A smooth outer finish is always desirable for any surface or product to give out a sleek and shiny cover. Shot-blasting and sand-blasting have been among the top choices for any product manufacturer as both techniques get rid of outer debris and result in a fault-less polished surface.
We at Jay Ambay Etching Processes depend on the most economical methods and utilize the newly installed shot and sand-blasting machinery as suited for your products and their specifications to achieve unturned results in the end. Explore ahead how these techniques are different and which approach is ideal for your business.
Differences based on various industrial factors
The basic difference in the working mechanism
Shot-blasting is an airless blasting approach where the blast wheel utilizes internal centrifugal force and the wheel’s motion to shoot the material out onto the surface. A very few older models use the air blasting machines for shooting metal pellets. In contrast, sand-blasting uses either compressed liquid or air media as a propellant to force the abrasive material onto the product’s surface. By large, both techniques shoot material pellets onto the target surface to remove contaminating debris and polish it smoothly.
The material used for surface polishing
Shots in shot-blasting wheels are usually metallic, made of copper, aluminum, or steel grit, but those in sand-blasting machines are sand, aluminum oxide, silicon carbide, glass beads, and plastic pellets. The grit size or the dimension of the shooting pellets starts from 0.007 inches in diameter but largely depends on the mesh size of the machine used. Depending upon the surface put for refining and the contaminants required to eliminate, the apt size is chosen.
Surfaces the processes are applicable for
Sand-blasting is primarily applicable for cleaning purposes like removing the top layer of paint or rust from the product surfaces to prepare them for other works. Its low-pressure shooting effect works well on smooth surfaces like glass, minute electronic components, and wood without damaging or cracking them, which is a certain threat with shot-blasting.
Shot-blasting is thus applicable for scrapping rough surfaces, peening to pound mechanical stress for increasing durability and internal strength, or removing tightly-stuck debris from hard and dense surfaces like metals and concrete that can withstand the high pressure and velocity.
Both the techniques categorize themselves under the abrasive cleaning methods to remove the top layer of the surface, exposing a clean and fault-less layer from underneath. Sand-blasting machines are mostly small and hand-held by the workers to etch the surfaces directly by hand navigation.
On the other hand, shot blasters are bulky machines where the workers sit atop or push them using handles to polish the surface. The former method isn’t a closed environment, and the dust openly goes off into the air, but in the latter, the machine is compact and closes the surface it is acting on to reduce the dispersion to a great extent.
Time consumed and expense
Sand-blasting is relatively lengthier than shot-blasting as the machine works at low speed and effect, thus requiring multiple efforts to etch the surface smoothly. As the debris and dust are also dispersed, the process also includes an aftermath cleaning drive which isn’t that extensive for shot-blasting.
Along with the portable sandblasters, the workers also require compressors attached to their equipment for constantly producing pressurized gas or water. The expense also depends on the cost of the machinery, differing with the brand and features of various models. The abrasive media used in the process and the surface area covered also change the charges.
Say, steel grit pellets of shot-blasting are expensive compared to aluminum oxide, the best material for sand-blasting, which is quite cheaper and easy to obtain.
Safety of the workers
Sand-blasting often poses the threat of respiratory diseases like silicosis (lung cancer) among the workers since it uses fine sand and crystalline silica. The hand-held machines using highly compressed air also heat up quickly, which requires heavy protection and prior precaution to cover the entire body.
The high-quality shot-blasting machines are comparatively safe, as they suck the removed debris and also recycle the metal shots. The workers still need to cover themselves while working on-site as fine dust and removed toxic particles can still persist in the air. Compared to those in sand-blasting, the pellets in shot-blasting actually propel at a very high velocity, which can hit and injure like gun bullets if they aren’t confined and left to fly.
Noise pollution is a big concern in both of these abrasive techniques as the machines produce grinding noise unsuitable for long-term human exposure. Shot-blasting machines work in the range of 109-131dBA, whereas sand-blasting machines work in the range of 120-125dBA, which are practically very high levels.
Thus, full-face helmets are essential in both procedures to bring down the rumbling noise at least below 100dBA levels. Along with the noise, air pollution is also a major concern when surfaces are etched and cleaned. Sand-blasting definitely pollutes the air with its open exposure and use of sand and silica as shooting abrasives. In this case, shot-blasting is comparatively eco-friendly as it doesn’t pollute the environment much.
Where is shot-blasting usually preferred?
As it works effectively on hard surfaces, shot-blasting usually applies to industries working with metals. Aerospace, shipbuilding, railways, automobile manufacturers, industrial tool manufacturers, fabrications or casting, and forging industries employ this tough process.
They can eliminate minute internal defects, refine any metallic surface according to the industrial and market standards and finally make the products durable to resist practical obstructions. It is also an efficient job to clean concrete floors and pavements in constructional areas or vast complexes to cover a wide floor area in no time.
Where is sand-blasting usually preferred?
Since sand-blasting is primarily efficient for surface cleaning, it applies to every industry requiring a surface refurbishing job. Automobile industries use it for scraping paint and rust. Architects can clean walls to repaint or smooth the gritty surface to get fine sculptures. Delicate objects like semiconductors and micro-circuits in electronic industries or implants and equipment in the medical industries also require sand-blasting for careful cleaning.
Which one is a better approach?
Comparing the differences and applications of both the procedures, we can easily state that both have different functions and thus are applicable as deemed suitable. We, Jay Ambay Etching Processes, approach every customer with discreet examination to judge and execute the beneficial process apt for their requirement.
Sand-blasting is almost banned in many regions accounting for its health and environmental hazards that aren’t significant in the shot-blasting process. In general, soft and delicate surfaces requiring outer layer cleaning can opt for sand-blasting. However, shot-blasting is the best choice for performing refined tasks that involve mechanical changes or internal refining for hard surfaces.
Surface polishing techniques like sand-blasting and shot-blasting are abrasive approaches and similar in mechanical procedures to clean and refine the outer layer of any product or open surface. Both are vaguely different, involving varied equipment, work approach, and the environment they are apt to, making them fit for distinct tasks.
With efficient results and an appropriate approach to every product and material, Jay Ambay Etching Processes promises utmost care and guaranteed services with highly advanced and accurate sand-blasting and shot-blasting equipment to every approaching client.