Drop Weight Tear Tester What is the drop-weight tear test? Steel pipelines are widely used to transport energy in the form of liquid petroleum and natural gas. The steel used in the manufacture of these pipelines must have high strength and toughness, and high resistance to fracture. Over the last few decades, it has become recognized that the drop-weight tear test (DWTT) better represents the ductile fracture resistance than the Charpy test since it utilizes a specimen that has the full thickness of the pipe and has a fracture path long enough to reach steadystate fracture resistance. The zones of ductile and brittle fracture during DWTT characterize the quality of pipeline steels. The drop weight tear test (DWTT), specified in API RP 5LR or ASTM E436, was developed in the early 1960s at the Battelle Memorial Institute, USA, to overcome some limitations of the 'Pellini' Drop-weight test. Drop weight tear testing is a material characterization test aimed at avoiding brittle fracture and ensuring crack arrest in pipelines (seamless or welded). Overview HUALONG WCJ Series is mainly used for drop weight tear test (DWTT) of Ferritic Steels, to observe specimen fracture surface after impact within the temperature that fracture type is converted from non-ductility to ductility. This test method is that hammer striker with some weights is raised to some height then released. Free drop hammer impacts and tears the specimen. After impact, proportions of ductile fracture (shear) and cleavage on the fracture surfaces are measured. Impactek data acquisition system is available to be introduced into DWTT tester, through which can upgrade simple uninstrumented DWTT tester to an instrumented DWTT tester who is able to measure the amount of force required to break a specimen, and this enables calculation of separate values for initiation energy and propagation energy, those impact resistance information gathered by doing instrumented testing can be used by Research and Development to evaluate the effects of metallurgical variables such as composition, processing, heat treatment can have on the fracture resistance of new or existing materials. Test results may also be used to indicate particular steel’s suitability for use in a specific application. Application range This testing machine accords with the relevant requirements of Standards for DWTT such as: Metallic materials－Drop-weight tear tests of ferritic steels. 1. API RP 5L3 2. ASTM E 436 3. EN 10274 4. GB 8363 The recommended practice API RP 5L3 issued by the American Petroleum Institute (API) describes the testing procedure to be used on large-drop impact testers. A specimen supported at both ends is impacted with a cold-press-fitted notch, with the point of impact opposite the notch. Since the specimen thicknesses are very large sections of actual pipeline tubes, high impact energies of up to 100,000 Joule are necessary to break the specimen. Main features 1. Regulating impact energy by adjusting the lifting height and mass of the weights. 2. Very robust construction stands up to the rigours of high energy testing to provide high reliability with a minimum of downtime

Drop Weight Tear Tester 3. The shock absorbers are equipped to absorb the residual energy after breaking the specimen to protect the weight and anvil from destroying. 4. Easily interchangeable contact parts simplify maintenance and reduce cost of ownership. 5. State-of-the-art testing accommodates impact energies up to 100,000J and specimens up to 50mm thick. 6. Automated specimen loading provides compliance with cycle times required by test methods, while maintaining operator safety. 7. Very rigid base and anvils ensures very low flexure under high test loads. 8. Guided mass system to ensure...

Drop Weight Tear Tester Hoist Mechanism Post Guide column Auto specimen feeding system (option) Drop weight Touch-screen Panel Console Safety cage with interlocks Temperature soak bath (option) Touch-screen Panel is for manual operation, commissioning as well as status observation

Drop Weight Tear Tester Maximum energy (J)

Drop Weight Tear Tester Drop Tower Four solid post ensure the high stiffness Two guide columns to ensure that the drop weight hit right in the center of specimen, chrome plated surface ensure the longest life as well as lowest friction Ladder to access top to facilitate installation and maintenance Enclosed by squared mesh panels secure the whole drop tower from top to bottom. Release cylinder Interlock cylinder Release of mass by rotation of hook on bottom of hoist mechanism, activation of both release cylinder and interlock cylinder required for release. Self-lubricating bearing Self-lubricating...

Drop Weight Tear Tester Shock absorbers, Anvil and Tup Shock absorber Specimen detector Note: Tup with load cell inside is for data acquisition option (instrumented DWTT) Winch Easy to access for periodic inspection and maintenance Servo Motor Fractured specimen conveyor AC brushless servo motor fitted with brake, driving sling via precision gearbox

Drop Weight Tear Tester Protective Cage Protective case secure the whole operation area

Drop Weight Tear Tester Temperature soak bath (option) External construction Internal construction Capacity Chamber access Temperature range Temperature accuracy (displayed versus actual) Temperature stability (at set-point) Cooling method Cooling medium Temperature sensor System control Temperature indication Protection Cooling medium consumption (estimated) Zinc-coated mild steel sheet. External surfaces finished in stoved epoxy paint. Bath and guides from 304 grade stainless steel. Sufficient to accommodate up to 10 (optional 12 pieces) specimens of thickness up to 50mm with minimum 26mm gap...

Drop Weight Tear Tester liquid Nitrogen-aided refrigeration option Liquid Nitrogen can significantly speed up the refrigeration. We are using the Liquid Nitrogen to cool down the cooling medium to certain temperature, then compressors continue cooling the cooling medium to the pre-set temperature, liquid Nitrogenaided refrigeration can significantly reduce the refrigeration time up to one hour.