How is a salt spray test chamber used to ensure durability

I. Salt spray test chamber|
Salt spray testing simulates a corrosive salty environment in the laboratory. It is used to speed the testing of surface coatings’ capacity to withstand air corrosion. It is one of the oldest testing procedures used in the HVAC-R coatings business and, as such, is frequently referred to when selecting HVAC-R coatings.

YWXQ-010 Salt Spray Test Chamber

II. Slat spray test chambers use
The salt spray test chamber is utilized in two ways for developing and testing HVAC-R and radiator coatings. Salt spray testing is utilized as a stand-alone corrosion resistance test as well as an ISO 12944-9 component (previously known as ISO 20340). The salt spray method is handled the same way for both tests, in accordance with ASTM B-117. To begin, tiny panels (usually 35 or 46 inches in length) are created with the coating to be evaluated. The edges and backs of the panels are often protected with tape. The panel is then “scribed” with a sharp tool to create a scratch through the coating to the metal substrate.

The prepared panel is then placed inside the test cabinet. Racks in the cabinet keep the panels in place as defined by ASTM B-117, angled back 15 to 30 degrees from vertical. The cabinet is then closed, and an atomizer delivers a 5% salt solution into it at a constant rate and temperature. Salt fog is blasted upwards, causing droplets to fall and settle on the panels.

Following this, the test panels will be checked on a regular basis, and the salt spray cabinet will be monitored to verify that it performs properly during the test. During these brief panel evaluations, it is established whether the test is continuing as planned or if the coating on the test panels is prematurely degrading. Although each laboratory is slightly different, the core test is as explained above.

There is a cabinet with a digital readout that displays the total hours of test cabinet operation, as well as alarms that will inform us about several vital things, such as if the salt solution level falls below a certain level. These characteristics are significant since some salt spray tests are exceedingly long. Some chambers have been tested for 6,000 hours or more against ASTM B-117. That is 250 days (or a bit more than 8 months) of continuous salt spray.

Although both ASTM B-117 and ISO 12944-9 are used to quantify corrosion protection, the two tests have major variances. In contrast to B-117, which is a static salt spray alone test, ISO 12944-9 is a cyclic test in which the panels are tested for 72 hours of UV exposure, 72 hours of salt spray, and 24 hours of freezing (for a total of 168 hours / one week). This cycle (UV / salt spray / freezing) is repeated for a total of 4,200 hours over a period of 25 weeks. Although neither test simulates a genuine outside environment, ISO 12944-9 closely resembles the harsh weather cycles that HVAC-R devices are frequently subjected to in the real world.

Considering this, the SSPC (The Society for Protective Coatings) concluded that “combined corrosion / weathering is a significant improvement to the traditional salt spray test (ASTM B117) in terms of speeding up the reproduction of atmospheric corrosion. Studies show that the ASTM-B117 salt spray test does not accurately reflect real-world environmental conditions. These studies help learn more about the differences between these two tests and why we assess against ISO 12944-9.

Once the required amount of exposure for ASTM B-117 or ISO 12944-9 has been attained, the lab will analyze the panel for degree of blistering, degree of rusting, and scribe creepage from the scribe. The outcomes are documented and shared on the Technical Data Sheets. These results are the basis for the test hours indicated on those Technical Data Sheets.

III. Installing and Configuring a Salt Spray Chamber
1)How to Unpack Your Salt Chamber
When opening the package, use caution. While the translucent sheeting commonly used in Lucite salt spray chambers is quite resilient, transportation can be rough enough to cause damage. Check your salt spray chamber for any cracks that may have developed during shipping. If you see a fracture or a chip in the Lucite, contact your manufacturer right away. A crack, like a vehicle windshield, can expand over time.Find a hard, level surface with plenty of airflow to serve as the salt spray chamber’s home. There should be enough of space surrounding the chamber in a well-ventilated area.

2)Requirements for Power and Utilities
The electric panels and chamber come fully wired and ready to use. Keep in mind that in most circumstances, the power supply must be grounded. You will also require a consistent supply of water. Notably, salt spray chambers necessitate the use of distilled (demineralized) water. Before using untreated tap water in your chamber, always run it via a demineralizer cartridge.
While the amount of water consumed by a chamber varies according on the type, here’s a formula to help determine the capacity of a

3)demineralizer cartridge
Capacity in gallons = 1600 grains TDS/17.12 ppm.
When three-quarters of the pellets have changed to their original color, that cartridge should be replaced.

IV. Assembly of the Salt Spray Nozzle
1)spray-nozzle
Salt spray chambers come with an atomizing nozzle, but if you need to replace it, you will probably need to do the following:
Tape all joints with a quarter-inch broad strip of Teflon tape. Avoid allowing the tape to enter the pipe. Tape should be applied at least two to three threads away from the pipe’s end. Screw the acrylic quarter-inch pipe nipple into the taped hole on the inside of the chamber while keeping any strange items out. You should be able to tighten it by hand with ease.

