Torque wrench. What is it? How to use it? How to set it correctly?
The correct torque is crucial for the proper assembly and operation of bolted connections in various structures and mechanisms. In such cases you cannot rely on feel alone; you must use appropriate tools that limit the maximum tightening force. Howeverhow do you set the correct Nm value on a torque wrench? And how do you calibrate a torque wrench? You can read about this in the article below
What is a torque wrench and how does it work?
To properly set a torque wrench, it is worth understanding how it works. The secret lies in a small spring. When the wrench encounters resistance, this spring stretches until the set torque (the Nm value on the scale) is reached — then a release of the lock occurs, preventing further tightening of the bolt. These tools belong toratchet wrenches, which means they transfer torque in only one direction (tightening bolts).
Analog or digital torque wrenches? Learn the different types
Among popular solutions, one can particularly mention:
Pointer (analog) torque wrenches. A classic solution equipped with a simple pointer and a graduated scale. This way you can monitor the correct tightening torqueof bolts during work. Some models additionally have a locking pawl that prevents tightening beyond the set torque.
Mechanical torque wrenches. The tool has a ratchet mechanism, so using a mechanical torque wrench is often associated with a characteristic click that indicates the set torque has been reached.
Electronic torque wrenches. They have an LCD screen showing the current torque. Electronic wrenches store presets, which significantly speeds up work, especially in auto workshops.
Break-type torque wrenches, which have an additional hinge. When the set torque is reached, the wrench 'breaks', preventing further operation. After removing it, it returns to the standard position, allowing further work.
Whether they are click wrenches, orprofessional torque wrenches with a scale, it is important to set the wrench correctly. How do you use it properly?
How to use a torque wrench?
A torque wrench is a delicateprecision tool. Therefore knowing why and how to use it is very important. A torque wrench is useful for tightening bolts during the assembly of many mechanical components, especially in automotive work or bicycles. Different types of wrencheshave different torque ranges, so they must be matched to the specific application. Proper storage of torque wrenches and regular calibration of the tools are also important. Correct wrench setting allows you to achieve the right tightening torque and will indicate the correct torque measurement.
What does Nm on a torque wrench mean and how important is torque?
The wrench's measurement range is very important. It is marked with a scale expressed in Nm. It representstightening torque values and stands for newton-meters. In other words it is the product of force (measured in newtons) and the lever arm at which it acts (in meters). By definition, one unit of torque means a force of 1 N acting on a lever arm (wrench length) of 1 m. The torque range depends on the mechanism used, i.e., the type of wrench.
Why should torque wrenches be used?
The user manual for many components specifies the need to use a torque wrench. Why is this so important? Sometimes there isa risk of damaging the connection if a bolt is overtightened. In other cases the bolt's structure may be compromised. In such a case the connection may fail at any time (e.g., during machine operation).Tightening wheel bolts should also be done with the correct torque so that the wheel does not come loose while driving. Precise tightening of bolts guarantees the proper functioning of the component.
How to set a torque wrench for wheels?
The tightening force for car wheel bolts is in the range of 110-140 Nm. Such a torque value secures the wheel against coming loose. Tightening wheel bolts should be done according to the vehicle's manual, because in some cases the recommended setting may fall outside the range mentioned above. It is also worth remembering that bicycle torque wrenches operate with much smaller torque.
Which torque wrench will fit an engine?
A wrench is also necessary when assembling an engine block. For this purpose a professional tool is used,whose torque measurement range is adjusted to that specific task. When assembling a block torque is important, but the correct sequence of tightening the individual bolts is equally crucial. Setting the torque wrench differs at various stages of engine assembly. It is often also necessary tocalibrate the torque wrench before starting work. The correct torque ensures the sealing of the entire assembly and trouble-free operation.Remember that the engine is not the only component in vehicles. Bolted connections occur, for example, in the running gear and in many other constructions, including those not related to cars.
Can you loosen bolts with a torque wrench?
Torque wrenches are intended for tightening bolts. As for loosening — do not do this, because it can lead to damage to the mechanism. Such damage to a torque wrench excludes further use of it. Indicated tightening torque values may become inaccurate. In most cases there is no possibility to calibrate a torque wrench.
Torque wrench: match the force to the application!
Properuse of an electronic wrench starts with choosing its power. Which wrench is needed for a given task depends on the job. That is why different types oftorque wrenches are available. How to choose them correctly?
Tightening car and motorcycle wheels requires quite a lot of force. Therefore in this case it is worth choosing a torque wrench with a range from 40 to 200 Nm.
