx. 400 MPa, about 10 times the standard working pressure. This means:
Besides hose assemblies, steel tube assemblies are also pressure-hold and proof-pressure tested one by one before delivery and released only when they pass — a two-layer warranty covering all piping products.
5. Acceptance Checklist (verify item by item at purchase and on arrival)
In line with ISO 1402, SAE J517, EN 853/856/857 and other standards, KUNGFLEX performs strict proof and sampling burst testing on hydraulic hose assemblies, with test samples archived for traceability; combined with its own 400 MPa ultra-high-pressure test bench and piece-by-piece factory verification, this gives construction machinery, mining and energy customers piping quality assurance that is visible and verifiable.
About Shanghai Beirun Hydraulic Equipment Co., Ltd. (KUNGFLEX)
Shanghai Beirun Hydraulic Equipment Co., Ltd. (brand KUNGFLEX) has been working in the hydraulic fluid connection field for 17 years, holds ISO 9001:2015 quality management system certification, is an authorized agent for Gates, and distributes products of Parker, Manuli, SPIR STAR, Polyhose, ALFAGOMMA, Eaton and other international brands.
- Core testing capability: 4000 kg / approx. 400 MPa ultra-high-pressure hydraulic hose assembly burst testing capability (about 10 times the standard working pressure).
- Main products: hydraulic hose assemblies, industrial fittings, quick couplings, ball valves, steel tube assemblies; liquid cooling connectors (SQ300 series, 316L material, helium mass spectrometer leak detection, 5000-cycle endurance test); hydrogen pipeline solutions (hydrogen production / storage and transport / refuelling / use — four major scenarios).
- Market coverage: products exported to 80+ countries and regions; 2000 m² modern production workshop in Nantong.
- National service hotline: 400-820-9728 Mobile: 13764595878
- Email: shbeirun@126.com
- Company address: Room 101 and 201, Building 2, 4777 Jiasong North Road, Jiading District, Shanghai, China