Tighten the nozzle by hand so that the spray is pointed toward the front of the chamber and the other taped hole in the nozzle points downward. Tighten the long acrylic quarter-inch threaded pipe until it fits snugly into the taped hole at the bottom of the nozzle. (This pipe is known as the syphon tube.) Place the nylon mesh strainer over the opposite end of the syphon tube and secure with rubber bands. Attach a specific MIL-STD-202 or MIL-STD-810 filter to the end of the syphon tube if one is utilized. Finish by placing the salt reservoir lid on top of the salt reservoir.

V. Ventilation of the Salt Spray Chamber
It must be emptied to prevent back pressure within the chamber. Install a non-corrosive three-quarter-inch pipe from the exhaust chamber to a place outside the building when constructing the chamber. To avoid liquid traps, this exhaust should be as short as possible, straight, and gently sloping downward from the chamber. It should also be protected from wind and air currents. While a flexible hose is an alternative, you must be careful that it does not droop in portions, causing liquid traps. A two-inch line should be utilized if the length of your exhaust exceeds 10 feet.

If your pipe must escape via the ceiling, utilize a T-fitting rather than an elbow. Align the T so that an 18-inch drop line and drain may be added to always keep the exhaust line free.

VI. Salt Spray Chamber Air Supply
A salt spray chamber requires clean, oil-free compressed air and has an “air” valve at the back end of the chamber. Compressed air flow SCFM typically ranges from 1.5/0.71 (liters/sec) to 4.0/1.89. Depending on the model, the PSIG pressure will range from 6 to 10.
Your salt spray chamber should now be fully operational. During operation, salt spray test chambers may maintain two highly exact temperatures, which is critical for consistent salt spray concentration and test item cover. The inside testing area is maintained at 35°C (95°F), while the external compartment is maintained at 45.5°C (113.9°F).

Working volume is defined as one-tenth of the length of each axis toward the test chamber’s center. These size-dependent minimum measurements define the volume within the test chamber exposed to high precision temperature uniformity. The temperature gradient and the temperature variance in space are the two averages that make up temperature uniformity. The average difference between the operational temperature in the middle of the test chamber and numerous different arbitrary places around the chamber is referred to as temperature variation in space.

The temperature gradient is the average difference in operating temperatures between the test chamber’s discretionary points. LISUN guarantees that your devices will be evaluated under consistent, dependable, and repeatable environmental circumstances.
Working volume is defined as one-tenth of the length of each axis toward the test chamber’s center. These size-dependent minimum measurements define the volume within the test chamber exposed to high precision temperature uniformity.

The temperature gradient and the temperature variance in space are the two averages that make up temperature uniformity. The average difference between the operational temperature in the middle of the test chamber and numerous different arbitrary places around the chamber is referred to as temperature variation in space. The temperature gradient is the average difference in operating temperatures between the test chamber’s discretionary points. LISUN guarantees that your devices will be evaluated under consistent, dependable, and repeatable environmental circumstances.

VII. Salt Spray Equipment
Salt spray test chambers include an atomizing nozzle for testing to the MIL-STD-19500B 40.8 specification. The atomizing nozzle ensures that the salt solution is introduced evenly and at the proper concentration into the test environment.

VIII. What to test with salt spray test chambers?
• Phosphate surfaces (with following paint/primer/lacquer/rust preventative)
• Plating with zinc and zinc alloys (see also electroplating)
• Chromium, nickel, copper, and tin electroplated
• Coatings that are not electrolytically applied (such as zinc flake coatings)
• Natural coatings
• Coatings for paint

VIIII. FAQs
1)What exactly is a salt spray testing chamber?
The Salt Spray Test Chamber is a piece of environmental testing equipment that evaluates the corrosion resistance of products or metal materials by recreating salt spray environmental conditions artificially.

2)What exactly is the purpose of a salt spray chamber?
Phosphate surfaces (with subsequent paint/primer/lacquer/rust preventative) Salt Spray chambers are often used to examine the corrosive qualities of: Plating with zinc and zinc alloys (see also electroplating) Chromium, nickel, copper, and tin electroplated.

3)How is a salt spray test evaluated?
Specimens are placed in a closed chamber and subjected to a dense metal fog that simulates highly corrosive conditions. The tests, which use a 5% sodium chloride solution with a pH between 6.5 and 7.2, can take anywhere from 8 to 3,000 hours (for exceptional circumstances).

Lisun Instruments Limited was found by LISUN GROUP in 2003. LISUN quality system has been strictly certified by ISO9001:2015. As a CIE Membership, LISUN products are designed based on CIE, IEC and other international or national standards. All products passed CE certificate and authenticated by the third party lab.

Our main products are Goniophotometer, Integrating Sphere, Spectroradiometer, Surge Generator, ESD Simulator Guns, EMI Receiver, EMC Test Equipment, Electrical Safety Tester, Environmental Chamber, Temperature Chamber, Climate Chamber, Thermal Chamber, Salt Spray Test, Dust Test Chamber, Waterproof Test, RoHS Test (EDXRF), Glow Wire Test and Needle Flame Test.

Please feel free to contact us if you need any support.
Tech Dep:  Service@Lisungroup.com , Cell/WhatsApp:+8615317907381
Sales Dep:  Sales@Lisungroup.com , Cell/WhatsApp:+8618117273997