To assemble an engine block, wrenches with a range up to 25 or 30 Nm are used.
The wrench's measurement range should be larger than the recommended setting, by at least several percent. Precise tightening is not possible near the ends of the scale, where the mechanism may show some deviations. Professional torque wrenches are designed for specific tasks so that recommended settings fall near the middle of the scale, providing the best accuracy of settings.
Which torque wrench will work well in a home garage?
Digital torque wrencheswork best in a home garage, providing the correct tightening torque. The torque setting is made using buttons and options visible on the screen, which makes the torque wrench easier to use for people who need them only occasionally. Memory presets also make it easier to reconfigure the device for repetitive tasks. For professional operators different types of tightening wrenches are recommended depending on the task, such as a torque wrench for engines. However, in a home garage a universal model with a wide adjustment range is often sufficient.How to calibrate a torque wrench?What is tool calibration and how does it work? It is a check to ensure that the tightening force corresponds to the reading. Using a torque wrenchrelies onthe correct tightening torque - therefore the measurement error cannot be too large. How to calibrate a torque wrench? The simplest way to calibrate is to send the wrench to a service. An alternative is to purchase a calibration device. This is a good solution for workshops that frequently use torque wrenches. Calibration should be performed at least once a year or after 5,000 uses.
Car warning vest should be in every vehicle – in case of a breakdown it will allow the driver standing next to the vehicle to remain visible even after dark. However high-visibility vests are also an essential piece of equipment for construction workers, road workers and many other jobs. Check what to consider when buying a warning vest!
Is a warning vest mandatory?
A warning vest is an inexpensive item of clothing that everyone should have. It is useful not only in the car, but also when cycling after dark or even as protection for a pedestrian walking on the roadside.
Do you have to have a warning vest in the car? Polish regulations do not impose such a requirement on drivers. They indicate, among other things, the need to have a reflective triangle and a fire extinguisher. Although you won't get a fine for not having a warning vest, it is definitely worth having one. If you often travel with passengers, it's best to equip yourself with reflective vests in quantities sufficient to provide visibility to passengers if needed.
Reflective warning vest – a requirement in many professions
While a high-visibility vest for a motorcycle, bicycle or car is not required by regulations, in some professions it is. Professional high-visibility clothing is a necessary part of the wardrobe for airport workers, heavy equipment operators, construction workers, and people performing official duties on roads or in railway areas.
As for warning vests, regulations in 2023 require them to be one of three colors: yellow, orange or red. In addition to fluorescent colors, they must also have reflective elements.
High-visibility clothing is divided into class one, two and three. In the case of warning vests only classes one and two are possible, because class three requires reflectors on the sleeves or trouser legs. Such a standard is met, for example, by warning jackets.
A class one high-visibility vest must have 0.14 m2 of fluorescent background, while the total area of reflective elements must be 0.10 m2. For class two these values are 0.50 m2 and 0.13 m2 respectively. A professional class 2 vest is ORLA Warning Vest. Available in two colors – orange and yellow, it meets EU standards EN ISO 20471 and EN ISO 13688. Two reflective strips 5 cm wide provide visibility, and the anatomical fit guarantees comfort of use of the reflective warning vest both during work duties and while traveling by bike, motorcycle or on foot.
Summer and winter warning vest to suit your needs
When choosing a reflective warning vest for pedestrians, cyclists or motorcyclists, pay particular attention to its size and the quality of the material. Contrary to appearances, fit is very important – especially if you will be wearing the vest for a long time. This type of body-protecting clothing is available in standard sizes – from S to 3XL. Importantly, these products are not divided into men's and women's high-visibility vests – they are universal garments with a simple cut.
In cold months, an insulated work warning vest will provide protection against cold, wind and precipitation. The REMS insulated warning vest model has a warm inner layer. An additional convenience is a zipper closure instead of traditional Velcro. This solution allows better protection against low temperatures and weather conditions. The REMS warning vest also has two inner pockets that allow for storing accessories useful at work.
How much does a reflective warning vest cost?
Purchasing a reflective PPE vest will not usually ruin the household budget of someone who wants to be visible while cycling or to have such important protection in the car.
You can also find much cheaper products in stores and at online auctions. Do yellow and orange reflective vests for 4–5 PLN differ from those from a trusted manufacturer costing a dozen or so zlotys? Although they may look the same at first glance, you will notice the difference in how long the product lasts. The reflective warning material on high-quality vests is much more durable – it retains its shape after many wash cycles. Meanwhile, cheap reflective vests often lose their properties after just 2–3 washes.
