1. Strapping Systems
2. Dunnage Air Bags
3. General
Actually, we have heard some rumours as well. But for all OEMSERV strapping and lashing belts, we can GUARANTEE that all figures stated on our documents will match with what we deliver. Our QC system is one of the most effective in the market. Surely mistakes can happen, but in OEMSERV there are very unlikely.
No, according to our self imposed QC rules only every 10th roll ( 10% ) of one shipment can have one ( 1 ) joint. That's very low.
The linear breaking strength (LBS) is tested in our laboratory and measured in daN. One belt is pulled in a special testing machine to its breaking point.
To calculate the system strength you can use this simple formula. The belt is used in a loop, so the system strength is double the LBS.
But there is a weak point in the system, the buckle. Modern standard buckles have a 'Joint Efficiency' of 80% on average.
So that lead to the following calculation: LBS x 2 x 0.8 f.e. LBS of 1000 daN provides a system strength of 1600 daN.
The result of this is the system strength, also called the breaking strength ( BS )
The maximum securing load ( MSL ) relates to the weight of the load. The IMO ( international maritime organisation ) recommends a safety factor of 2.
Meaning the belts of the strapping or lashing system should have the double breaking strength ( BS ) as the cargo weight to secure ( MSL ). ergo: MSL is always 50% of the BS
We do have a very view complains about delamination, overall less than 2%. Regardless of this small figure, we did investigate every single case.
As the result, we found that in almost all cases wrong buckles or a wrong tensioner has been used. Especially a cheap tensioner with a wrong breakle shoe can damage the Polyester Composite Strapping. We highly recommend using an OEMSERV tensioner since they are specially designed for all our products.
We suggest using our strap within one year since we do not know the weather and storage conditions.
Regarding the temperature range, we tested from -10 to +80 degrees Celsius.
In theory, there is no problem down to -30 degrees Celsius, but we never test so low since nobody uses the strap in such low temperatures.
For UV protection we add a UV stabilizer that does not mean the strap is resistant again to the UV but stable for a reasonable time.
We estimate it to be good for 7-10 Years. Since we can not be sure about all these figures we do not recommend the Polyester Composite Strapping
for outside construction. Besides all this, for sure the buckle can not last that long the metal will start to oxide after some time.
The advantages of using untwisted yarn are :
1) Strength of the yarn is up to 15 % higher
2) Price of the yarn is lower
3) elongation of the yarn is 5-10% lower, the elongation of the strap is also much lower.
Yes, our most common belts are AAR certified by our USA partner company.
The system strength for Polyester Composite Strap and the shock resistance is much higher.
According to our experiences, Polyester Composite Strap is not more expensive than steel or PET if you compare the system strength.
It is safer to use for the people in attach or detach the strap, it is safer in transport, it does not rust and it can be re-tensioned.
Worldwide wide we are replacing everyday steel strap with Polyester Composite Strap, so there is a very good chance.
Since steel strap is dangerous, harder to handle and less strong in the system.
No, we can not replace PET used in automatic machines. But we can offer a comprehensive range of high-quality PET strapping on request.
Yes, in some rare cases where buyers need to heat the goods after strapping here we can not use Composite strapping.
We compared composite Strap2000, metal strapping and PET strapping in the sizes of 13,16 and 19 mm.
It appeared that Polyester Composite Strapping has the best value of breaking strength in each size, metal strapping comes second.
The main advantage of Composite compare to PET is the edge Protection and much higher resistance against shock or mechanical stress on edges.
Besides this a PET system can reach 80 % System strength in lab conditions our minimum system strength is 80% usually we reach more than 85 %
Well, basically it depends on the application. While PP woven bags have many advantages, like cost efficiency, water prove or recycling matters, paper bags are stiffer. That makes them easier to apply in small gaps.
Yes, our medium standard 2ply paper bags are already certified, other models to follow.
Because this is very dangerous for those who open the container at arrival. The cargo might have shifted a little towards the doors and put enormous pressure on the bags. The doors can “explode” when opening and hurt people.
The average ( working ) pressure is around 0,05 bar. That is usually high enough to secure the cargo.
The max. filling pressure indicates how much the bag maximal can be filled. According to the international shipping safety regulations the burst pressure has to be 3 times higher than the maximum filling pressure for light and medium bags, and 2 times higher for heavy and super-heavy bags.
The most dominant figure for load securing with dunnage bags is the size of the gap between your cargo or the container wall.
Here is a simple data table to define a suitable airbag width.
< 30cm wide gap = 60cm wide bag
< 40cm wide gap = 90cm wide bag
< 50cm wide gap = 120cm wide bag
< 60cm wide gap = 150cm wide bag
The height of your airbag depends on the height of your cargo. It should be the same or a little shorter than the cargo.
The key to efficient safety is the contact surface of the airbag with the cargo. More contact, more safety and more weight can be secured.
The key to efficient safety is the contact surface of the airbag with the cargo. More contact, more safety and more weight can be secured.
And here is the formula:
A dunnage airbag filled with 1 bar pressure gives 10 N ( Newton ) per square centimetre of the contact surface.
Due to its physical construction, a dunnage bag changes its shape when inflated. While it has a 100% contact surface on both sides when flat, it decreases this percentage when filled, because it forms into a round shape.
f.e. a 90cm wide airbag has a contact surface of 80% in a 15cm wide gap. In a 30cm wide gap the contact surface is just 60% and in a 40cm wide gap only 40%. So, it is very important to use the right size in width to secure the cargo.
Securing Force = Contact surface ( f.e. airbag 90x180cm in 15cm gap filled with 0,2bar pressure ) 90*180*0,8*2*2 = 51840 Newton = 5184 daN = 5184 KG
Well, that is hard to say. As a manufacturer, we do not stock many items. Everything is freshly made when ordered. Since we offer a very wide range of load securing products, we have different production lines with different occupancy. Anyhow our target is to ship any order within 20 working days or less.
The overseas bank transaction charges of payment we receive from customers should be assumed by customers since it's stated on our Sales Contract:
"All banking charges outstanding in Hong Kong is for the account of the remitter."