So if you don't want to spend two years wearing a vest that has never been washed, choose a higher-class product. Quality matters especially when you buy reflective warning PPE vests for your employees.
Of course you'll pay more for an insulated warning vest with pockets. For the aforementioned REMS model you'll pay 166 PLN. In this case, however, you should particularly take quality into account. A vest of poor quality, made of non-breathable material, will cause significant discomfort during work. It is definitely better to opt for products from a trusted warning vest manufacturer.Author: Paweł Sokołowski
WHAT IS THE CE MARK?
The CE marking (Conformité Européenne) is the European conformity mark. Its use on a product's packaging indicates that the manufacturer has applied and fulfilled the relevant requirements contained in European directives/regulations, as well as in the European standards covering the product. A product that meets safety requirements will be marked with the CE mark, thereby informing the user that it is safe and has been properly placed on the market.WHY WAS IT INTRODUCED?
After the European Union removed trade barriers between Member States and established a common policy toward partner countries outside the EU, an area of free movement of goods was created within the Community. However, the main barrier to trade remained national requirements concerning, for example, the quality and safety of products. The national systems of regulations and standards used by countries often differed significantly from one another. This caused a range of problems for manufacturers who, in order to sell their product in different countries, had to meet separate requirements each time.
Because consumer safety could not be compromised by eliminating standards, the only solution was to harmonize national systems so that goods would be subject to the same requirements throughout the Community.
In 1993, European legal acts called NEW APPROACH DIRECTIVES were created at EU level. They defined essential safety requirements for different groups of products that must be met before they can be placed on the market or put into service on the Single European Market.
IS CE MARKING MANDATORY OR VOLUNTARY?
if a product falls under one of the New Approach Directives, CE marking is mandatory.
applying CE marking to products that are not subject to the New Approach Directives is prohibited.
WHO CAN AFFIX THE CE MARK?
CE marking may be affixed by the manufacturer or their authorized representative. Most products fall under Module A, i.e., the manufacturer's self-assessment module. If another module applies (B or D), an EU type-examination certificate must be obtained in cooperation with a notified body (a certifying institute).
WHAT IS A CE CERTIFICATE?
The term "CE certificate" does not exist in the nomenclature of the New Approach directives. If someone talks about a CE certificate, they most likely mean the EU declaration of conformity or the EU type-examination certificate confirming the product's conformity with the relevant EN standard.
Currently, the process of marking and certification is regulated by Regulation (EU) 2016/425 of the European Parliament and of the Council of 9 March 2016 on personal protective equipment and repealing Council Directive 89/686/EEC.
Source: https://www.oznakowanie-ce.plAuthor: Grzegorz Nowak
In 2022 as many as 66,606 occupational accidents were reported in Poland. 365 of the injured suffered very serious injuries, and the number of fatal accidents amounted to 180. In almost 80% the lower or upper limbs were injured. Among the most common causes was contact with a stationary or moving object. These data clearly indicate how important it is to provide employees with appropriate protective clothing.
Differences between protective clothing and workwear
To begin with, it is worth dispelling an important mistake. The term „occupational protective clothing (PPE)” and “workwear” are often used interchangeably. However, they do not mean the same thing. To fully answer this question, it is useful to know the exact definitions of both concepts.
Definition of workwear and protective clothing
Workwear is clothing used in the workplace when there is a high risk of soiling or damaging outer garments. In other words, workwear replaces the employee’s clothing in situations where it may become dirty or ruined while performing duties. The use of uniform work outfits may also be related to building brand recognition (e.g., bank or insurance company employees).
And what is protective clothing? The definition states that it is clothing used in the workplace that is intended to cover or replace personal clothing. In addition, it is designed to provide protection against hazards. Both conditions must be met, so workwear that does not protect against specific dangerous substances or events is not protective clothing.
Applications of workwear and protective clothing
When is protective clothing used? Examples of such situations can be found in every industry. It is most often used by employees on production floors and those working in the field, and its purpose is to protect against impacts and cuts (such as protective boots with a steel toe cap). There is also protective clothing for welding and heavy aprons for laboratory technicians who come into contact with hazardous substances.
Work clothes are used even more frequently. They can be found in organizations that care about brand recognition linked to employee attire. Work uniforms are also widely used in the catering industry.
Types of protective and work clothing
Any clothing can be divided according to the part of the wardrobe it represents: protective or work gloves, trousers, jackets, boots or vests. It is worth paying more attention to the classification of protective clothing depending on the hazard it is meant to protect against. In this context, one can list:
Protective clothing for welders, protecting against electric arc, burns and splatter.
Harnesses related to working at heights.
Insulating protective clothing, used by electricians.
High-visibility clothing, protecting road workers, as well as emergency services operating at the scene of a road accident.
Chemical protective clothing, resistant to short-term exposure to hazardous corrosive substances.
Protective earmuffs that protect against excessively loud equipment noise.
Flame-resistant protective clothing for firefighters and people working near open flames.
Additionally, categories of protective clothing may also concern seasons, such as winter and summer protective clothing.
Protective clothing markings
Types of protective clothing can also be characterized by the areas of the body they are meant to protect.
Protective clothing (symbol U).
Lower limb protection (symbol N).
Upper limb protection (symbol R).
Head protection (symbol G).
Face and eye protection (symbol T).
Hearing protection (symbol S).
Respiratory protection (symbol D).
Protection against falls from height (symbol W).
Full body insulating protection (symbol I).
So how to choose the appropriate protective and work clothing for your workplace? That is always the employer’s responsibility!
Employer's obligations regarding protective and work clothing
Under current labor regulations, the employer is obliged to provide the employee free of charge with workwear, protective clothing and personal protective equipment (PPE) if required by the working conditions. Importantly, the decisive factor is the conditions prevailing in a given work environment, not, for example, the job title. For this reason, employees in similar positions at different companies may receive a different set of clothing.
Protective clothing is the employer's obligation
The employer must determine what professional workwear and protective clothing are needed for each employee. This usually takes place during a dialogue with employees or their representative. These arrangements are then entered into the work regulations, which define the conditions for being in the workplace, as well as equipping employees with tools, materials, protective and work clothing and personal and hygiene protective equipment. Typically the details are presented as a protective clothing allocation table for each position.
Work clothing and footwear provided by the employer
Work and protective clothing are provided free of charge. At the same time, they remain the property of the employer. This means that upon termination of employment, all personal protective equipment and allocated clothing must be returned to the supervisor. Also, in the event of clothing being destroyed due to the employee’s fault, reimbursement of the purchase costs is required (after accounting for depreciation).
Employer's duties regarding employee safety
The employer’s duties related to protective clothing and workwear also include cleaning, maintenance, repair, dust removal and disinfection. However, employees often wash their work clothes themselves. In such cases they are entitled to reimbursement of the costs they incur.
Standards and certifications of workwear and protective clothing
Workwear does not require certification, because its primary task is to protect personal clothing from dirt or damage. However, specialist protective clothing for workers must meet specific standards and criteria in order to effectively protect against hazards in the workplace.
Clothing materials: what determines their protective properties?
Protective garments are made from natural materials (cotton), regenerated (cellulose-based) and synthetic materials (polyester or polyamide). From these, several dozen popular materials with specific properties have been developed. Among them you can find:
Ortalion made from polyester. It is characterized by very low weight and high resistance to damage.
Fleece, a soft and warm polyester knit.
Stretch, i.e. stretch fabrics with added Lycra or PBT.
Corduroy, a warm cotton fabric resistant to cuts and tears, but prone to abrasion.
Ballistic nylon, also used in the production of bulletproof vests. It is very resistant to damage and abrasion.
Kevlar, an elastic material that is also extremely durable.
The choice of the appropriate material depends on the work environment and the conducted occupational risk analysis.
Certification by EN ISO standards: what does it mean for protective clothing?
In Poland, EU Regulation No. 2016/425 of 16 March currently applies. It specifies a number of standards for particular types of protective and specialized clothing. It is there that the exact parameters that protective clothing for firefighters, welders and other positions must meet are defined.
All protective garments must also have certificates confirming compliance with the above standards. To obtain them, clothing undergoes rigorous laboratory tests, which must then be repeated at regular intervals.
Summary: protective and work clothing
There are still many workplace accidents in Poland. To provide employees with the best possible protection, protective clothing and personal protective equipment are used in accordance with the protective clothing allocation table. Each such garment must meet protective clothing standards, confirming protection against hazards in the working environment.
In many positions, an employee also receives workwear that protects personal clothing from damage or soiling. In this case, there is no need to obtain certifications.
Both workwear and protective clothing belong to the employer, who should care for them: clean, repair and maintain them.Author: Grzegorz Nowak
